infinite pill-shaped universe?

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Date: 09 Oct 2006 12:50:45
From: Liam
Subject: infinite pill-shaped universe?

Just found this CNN article where measured cosmic radioactivity seems
to indicate the universe is pill-shaped:
http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html

Now, I've just come to grips with the concept of the universe being
infinite and expanding out of a Big...Expanding like "raisin bread" or
an infinitely thick skin of a balloon.

Now this pill-shaped thing? I can't reconcile this in my mind.

Could someone help me understand how both of these can be true, or
whether one theory undermines the other?

Thanks!
Liam

Date: 09 Oct 2006 21:24:40
From: Double-A
Subject: Re: infinite pill-shaped universe?

honestjohn wrote:
> "Double-A" <double-aa@hush.ai> wrote in message
> news:1160437806.971802.241500@i42g2000cwa.googlegroups.com...
> >
> > Brian Tung wrote:
> > > Double-A wrote:
> > > > The universe cannot have both come out of the Big Bang and be
> infinite.
> > > > It has to be one or the other.
> > >
> > > It can be both with little trouble at all. Let's drop down a couple of
> > > dimensions, to make it easier to visualize.
> > >
> > > Suppose that there's a Big Bang that produces a circular universe. I
> > > don't mean a disc, with a circular edge; I mean a circle, so that all of
> > > the galaxies that make up this universe lie along the "edge," so to
> > > speak. If you run back time, you can easily see that the circle can
> > > shrink indefinitely, until it becomes a point right at the Big Bang.
> > >
> > > OK so far? Now, of course, such a universe isn't infinite; a circle has
> > > a well-defined and finite length. So what I'm going to do is to replace
> > > that circle by an infinite slinky. It's now that infinite slinky that
> > > we run backward into time, so that it becomes a point right at the Big
> > > Bang.
> > >
> > > Impossible, you say? The only things that stop us are that there are no
> > > infinite slinkies, and that slinkies have depth; they're not perfectly
> > > flat. But neither of these things are problems in *principle*. We can
> > > imagine an infinitely long slinky, even if we can't produce one in
> > > actuality. And in principle, if a slinky is truly one-dimensional, it
> > > has no thickness at all. That means that you can coil one up as long as
> > > you like--infinitely long, even--and it will never gain any depth. It
> > > will look just like a circle, except that it's not actually closed; if
> > > you move along the slinky universe, you never get back to your starting
> > > point unless you turn back and go the other way.
> > >
> > > Pump things up a couple of dimensions, and you have a universe that can
> > > expand out of a Big Bang and be infinite the whole time. (Actually,
> > > "flatten out" is probably a more accurate term than "expand out.")
> > >
> > > --
> > > Brian Tung <brian@isi.edu>
> > > The Astronomy Corner at http://astro.isi.edu/
> > > Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
> > > The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
> > > My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
> >
> >
> > If you want to invoke extra dimensions, I would agree with you.
> >
> > But as a three-dimensional construct, a universe that expanded out of a
> > finite size, must still be finite. Fact is, in spite of years of
> > endless speculation about extra dimensions none has yet been observed
> > or detected.
> >
> > Double-A
> >
> Mathematics of Physics only works out correctly when 11 dimensions are used.
> Go figure.
>
> C.H.J.

That's String Theory, another flight of fanciful speculation still
looking for any supporting evidence in the real world.

Double-A

Date: 09 Oct 2006 16:50:07
From: Double-A
Subject: Re: infinite pill-shaped universe?

Brian Tung wrote:
> Double-A wrote:
> > The universe cannot have both come out of the Big Bang and be infinite.
> > It has to be one or the other.
>
> It can be both with little trouble at all. Let's drop down a couple of
> dimensions, to make it easier to visualize.
>
> Suppose that there's a Big Bang that produces a circular universe. I
> don't mean a disc, with a circular edge; I mean a circle, so that all of
> the galaxies that make up this universe lie along the "edge," so to
> speak. If you run back time, you can easily see that the circle can
> shrink indefinitely, until it becomes a point right at the Big Bang.
>
> OK so far? Now, of course, such a universe isn't infinite; a circle has
> a well-defined and finite length. So what I'm going to do is to replace
> that circle by an infinite slinky. It's now that infinite slinky that
> we run backward into time, so that it becomes a point right at the Big
> Bang.
>
> Impossible, you say? The only things that stop us are that there are no
> infinite slinkies, and that slinkies have depth; they're not perfectly
> flat. But neither of these things are problems in *principle*. We can
> imagine an infinitely long slinky, even if we can't produce one in
> actuality. And in principle, if a slinky is truly one-dimensional, it
> has no thickness at all. That means that you can coil one up as long as
> you like--infinitely long, even--and it will never gain any depth. It
> will look just like a circle, except that it's not actually closed; if
> you move along the slinky universe, you never get back to your starting
> point unless you turn back and go the other way.
>
> Pump things up a couple of dimensions, and you have a universe that can
> expand out of a Big Bang and be infinite the whole time. (Actually,
> "flatten out" is probably a more accurate term than "expand out.")
>
> --
> Brian Tung <brian@isi.edu>
> The Astronomy Corner at http://astro.isi.edu/
> Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
> The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
> My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

If you want to invoke extra dimensions, I would agree with you.

But as a three-dimensional construct, a universe that expanded out of a
finite size, must still be finite. Fact is, in spite of years of
endless speculation about extra dimensions none has yet been observed
or detected.

Double-A

Date: 10 Oct 2006 04:41:52
From: Chris L Peterson
Subject: Re: infinite pill-shaped universe?

On 9 2006 16:50:07 -0700, "Double-A" <double-aa@hush.ai > wrote:

>If you want to invoke extra dimensions, I would agree with you.
>
>But as a three-dimensional construct, a universe that expanded out of a
>finite size, must still be finite. Fact is, in spite of years of
>endless speculation about extra dimensions none has yet been observed
>or detected.

Not so. There are many different sorts of independent observation that
support the idea that we live in at least a four dimensional universe.
If the Universe as we see it were a simple three dimensional structure
it would be at odds with what we observe.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Date: 09 Oct 2006 22:24:13
From: honestjohn
Subject: Re: infinite pill-shaped universe?

"Double-A" <double-aa@hush.ai > wrote in message
news:1160437806.971802.241500@i42g2000cwa.googlegroups.com...
>
> Brian Tung wrote:
> > Double-A wrote:
> > > The universe cannot have both come out of the Big Bang and be
infinite.
> > > It has to be one or the other.
> >
> > It can be both with little trouble at all. Let's drop down a couple of
> > dimensions, to make it easier to visualize.
> >
> > Suppose that there's a Big Bang that produces a circular universe. I
> > don't mean a disc, with a circular edge; I mean a circle, so that all of
> > the galaxies that make up this universe lie along the "edge," so to
> > speak. If you run back time, you can easily see that the circle can
> > shrink indefinitely, until it becomes a point right at the Big Bang.
> >
> > OK so far? Now, of course, such a universe isn't infinite; a circle has
> > a well-defined and finite length. So what I'm going to do is to replace
> > that circle by an infinite slinky. It's now that infinite slinky that
> > we run backward into time, so that it becomes a point right at the Big
> > Bang.
> >
> > Impossible, you say? The only things that stop us are that there are no
> > infinite slinkies, and that slinkies have depth; they're not perfectly
> > flat. But neither of these things are problems in *principle*. We can
> > imagine an infinitely long slinky, even if we can't produce one in
> > actuality. And in principle, if a slinky is truly one-dimensional, it
> > has no thickness at all. That means that you can coil one up as long as
> > you like--infinitely long, even--and it will never gain any depth. It
> > will look just like a circle, except that it's not actually closed; if
> > you move along the slinky universe, you never get back to your starting
> > point unless you turn back and go the other way.
> >
> > Pump things up a couple of dimensions, and you have a universe that can
> > expand out of a Big Bang and be infinite the whole time. (Actually,
> > "flatten out" is probably a more accurate term than "expand out.")
> >
> > --
> > Brian Tung <brian@isi.edu>
> > The Astronomy Corner at http://astro.isi.edu/
> > Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
> > The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
> > My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
>
>
> If you want to invoke extra dimensions, I would agree with you.
>
> But as a three-dimensional construct, a universe that expanded out of a
> finite size, must still be finite. Fact is, in spite of years of
> endless speculation about extra dimensions none has yet been observed
> or detected.
>
> Double-A
>
Mathematics of Physics only works out correctly when 11 dimensions are used.
Go figure.

C.H.J.

Date: 09 Oct 2006 15:18:50
From: Double-A
Subject: Re: infinite pill-shaped universe?

Dana wrote:
> "Double-A" <double-aa@hush.ai> wrote in message
> news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
> >
> > Liam wrote:
> > > Just found this CNN article where measured cosmic radioactivity seems
> > > to indicate the universe is pill-shaped:
> > > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> > >
> > > Now, I've just come to grips with the concept of the universe being
> > > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > > an infinitely thick skin of a balloon.
> >
> >
> > The universe cannot have both come out of the Big Bang and be infinite.
> > It has to be one or the other.
>
> Why do you say this.

Was the universe infinite at one second after the Big Bang?

Double-A

Date: 09 Oct 2006 14:40:37
From: Dana
Subject: Re: infinite pill-shaped universe?

"Double-A" <double-aa@hush.ai > wrote in message
news:1160432330.054745.200620@i3g2000cwc.googlegroups.com...
>
> Dana wrote:
> > "Double-A" <double-aa@hush.ai> wrote in message
> > news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
> > >
> > > Liam wrote:
> > > > Just found this CNN article where measured cosmic radioactivity
seems
> > > > to indicate the universe is pill-shaped:
> > > > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> > > >
> > > > Now, I've just come to grips with the concept of the universe being
> > > > infinite and expanding out of a Big...Expanding like "raisin bread"
or
> > > > an infinitely thick skin of a balloon.
> > >
> > >
> > > The universe cannot have both come out of the Big Bang and be
infinite.
> > > It has to be one or the other.
> >
> > Why do you say this.
>
> Was the universe infinite at one second after the Big Bang?

OK, good point.

>
> Double-A
>

Date: 13 Oct 2006 14:20:02
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"Dana" <raff242@yahoo.com > wrote in message
news:12iljt4nbg3cd@corp.supernews.com...
>
> "Double-A" <double-aa@hush.ai> wrote in message
> news:1160432330.054745.200620@i3g2000cwc.googlegroups.com...
>>
>> Dana wrote:
>> > "Double-A" <double-aa@hush.ai> wrote in message
>> > news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
...
>> > > The universe cannot have both come out of the Big Bang and be
>> > > infinite.
>> > > It has to be one or the other.
>> >
>> > Why do you say this.
>>
>> Was the universe infinite at one second after the Big Bang?
>
> OK, good point.

I don't know why you say that, the equations say it
was infinite at _all_ times if it is infinite now.
That is, it was never anything other than infinite.

"Double-A" seems to be making the common mistake of
thinking of the initial event as an explosion in
pre-existing space.

George

Date: 13 Oct 2006 08:47:04
From: richard schumacher
Subject: Re: infinite pill-shaped universe?

The universe is shaped like Brad Guth?

Date: 13 Oct 2006 22:32:23
From: Peter Webb
Subject: Re: infinite pill-shaped universe?

"Dana" <raff242@yahoo.com > wrote in message
news:12iljt4nbg3cd@corp.supernews.com...
>
> "Double-A" <double-aa@hush.ai> wrote in message
> news:1160432330.054745.200620@i3g2000cwc.googlegroups.com...
>>
>> Dana wrote:
>> > "Double-A" <double-aa@hush.ai> wrote in message
>> > news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
>> > >
>> > > Liam wrote:
>> > > > Just found this CNN article where measured cosmic radioactivity
> seems
>> > > > to indicate the universe is pill-shaped:
>> > > > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>> > > >
>> > > > Now, I've just come to grips with the concept of the universe being
>> > > > infinite and expanding out of a Big...Expanding like "raisin bread"
> or
>> > > > an infinitely thick skin of a balloon.
>> > >
>> > >
>> > > The universe cannot have both come out of the Big Bang and be
> infinite.
>> > > It has to be one or the other.
>> >
>> > Why do you say this.
>>
>> Was the universe infinite at one second after the Big Bang?
>
> OK, good point.
>
>>
>> Double-A
>>
>
>

No, crap point.

It may take any positive age, and hence be potentially infinite in the
forward direction.

Date: 09 Oct 2006 22:04:04
From: Sorcerer
Subject: Re: infinite pill-shaped universe?

"Liam" <news@celticbear.com > wrote in message
news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...

Date: 09 Oct 2006 20:46:18
From: stapleton
Subject: Re: infinite pill-shaped universe?

I think you can not say the universe is shaped like a pill.
A bit like thinking that peeled orange map of the world
is a true representation of the earth.

No doubt the "pill" shape is a compromised 3-D representation.

"Liam" <news@celticbear.com > wrote in message
news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
> Just found this CNN article where measured cosmic radioactivity seems
> to indicate the universe is pill-shaped:
> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
> Now, I've just come to grips with the concept of the universe being
> infinite and expanding out of a Big...Expanding like "raisin bread" or
> an infinitely thick skin of a balloon.
>
> Now this pill-shaped thing? I can't reconcile this in my mind.
>
> Could someone help me understand how both of these can be true, or
> whether one theory undermines the other?
>
> Thanks!
> Liam
>

Date: 09 Oct 2006 20:40:06
From: Sam Wormley
Subject: Re: infinite pill-shaped universe?

Liam wrote:
> Just found this CNN article where measured cosmic radioactivity seems
> to indicate the universe is pill-shaped:
> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>

Egg-shaped Universe? Probably Not
http://www.astro.ucla.edu/~wright/cosmolog.htm#News

"30 Sep 2006 - The Los Angeles Times has a story today about the
paper* that suggests the Universe might be egg-shaped, and that
this might explain the low quadrupole seen in the WMAP (and COBE
DMR) CMB anisotropy maps. This was a silly paper and I said as
much to the reporter John Johnson. Adding an additional
quadrupole from the ellipsoidal Universe will make the
probability of the low observed quadrupole even smaller, unless
there is a reason that the quadrupole from the ellipticity will
be equal and nearly opposite to the quadrupole from inflation.
No such reason is given in this paper. Unfortunately the
referees for the Physical Review Letters missed this, and the
American Institute of Physics issued a press release
(subscription) about the paper".

*http://arxiv.org/abs/astro-ph/0606266

Date: 09 Oct 2006 13:36:06
From: Double-A
Subject: Re: infinite pill-shaped universe?

CptDondo wrote:
> Double-A wrote:
> >
> > The universe cannot have both come out of the Big Bang and be infinite.
> > It has to be one or the other.
>
> Sure it can. You can have a shape with an infinite volume but a finite
> boundary, and vice-versa.

Sounds like a black hole.

Double-A

Date: 09 Oct 2006 20:36:09
From: Algomeysa2
Subject: Re: infinite pill-shaped universe?

Date: 10 Oct 2006 18:28:50
From: jacob navia
Subject: Re: infinite pill-shaped universe?

Algomeysa2 wrote:
> "Liam" <news@celticbear.com> wrote in message
> news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
>
>>Just found this CNN article where measured cosmic radioactivity seems
>>to indicate the universe is pill-shaped:
>>http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
>
> Well, back in 2003 the universe was shaped like a soccer ball:
>
> http://news.nationalgeographic.com/news/2003/10/1008_031008_finiteuniverse.html
>
> Now it's shaped like a pill.
>
> I would suggest that the universe will continue to change shape as long as
> scientists need to publish papers....
>
>

!!!!!!!

VERY WELL WRITTEN.

Exactly. All this talk about the "shape of the universe" is just NONSENSE!

Date: 12 Oct 2006 02:48:43
From: Ben Rudiak-Gould
Subject: Re: infinite pill-shaped universe?

Algomeysa2 wrote:
> Well, back in 2003 the universe was shaped like a soccer ball:
>
> http://news.nationalgeographic.com/news/2003/10/1008_031008_finiteuniverse.html
>
> Now it's shaped like a pill.

No astronomer ever claimed it had either of those shapes. Only clueless
reporters did. Furthermore, neither of these claims (the real claims, not
the misreported ones) ever had wide support. Scientists publish conjectures
all the time. Most of them don't pan out. That's not a bad thing. What is a
bad thing is newspapers randomly reporting on speculative papers as though
they were accepted wisdom. It gives people a terribly distorted view of the
scientific process, even if the reporting is accurate, which it never is.

-- Ben

Date: 09 Oct 2006 13:35:10
From: Liam
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
> Liam wrote:
> > Just found this CNN article where measured cosmic radioactivity seems
> > to indicate the universe is pill-shaped:
> > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> >
> > Now, I've just come to grips with the concept of the universe being
> > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > an infinitely thick skin of a balloon.
>
>
> The universe cannot have both come out of the Big Bang and be infinite.
> It has to be one or the other.
>

Well, as I understand it, "The Big Bang" is a huge misnomer (and is a
term not even created by scientists.)
http://www.astro.ucla.edu/~wright/nocenter.html
http://www.astro.ucla.edu/~wright/cosmology_faq.html
Evidently the commonly accepted theory is the infinite universe
basically expanded out as every point is the center, and every point
was the origin of a Big Expansion. Like an infinitely thick expanding
balloon skin and or rising raisin bread.

>
> > Now this pill-shaped thing? I can't reconcile this in my mind.
> >
> > Could someone help me understand how both of these can be true, or
> > whether one theory undermines the other?
> >
> > Thanks!
> > Liam
>
>
> "An ellipsoid universe could be caused by a magnetic field pervading
> the cosmos that stretches space-time, he said, or by space-time defects
> such as cosmic strings, immensely dense structures just a proton or so
> wide stretched to intergalactic scales, whose gravity could distort
> space and time."
>
>
> Did anyone consider spin?
>
> Double-A

Date: 11 Oct 2006 18:55:36
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"Liam" <news@celticbear.com > wrote in message
news:1160426110.719469.232780@m7g2000cwm.googlegroups.com...
>
> Double-A wrote:
>> Liam wrote:
>> > Just found this CNN article where measured cosmic radioactivity seems
>> > to indicate the universe is pill-shaped:
>> > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>> >
>> > Now, I've just come to grips with the concept of the universe being
>> > infinite and expanding out of a Big...Expanding like "raisin bread" or
>> > an infinitely thick skin of a balloon.
>>
>>
>> The universe cannot have both come out of the Big Bang and be infinite.
>> It has to be one or the other.
>>
>
> Well, as I understand it, "The Big Bang" is a huge misnomer (and is a
> term not even created by scientists.)
> http://www.astro.ucla.edu/~wright/nocenter.html
> http://www.astro.ucla.edu/~wright/cosmology_faq.html
> Evidently the commonly accepted theory is the infinite universe
> basically expanded out as every point is the center, and every point
> was the origin of a Big Expansion. Like an infinitely thick expanding
> balloon skin and or rising raisin bread.

That is a good description of the current view.

>> > Now this pill-shaped thing? I can't reconcile this in my mind.
>> >
>> > Could someone help me understand how both of these can be true, or
>> > whether one theory undermines the other?

The whole universe may well be infinite. Think of
yourself on a plane in the middle of an infinite
cloud. Suppose the visibility is 100 yards. The
surface you can see should be a sphere centred on
you with that radius. They are suggesting we can
see a little farther in the horizontal directions
than in the vertical so the shape would be a
rotated ellipse.

Does that help?

George

Date: 09 Oct 2006 13:27:03
From: Double-A
Subject: Re: infinite pill-shaped universe?

Date: 09 Oct 2006 15:49:09
From: Brian Tung
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
> The universe cannot have both come out of the Big Bang and be infinite.
> It has to be one or the other.

It can be both with little trouble at all. Let's drop down a couple of
dimensions, to make it easier to visualize.

Suppose that there's a Big Bang that produces a circular universe. I
don't mean a disc, with a circular edge; I mean a circle, so that all of
the galaxies that make up this universe lie along the "edge," so to
speak. If you run back time, you can easily see that the circle can
shrink indefinitely, until it becomes a point right at the Big Bang.

OK so far? Now, of course, such a universe isn't infinite; a circle has
a well-defined and finite length. So what I'm going to do is to replace
that circle by an infinite slinky. It's now that infinite slinky that
we run backward into time, so that it becomes a point right at the Big
Bang.

Impossible, you say? The only things that stop us are that there are no
infinite slinkies, and that slinkies have depth; they're not perfectly
flat. But neither of these things are problems in *principle*. We can
imagine an infinitely long slinky, even if we can't produce one in
actuality. And in principle, if a slinky is truly one-dimensional, it
has no thickness at all. That means that you can coil one up as long as
you like--infinitely long, even--and it will never gain any depth. It
will look just like a circle, except that it's not actually closed; if
you move along the slinky universe, you never get back to your starting
point unless you turn back and go the other way.

Pump things up a couple of dimensions, and you have a universe that can
expand out of a Big Bang and be infinite the whole time. (Actually,
"flatten out" is probably a more accurate term than "expand out.")

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 09 Oct 2006 13:33:28
From: Dana
Subject: Re: infinite pill-shaped universe?

"Double-A" <double-aa@hush.ai > wrote in message
news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
>
> Liam wrote:
> > Just found this CNN article where measured cosmic radioactivity seems
> > to indicate the universe is pill-shaped:
> > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> >
> > Now, I've just come to grips with the concept of the universe being
> > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > an infinitely thick skin of a balloon.
>
>
> The universe cannot have both come out of the Big Bang and be infinite.
> It has to be one or the other.

Why do you say this.

Date: 09 Oct 2006 20:49:09
From: stapleton
Subject: Re: infinite pill-shaped universe?

"Double-A" <double-aa@hush.ai > wrote in message
news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
>
> Liam wrote:
>> Just found this CNN article where measured cosmic radioactivity seems
>> to indicate the universe is pill-shaped:
>> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>
>> Now, I've just come to grips with the concept of the universe being
>> infinite and expanding out of a Big...Expanding like "raisin bread" or
>> an infinitely thick skin of a balloon.
>
>
> The universe cannot have both come out of the Big Bang and be infinite.
> It has to be one or the other.

I think its beyond our ability to understand in human terms.
Time and space do not exist outside of the "expanding universe".

Date: 10 Oct 2006 18:27:19
From: jacob navia
Subject: Re: infinite pill-shaped universe?

stapleton wrote:
>
> I think its beyond our ability to understand in human terms.
> Time and space do not exist outside of the "expanding universe".
>
>

Excuse me but if "its beyond our ability to understand in human terms"
then it is NOT SCIENCE but religion.

Date: 11 Oct 2006 01:19:47
From: stapleton
Subject: Re: infinite pill-shaped universe?

"jacob navia" <jacob@jacob.remcomp.fr > wrote in message
news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
> stapleton wrote:
>>
>> I think its beyond our ability to understand in human terms.
>> Time and space do not exist outside of the "expanding universe".
>
> Excuse me but if "its beyond our ability to understand in human terms"
> then it is NOT SCIENCE but religion.

There are ALOT of things in science that are not understandable in human
terms.
Take a class in quantum mechanics. You see crazy formulas like:
time * space = mass * energy * Si (Si is a constant)

There are even more thinks in science that are hard to comprehend.

Such as general relativity theory.
As an object approaches the speed of light, its mass becomes infinite and
time slows.

Just trying to imagine the mass of a teaspoon of matter form a black hole
is impossible to imagine. It would be so heavy it would sink to the center
of the earth, keep going, and rebounce multiple times before coming to rest
at the center.

Or Nuetrinos. They pass through the earth as if the earth were thin air.

etc ....

Date: 10 Oct 2006 20:59:50
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear stapleton:

"stapleton" <alier342@silverman.com > wrote in message
news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
>
> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
>> stapleton wrote:
>>>
>>> I think its beyond our ability to understand in human
>>> terms. Time and space do not exist outside of the
>>> "expanding universe".
>>
>> Excuse me but if "its beyond our ability to understand
>> in human terms" then it is NOT SCIENCE but religion.
>
> There are ALOT of things in science that are not
> understandable in human terms.
> Take a class in quantum mechanics. You see crazy
> formulas like: time * space = mass * energy * Si
> (Si is a constant)
>
> There are even more thinks in science that are hard to
> comprehend.
>
> Such as general relativity theory.
> As an object approaches the speed of light, its mass

... *energy*, not mass ...

> becomes infinite and time slows.
>
> Just trying to imagine the mass of a teaspoon of matter
> form a black hole is impossible to imagine. It would be
> so heavy it would sink to the center of the earth, keep
> going, and rebounce multiple times before coming to rest
> at the center.

... or even explode out into a whole new Universe.

> Or Nuetrinos. They pass through the earth as if the
> earth were thin air.
>
> etc ....

Good points all.

David A. Smith

Date: 11 Oct 2006 13:36:32
From: stapleton
Subject: Re: infinite pill-shaped universe?

"N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com > wrote in
message news:O_ZWg.3210$v43.2775@fed1read02...
> Dear stapleton:
>
> "stapleton" <alier342@silverman.com> wrote in message
> news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
>>
>> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
>> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
>>> stapleton wrote:
>>>>
>>>> I think its beyond our ability to understand in human
>>>> terms. Time and space do not exist outside of the
>>>> "expanding universe".
>>>
>>> Excuse me but if "its beyond our ability to understand
>>> in human terms" then it is NOT SCIENCE but religion.
>>
>> There are ALOT of things in science that are not
>> understandable in human terms.
>> Take a class in quantum mechanics. You see crazy
>> formulas like: time * space = mass * energy * Si
>> (Si is a constant)
>>
>> There are even more thinks in science that are hard to
>> comprehend.
>>
>> Such as general relativity theory.
>> As an object approaches the speed of light, its mass
>
> ... *energy*, not mass ...

http://einstein.stanford.edu/content/relativity/q389.html
Experimentally, the increase of mass with velocity has been confirmed to
great precision...

Date: 11 Oct 2006 18:47:55
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"stapleton" <alier342@silverman.com > wrote in message
news:Ar6Xg.21729$Ij.5438@newssvr14.news.prodigy.com...
>
> "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com> wrote in
> message news:O_ZWg.3210$v43.2775@fed1read02...
>> Dear stapleton:
>>
>> "stapleton" <alier342@silverman.com> wrote in message
>> news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
>>>
>>> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
>>> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
>>>> stapleton wrote:
>>>>>
>>>>> I think its beyond our ability to understand in human
>>>>> terms. Time and space do not exist outside of the
>>>>> "expanding universe".
>>>>
>>>> Excuse me but if "its beyond our ability to understand
>>>> in human terms" then it is NOT SCIENCE but religion.
>>>
>>> There are ALOT of things in science that are not
>>> understandable in human terms.
>>> Take a class in quantum mechanics. You see crazy
>>> formulas like: time * space = mass * energy * Si
>>> (Si is a constant)
>>>
>>> There are even more thinks in science that are hard to
>>> comprehend.
>>>
>>> Such as general relativity theory.
>>> As an object approaches the speed of light, its mass
>>
>> ... *energy*, not mass ...
>
> http://einstein.stanford.edu/content/relativity/q389.html
> Experimentally, the increase of mass with velocity has been confirmed to
> great precision...

The FAQ:

http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html

Scientifically speaking, mass is invariant.

George

Date: 25 Oct 2006 04:54:39
From: George Dishman
Subject: Re: infinite pill-shaped universe?

William.Mook@gmail.com wrote:
> George Dishman wrote:
> > William.Mook@gmail.com wrote:
> > > Momentum, mass, the galilean notion of relativity, the newtonian notion
> > > of absolute time, - all those aspects of every-day science and
> > > engineering, are hard-wired into our brains.
> >
> > I completely agree, but nature is not so limited
>
> I agree with this.
>
> > and
> > our mathematical description of it should not be so
> > constrained.
>
> Our mathematical description is NOT constrained, and I never said
> anything about our mathematical description, so your point is moot.

I didn't suggest you did, the point remains valid.

> > > You folks make absolute statements that are highly suspect, or plain
> > > wrong, (as when I was told to try again by one poster at one point when
> > > I merely said momentum was mass times velocity! haha.. )
> >
> > That was me, I assumed you knew the answer since
> > you seemed familiar with SR.
>
> I am intimately familiar with special relativity among other things, so
> your presumption that I am wrong is itself wrong! And your statement
> was wrong in the context of my discussion anway.

The context of the discussion is the use of invariant
mass versus "relativistic mass" in SR.

> > The correct equation is:
>
> What is correct and what is not correct depends on the context of our
> discussion. You presume our disagreement stems from my lack of
> knowledge,

I presume no such thing, I believe our disagreement
reflects a change in teaching practice over the last
few decades to get away from the old pseudo-
Newtonian approach to a more fully relativistic
treatment.

> when in reality it stems from your lack of appreciation of
> certain important details in your thought process about knowledge we
> both share..
>
> > p = m [ v c / sqrt(c^2 - v^2) ]
>
> In the context of special relativity this equation has certain
> important meaning. It might be said to be correct in certain contexts.

Indeed, it is obviously only valid for massive objects
and inappropriate for photons, but in the context of
discussing "relativistic mass" it is correct.

> In the low speed context with v << c the statement mass times velocity
> is close enough to be said to be true.

It is close enough to be a useable approximation of
course, but our context was the use of "relativistic
mass" which is specifically used where the
approximation p ~ m v is not adequate.

> For example, if you set c=1 and v=1/1000000 then p = mv is true to one
> part in 5 x 10^-15 If you had a gram of copper and wished to calculate
> the momentum of a gram of the stuff moving at 300 m/sec the difference
> between p=mv and the 'correct' SR formula the error would amount to 5 x
> 10^-15 grams of material. Since the atomic weight of copper is 63.546
> amu, this amounts to 47,367,261 atoms difference, which is
> substantially correct in any realistic since. So, the Newtonian
> equation is obviously an important equation since this is what our
> brains are hardwired to know intuitively -

Our brains are hardwired to know intuitively that
momentum is a linear function of speed as v
approaches c? I don't think so.

> and by referencing this
> equation in our discussion of relativity, our intuitive knowledge is
> tapped to deepen and enrich our understanding of relativity.
>
>
> > or mass multiplied by a slightly more complex function
> > of speed.
>
> Yes, but its a moot point in the context of my earlier discussion as
> I've already pointed out.
>
> > Of course you can group it like this
> >
> > p = [ m c / sqrt(c^2 - v^2) ] v
> >
> > and call the term in square brackets "relativistic mass"
>
> Yes, which allows you to make important connections to your intuitive
> understanding of reality. This explains why it was done this way at the
> outset in our history of learning about the universe.
>
> > but it is just a cludge to allow the old Newtonian equation
> > to be used in a relativistic situation.
>
> If your goal is isolate your intellect from your intuition this is a
> way to proceed. I prefer a more integrative approach since it provides
> the basis of a richer understanding by tapping the into the depths of
> what humans are. As I've already explained about 10x

My goal was to ensure that the lurkers who may
follow these conversations and aren't as familiar
with SR as you are not misled into thinking that
mass varies with speed and are instead aware
that the anachronistic "relativistic mass" is a
composite term which includes the actual invariant
mass and a speed-dependent term which is
frequently associated with the mass in the real
equations. You are welcome to use whatever
approach you like of course.

George

Date: 11 Oct 2006 13:45:30
From: stapleton
Subject: Re: infinite pill-shaped universe?

"stapleton" <alier342@silverman.com > wrote in message
news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
>
> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
>> stapleton wrote:
>>>
>>> I think its beyond our ability to understand in human terms.
>>> Time and space do not exist outside of the "expanding universe".
>>
>> Excuse me but if "its beyond our ability to understand in human terms"
>> then it is NOT SCIENCE but religion.
>
> There are ALOT of things in science that are not understandable in human
> terms.
> Take a class in quantum mechanics. You see crazy formulas like:
> time * space = mass * energy * Si (Si is a constant)
>
> There are even more thinks in science that are hard to comprehend.
>
> Such as general relativity theory.
> As an object approaches the speed of light, its mass becomes infinite and
> time slows.
>
> Just trying to imagine the mass of a teaspoon of matter form a black hole
> is impossible to imagine. It would be so heavy it would sink to the center
> of the earth, keep going, and rebounce multiple times before coming to
> rest
> at the center.
>
> Or Nuetrinos. They pass through the earth as if the earth were thin air.
>
> etc ....

http://einstein.stanford.edu/content/relativity/q25.html
Perhaps no other concept in all of physics is as impossible to comprehend as
curvature of space,
let alone the curvature of space-time. The equivalency between curvature and
gravitational forces
also appears profoundly counter-intuitive...

Date: 24 Oct 2006 06:54:53
From: George Dishman
Subject: Re: infinite pill-shaped universe?

William.Mook@gmail.com wrote:
> Momentum, mass, the galilean notion of relativity, the newtonian notion
> of absolute time, - all those aspects of every-day science and
> engineering, are hard-wired into our brains.

I completely agree, but nature is not so limited and
our mathematical description of it should not be so
constrained.

> You folks make absolute statements that are highly suspect, or plain
> wrong, (as when I was told to try again by one poster at one point when
> I merely said momentum was mass times velocity! haha.. )

That was me, I assumed you knew the answer since
you seemed familiar with SR. The correct equation is:

p = m [ v c / sqrt(c^2 - v^2) ]

or mass multiplied by a slightly more complex function
of speed.

Of course you can group it like this

p = [ m c / sqrt(c^2 - v^2) ] v

and call the term in square brackets "relativistic mass"
but it is just a cludge to allow the old Newtonian equation
to be used in a relativistic situation.

George

Date: 24 Oct 2006 20:02:56
From:
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> William.Mook@gmail.com wrote:
> > Momentum, mass, the galilean notion of relativity, the newtonian notion
> > of absolute time, - all those aspects of every-day science and
> > engineering, are hard-wired into our brains.
>
> I completely agree, but nature is not so limited

I agree with this.

> and
> our mathematical description of it should not be so
> constrained.

Our mathematical description is NOT constrained, and I never said
anything about our mathematical description, so your point is moot.

> > You folks make absolute statements that are highly suspect, or plain
> > wrong, (as when I was told to try again by one poster at one point when
> > I merely said momentum was mass times velocity! haha.. )
>
> That was me, I assumed you knew the answer since
> you seemed familiar with SR.

I am intimately familiar with special relativity among other things, so
your presumption that I am wrong is itself wrong! And your statement
was wrong in the context of my discussion anway.

> The correct equation is:

What is correct and what is not correct depends on the context of our
discussion. You presume our disagreement stems from my lack of
knowledge, when in reality it stems from your lack of appreciation of
certain important details in your thought process about knowledge we
both share..

> p = m [ v c / sqrt(c^2 - v^2) ]

In the context of special relativity this equation has certain
important meaning. It might be said to be correct in certain contexts.

In the low speed context with v << c the statement mass times velocity
is close enough to be said to be true.

For example, if you set c=1 and v=1/1000000 then p = mv is true to one
part in 5 x 10^-15 If you had a gram of copper and wished to calculate
the momentum of a gram of the stuff moving at 300 m/sec the difference
between p=mv and the 'correct' SR formula the error would amount to 5 x
10^-15 grams of material. Since the atomic weight of copper is 63.546
amu, this amounts to 47,367,261 atoms difference, which is
substantially correct in any realistic since. So, the Newtonian
equation is obviously an important equation since this is what our
brains are hardwired to know intuitively - and by referencing this
equation in our discussion of relativity, our intuitive knowledge is
tapped to deepen and enrich our understanding of relativity.

> or mass multiplied by a slightly more complex function
> of speed.

Yes, but its a moot point in the context of my earlier discussion as
I've already pointed out.

> Of course you can group it like this
>
> p = [ m c / sqrt(c^2 - v^2) ] v
>
> and call the term in square brackets "relativistic mass"

Yes, which allows you to make important connections to your intuitive
understanding of reality. This explains why it was done this way at the
outset in our history of learning about the universe.

> but it is just a cludge to allow the old Newtonian equation
> to be used in a relativistic situation.

If your goal is isolate your intellect from your intuition this is a
way to proceed. I prefer a more integrative approach since it provides
the basis of a richer understanding by tapping the into the depths of
what humans are. As I've already explained about 10x

> George

Date: 24 Oct 2006 06:05:43
From:
Subject: Re: infinite pill-shaped universe?

Momentum, mass, the galilean notion of relativity, the newtonian notion
of absolute time, - all those aspects of every-day science and
engineering, are hard-wired into our brains.

Here's the proof. I'll do a simple experiment.

Someone at a job site asked me for an apple. I threw an apple in their
direction. They watched me throw is and grabbed it from the air.

They did this naturally and easily because of the hardwiring in their
brain.

Want to do your own experiment? Learn to juggle three balls easily.
Try it. Its fun, and entertaining! And a practical demonstration of
your innate ability to solve complex problems in Newtonian motion in
real-time.

The ability to predict the precise location of an object flying
ballistically through a gravity field short distances at low speed,-
directly without calculation, as in placing your hand in a position to
catch the object - is a practical demonstration of our hard-wired
understanding of Newtonian/Galilean physics.

Appealing to this innate ability gives knowledge derived from it a
solid grounding in real world experience.

You folks make absolute statements that are highly suspect, or plain
wrong, (as when I was told to try again by one poster at one point when
I merely said momentum was mass times velocity! haha.. ) or are
tangential to the point and obscure clear discussion.

Date: 09 Oct 2006 13:30:42
From: CptDondo
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
>
> The universe cannot have both come out of the Big Bang and be infinite.
> It has to be one or the other.

Sure it can. You can have a shape with an infinite volume but a finite
boundary, and vice-versa.

Date: 09 Oct 2006 13:23:02
From: Liam
Subject: Re: infinite pill-shaped universe?

Hagar wrote:
> "Liam" <news@celticbear.com> wrote in message
> news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
> > Just found this CNN article where measured cosmic radioactivity seems
> > to indicate the universe is pill-shaped:
> > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> >
> > Now, I've just come to grips with the concept of the universe being
> > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > an infinitely thick skin of a balloon.
> >
> > Now this pill-shaped thing? I can't reconcile this in my mind.
> >
> > Could someone help me understand how both of these can be true, or
> > whether one theory undermines the other?
> >
> > Thanks!
> > Liam
> >
>
> What if the early Universe had an axial spin to it and with that spin, it
> had developed a slight equatorial bulge, pretty much like Earth has. Now if
> that spin were to slow down over time, could it create the opposite of a,
> equatorial bulge, something like an equatorial waist, which would give it a
> pill-shaped, somewhat oblong appearance, or would it still remain a sphere
> ??

But the question remains, how can an infinite universe have a finite
and discernable shape?

Date: 09 Oct 2006 13:21:04
From: Dana
Subject: Re: infinite pill-shaped universe?

"Liam" <news@celticbear.com > wrote in message
news:1160425382.126804.139250@k70g2000cwa.googlegroups.com...
>
> Hagar wrote:
> > "Liam" <news@celticbear.com> wrote in message
> > news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
> > > Just found this CNN article where measured cosmic radioactivity seems
> > > to indicate the universe is pill-shaped:
> > > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> > >
> > > Now, I've just come to grips with the concept of the universe being
> > > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > > an infinitely thick skin of a balloon.
> > >
> > > Now this pill-shaped thing? I can't reconcile this in my mind.
> > >
> > > Could someone help me understand how both of these can be true, or
> > > whether one theory undermines the other?
> > >
> > > Thanks!
> > > Liam
> > >
> >
> > What if the early Universe had an axial spin to it and with that spin,
it
> > had developed a slight equatorial bulge, pretty much like Earth has.
Now if
> > that spin were to slow down over time, could it create the opposite of
a,
> > equatorial bulge, something like an equatorial waist, which would give
it a
> > pill-shaped, somewhat oblong appearance, or would it still remain a
sphere
> > ??
>
> But the question remains, how can an infinite universe have a finite
> and discernable shape?
>

I was also going to ask about the claim that the universe is boundless.
By saying the universe has some kind of definite shape, that implies
boundaries.
Or is the boundless part of the thought that the universe will be expanding
without any end that we can see or determine.
What I am trying to say is that the Universe was considered boundless, even
when the scientists thought the universe would eventualy implode, no we know
that the universe will probably always expand. So that is why I ask about
the boundless remark. What exactly are they saying by using boundless.

Date: 09 Oct 2006 15:39:01
From: Brian Tung
Subject: Re: infinite pill-shaped universe?

Dana wrote:
> I was also going to ask about the claim that the universe is boundless.
> By saying the universe has some kind of definite shape, that implies
> boundaries.

Not in the way they mean "boundaries." For instance, the Earth has a
certain shape--almost an oblate spheroid, though ever so slightly fatter
in the southern hemisphere than in the northern. However, the *surface*
of the Earth has no boundaries--there's no "edge" to the Earth. As we
move throughout the universe, our motion is analogous to moving along
the surface of the Earth, so there's no edge to the universe, either.

You should probably take notions of the shape of the universe with a
grain of salt. All cosmological topology is done by measuring certain
properties from within the universe itself; for obvious reasons, no one
has so far been able to exit the universe and look at it from the
outside. So when people say the universe has such-and-such a shape, it
means *as inferred from internal observations*.

For instance, how would you determine that the Earth was spherical if
you could only look down at the ground? One thing you could do, in
principle, is to draw a large triangle, with sides as straight as you
could make them. Nonetheless, you would find, after making precise
measurements, that your angles added up to something more than 180
degrees (the excess being more the bigger the triangle was). This
idea of measuring the local geometry without seeing it embedded in any
larger space (the three-dimensional space of the solar system, in this
case) is something relatively new; it evolved around the turn of the
20th century.

Now, the surface of the Earth is basically a two-dimensional surface--
what mathematicians call a manifold--embedded in three-dimensional
space. The sphere we call it is something we see in three dimensions.
So, in order to properly apprehend the universe in that way, we have to
jump up one dimension (at least): it's a three-dimensional "surface" or
manifold. If it's embedded in any higher space--and this business about
measuring it locally from the inside means there doesn't *have* to be--
then that higher space must have at least four dimensions. So it's not
a pill the way you're used to thinking about pills; this pill has at
least four dimensions.

You might think about it like this. If you were to freeze the universe
(stop it from expanding) and shoot off a beam of light, then eventually,
in principle, that beam of light would hit you in the back some time
later. How much later? That time is sort of a measure of the girth,
the circumference, of the universe. When it is said that the universe
is pill-shaped, it might be better to think of that girth as depending
on the direction in which you shoot that beam of light. If you shoot
it in *this* direction, it's shorter; if you shoot it in that direction,
it's longer. Possibly, if you shoot it in other directions, it doesn't
get back to you at all, because the universe isn't curved the right way.
(If you have a big pill-shaped object, you might only be able to wrap it
in three ways--along its length, its width, and its height.)

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 09 Oct 2006 14:53:32
From: Dana
Subject: Re: infinite pill-shaped universe?

"Brian Tung" <brian@isi.edu > wrote in message
news:egej25$ui9$1@praesepe.isi.edu...
> Dana wrote:
> > I was also going to ask about the claim that the universe is boundless.
> > By saying the universe has some kind of definite shape, that implies
> > boundaries.
>
> Not in the way they mean "boundaries." For instance, the Earth has a
> certain shape--almost an oblate spheroid, though ever so slightly fatter
> in the southern hemisphere than in the northern. However, the *surface*
> of the Earth has no boundaries--there's no "edge" to the Earth. As we
> move throughout the universe, our motion is analogous to moving along
> the surface of the Earth, so there's no edge to the universe, either.
>
> You should probably take notions of the shape of the universe with a
> grain of salt. All cosmological topology is done by measuring certain
> properties from within the universe itself; for obvious reasons, no one
> has so far been able to exit the universe and look at it from the
> outside. So when people say the universe has such-and-such a shape, it
> means *as inferred from internal observations*.
>
> For instance, how would you determine that the Earth was spherical if
> you could only look down at the ground? One thing you could do, in
> principle, is to draw a large triangle, with sides as straight as you
> could make them. Nonetheless, you would find, after making precise
> measurements, that your angles added up to something more than 180
> degrees (the excess being more the bigger the triangle was). This
> idea of measuring the local geometry without seeing it embedded in any
> larger space (the three-dimensional space of the solar system, in this
> case) is something relatively new; it evolved around the turn of the
> 20th century.
>
> Now, the surface of the Earth is basically a two-dimensional surface--
> what mathematicians call a manifold--embedded in three-dimensional
> space. The sphere we call it is something we see in three dimensions.
> So, in order to properly apprehend the universe in that way, we have to
> jump up one dimension (at least): it's a three-dimensional "surface" or
> manifold. If it's embedded in any higher space--and this business about
> measuring it locally from the inside means there doesn't *have* to be--
> then that higher space must have at least four dimensions. So it's not
> a pill the way you're used to thinking about pills; this pill has at
> least four dimensions.
>
> You might think about it like this. If you were to freeze the universe
> (stop it from expanding) and shoot off a beam of light, then eventually,
> in principle, that beam of light would hit you in the back some time
> later. How much later? That time is sort of a measure of the girth,
> the circumference, of the universe. When it is said that the universe
> is pill-shaped, it might be better to think of that girth as depending
> on the direction in which you shoot that beam of light. If you shoot
> it in *this* direction, it's shorter; if you shoot it in that direction,
> it's longer. Possibly, if you shoot it in other directions, it doesn't
> get back to you at all, because the universe isn't curved the right way.
> (If you have a big pill-shaped object, you might only be able to wrap it
> in three ways--along its length, its width, and its height.)

Excellent explanation.
You answered a few of my questions with the above.

>
> --
> Brian Tung <brian@isi.edu>
> The Astronomy Corner at http://astro.isi.edu/
> Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
> The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
> My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 13 Oct 2006 22:27:05
From: Peter Webb
Subject: Re: infinite pill-shaped universe?

I agree - a very well worded explanation.

Date: 13 Oct 2006 16:14:39
From: Sorcerer
Subject: Re: infinite pill-shaped universe?

"Peter Webb" <webbfamily-diespamdie@optusnet.com.au > wrote in message
news:452f861b$0$22937$afc38c87@news.optusnet.com.au...

Date: 09 Oct 2006 17:13:22
From: Michael McCulloch
Subject: Re: infinite pill-shaped universe?

On 9 2006 13:23:02 -0700, "Liam" <news@celticbear.com > wrote:

>But the question remains, how can an infinite universe have a finite
>and discernable shape?

I think the idea of "shape" has more to do with how radiation moves in
the space of the Universe rather than any boundary shape of the whole.

For example, if the Universe is flat, then light travels in straight
lines through the Universe unless locally influenced by gravity.

---
Michael McCulloch

Date: 10 Oct 2006 18:21:58
From: jacob navia
Subject: Re: infinite pill-shaped universe?

Liam wrote:
> Hagar wrote:
>
>>"Liam" <news@celticbear.com> wrote in message
>>news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
>>
>>>Just found this CNN article where measured cosmic radioactivity seems
>>>to indicate the universe is pill-shaped:
>>>http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>>
>>>Now, I've just come to grips with the concept of the universe being
>>>infinite and expanding out of a Big...Expanding like "raisin bread" or
>>>an infinitely thick skin of a balloon.
>>>
>>>Now this pill-shaped thing? I can't reconcile this in my mind.
>>>
>>>Could someone help me understand how both of these can be true, or
>>>whether one theory undermines the other?
>>>
>>>Thanks!
>>>Liam
>>>
>>
>>What if the early Universe had an axial spin to it and with that spin, it
>>had developed a slight equatorial bulge, pretty much like Earth has. Now if
>>that spin were to slow down over time, could it create the opposite of a,
>>equatorial bulge, something like an equatorial waist, which would give it a
>>pill-shaped, somewhat oblong appearance, or would it still remain a sphere
>>??
>
>
> But the question remains, how can an infinite universe have a finite
> and discernable shape?
>

RIGHT!!!

IT IS IMPOSSIBLE!!!

Date: 09 Oct 2006 13:19:21
From: Hagar
Subject: Re: infinite pill-shaped universe?

"Liam" <news@celticbear.com > wrote in message
news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
> Just found this CNN article where measured cosmic radioactivity seems
> to indicate the universe is pill-shaped:
> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
> Now, I've just come to grips with the concept of the universe being
> infinite and expanding out of a Big...Expanding like "raisin bread" or
> an infinitely thick skin of a balloon.
>
> Now this pill-shaped thing? I can't reconcile this in my mind.
>
> Could someone help me understand how both of these can be true, or
> whether one theory undermines the other?
>
> Thanks!
> Liam
>

What if the early Universe had an axial spin to it and with that spin, it
had developed a slight equatorial bulge, pretty much like Earth has. Now if
that spin were to slow down over time, could it create the opposite of a,
equatorial bulge, something like an equatorial waist, which would give it a
pill-shaped, somewhat oblong appearance, or would it still remain a sphere
??

Date: 09 Oct 2006 13:25:13
From: CptDondo
Subject: Re: infinite pill-shaped universe?

Hagar wrote:
> "Liam" <news@celticbear.com> wrote in message
> news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
>> Just found this CNN article where measured cosmic radioactivity seems
>> to indicate the universe is pill-shaped:
>> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>
>> Now, I've just come to grips with the concept of the universe being
>> infinite and expanding out of a Big...Expanding like "raisin bread" or
>> an infinitely thick skin of a balloon.
>>
>> Now this pill-shaped thing? I can't reconcile this in my mind.
>>
>> Could someone help me understand how both of these can be true, or
>> whether one theory undermines the other?
>>
>> Thanks!
>> Liam
>>
>
> What if the early Universe had an axial spin to it and with that spin, it
> had developed a slight equatorial bulge, pretty much like Earth has. Now if
> that spin were to slow down over time, could it create the opposite of a,
> equatorial bulge, something like an equatorial waist, which would give it a
> pill-shaped, somewhat oblong appearance, or would it still remain a sphere
> ??
>
>

Long ago, I wrote a 4-D cad system. I could pretty much show you a
large number of shapes; diamond-like, box-like, square like, tube-like -
and they all were the same thing, a projection of a 4D object onto 3
dimensions, and then onto a 2D screen.

It's meaningless to talk about a 'shape' when there is no frame of
reference to judge that shape by. I personally hope we're in a Marilyn
Monroe universe, complete with red velvet backdrop. Makes about as much
sense as a pill.....

Date: 10 Oct 2006 18:24:29
From: jacob navia
Subject: Re: infinite pill-shaped universe?

CptDondo wrote:
> Hagar wrote:
>
>> "Liam" <news@celticbear.com> wrote in message
>> news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
>>
>>> Just found this CNN article where measured cosmic radioactivity seems
>>> to indicate the universe is pill-shaped:
>>> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>>
>>> Now, I've just come to grips with the concept of the universe being
>>> infinite and expanding out of a Big...Expanding like "raisin bread" or
>>> an infinitely thick skin of a balloon.
>>>
>>> Now this pill-shaped thing? I can't reconcile this in my mind.
>>>
>>> Could someone help me understand how both of these can be true, or
>>> whether one theory undermines the other?
>>>
>>> Thanks!
>>> Liam
>>>
>>
>> What if the early Universe had an axial spin to it and with that spin,
>> it had developed a slight equatorial bulge, pretty much like Earth
>> has. Now if that spin were to slow down over time, could it create
>> the opposite of a, equatorial bulge, something like an equatorial
>> waist, which would give it a pill-shaped, somewhat oblong appearance,
>> or would it still remain a sphere ??
>>
>
> Long ago, I wrote a 4-D cad system. I could pretty much show you a
> large number of shapes; diamond-like, box-like, square like, tube-like -
> and they all were the same thing, a projection of a 4D object onto 3
> dimensions, and then onto a 2D screen.
>
> It's meaningless to talk about a 'shape' when there is no frame of
> reference to judge that shape by. I personally hope we're in a Marilyn
> Monroe universe, complete with red velvet backdrop. Makes about as much
> sense as a pill.....

EXACTLY!!!

All this talk about the univers's shape is just NONSENSE!!!
A shape implies a boundary, and the universe has no boundaries.

Date: 10 Oct 2006 16:19:22
From: CptDondo
Subject: Re: infinite pill-shaped universe?

jacob navia wrote:

>> It's meaningless to talk about a 'shape' when there is no frame of
>> reference to judge that shape by. I personally hope we're in a
>> Marilyn Monroe universe, complete with red velvet backdrop. Makes
>> about as much sense as a pill.....
>
> EXACTLY!!!
>
> All this talk about the univers's shape is just NONSENSE!!!
> A shape implies a boundary, and the universe has no boundaries.
>

It's appropriate to talk about a curvature of space, but not a 'shape'
of the universe.

--Yan

Date: 11 Oct 2006 00:40:54
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"CptDondo" <yan@NsOeSiPnAeMr.com > wrote in message
news:12ioajic4garf0c@corp.supernews.com...
> jacob navia wrote:
>
>>> It's meaningless to talk about a 'shape' when there is no frame of
>>> reference to judge that shape by. I personally hope we're in a Marilyn
>>> Monroe universe, complete with red velvet backdrop. Makes about as much
>>> sense as a pill.....
>>
>> EXACTLY!!!
>>
>> All this talk about the univers's shape is just NONSENSE!!!
>> A shape implies a boundary, and the universe has no boundaries.
>>
>
> It's appropriate to talk about a curvature of space, but not a 'shape' of
> the universe.

A brief read of the article suggests they are describing
the shape of the surface of last scattering, i.e. the
limits of the observable part of the universe only.

George

Date: 10 Oct 2006 17:40:20
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear George Dishman:

"George Dishman" <george@briar.demon.co.uk > wrote in message
news:egha6h$bl7$1@news.freedom2surf.net...
...
> A brief read of the article suggests they are describing
> the shape of the surface of last scattering, i.e. the
> limits of the observable part of the universe only.

Any discussion of which way the "pill" is oriented... say with
respect to the CMBR anisotropy? Wondering if length contraction
has any contribution one way or the other. 300 km/sec is not
enough to yield a 1% contraction, but you never know...

David A. Smith

Date: 10 Oct 2006 18:21:07
From: jacob navia
Subject: Re: infinite pill-shaped universe?

Date: 10 Oct 2006 09:04:21
From: Hagar
Subject: Re: infinite pill-shaped universe?

"Liam" <news@celticbear.com > wrote in message
news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
> Just found this CNN article where measured cosmic radioactivity seems
> to indicate the universe is pill-shaped:
> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
> Now, I've just come to grips with the concept of the universe being
> infinite and expanding out of a Big...Expanding like "raisin bread" or
> an infinitely thick skin of a balloon.
>
> Now this pill-shaped thing? I can't reconcile this in my mind.
>
> Could someone help me understand how both of these can be true, or
> whether one theory undermines the other?
>
> Thanks!
> Liam

Perhaps the early Universe (omni-directionally infinite and very empty)
developed a case of ADD (Attention Deficit Disorder) because there was
nothing to do. So that Intelligent Design Dude blew up some stuff and made
it look like a bid, appetizing Ritalin pill, hoping to entice the Universe
to swallow it. Unfortunately, the Cosmos, like a playful kitten, just
started batting it around, creating the chaos we observe today.

Date: 10 Oct 2006 18:25:18
From: jacob navia
Subject: Re: infinite pill-shaped universe?

Hagar wrote:
> "Liam" <news@celticbear.com> wrote in message
> news:1160423445.892101.40190@m7g2000cwm.googlegroups.com...
>
>>Just found this CNN article where measured cosmic radioactivity seems
>>to indicate the universe is pill-shaped:
>>http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>
>>Now, I've just come to grips with the concept of the universe being
>>infinite and expanding out of a Big...Expanding like "raisin bread" or
>>an infinitely thick skin of a balloon.
>>
>>Now this pill-shaped thing? I can't reconcile this in my mind.
>>
>>Could someone help me understand how both of these can be true, or
>>whether one theory undermines the other?
>>
>>Thanks!
>>Liam
>
>
> Perhaps the early Universe (omni-directionally infinite and very empty)
> developed a case of ADD (Attention Deficit Disorder) because there was
> nothing to do. So that Intelligent Design Dude blew up some stuff and made
> it look like a bid, appetizing Ritalin pill, hoping to entice the Universe
> to swallow it. Unfortunately, the Cosmos, like a playful kitten, just
> started batting it around, creating the chaos we observe today.
>
>
You should receive the Nobel Prize ASAP!

Date: 11 Oct 2006 00:24:29
From: Mary Poppins
Subject: Re: infinite pill-shaped universe?

Date: 11 Oct 2006 05:55:47
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear Mary Poppins:

"Mary Poppins" <gandol@hgnet.org > wrote in message
news:452C800D.3BDC9B69@hgnet.org...
>
> Liam wrote:
>
>> Just found this CNN article where measured cosmic
>> radioactivity seems to indicate the universe is pill-shaped:
>> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>>
>> Now, I've just come to grips with the concept of the
>> universe being infinite and expanding out of a Big...
>> Expanding like "raisin bread" or an infinitely thick
>> skin of a balloon.
>>
>> Now this pill-shaped thing? I can't reconcile this in
>> my mind.
>>
>> Could someone help me understand how both of
>> these can be true, or whether one theory
>> undermines the other?
>
> In what size prescription for how much?

Your prescription is all that you can see. You'll take it for
the rest of your life, just like thyroid or insulin.

> Will it bankrupt me?

You won't take anything with you when you go.

Better question... is it covered by insurance/government benefit?
; >)

David A. Smith

Date: 11 Oct 2006 20:30:19
From:
Subject: Re: infinite pill-shaped universe?

rest mass is an invariant. mass is not since it varies with speed.

Date: 11 Oct 2006 21:25:47
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear William.Mook:

<William.Mook@gmail.com > wrote in message
news:1160623819.805199.226900@c28g2000cwb.googlegroups.com...
> rest mass is an invariant. mass is not since it varies
> with speed.

Mass does not vary with speed. Mass is not a vector, yet
relativistic mass does not correctly describe how a charge
accelerates in a magnetic field.

No *current* physics textbook uses mass for anything except rest
mass.

Baez says mass is rest mass:
http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
Hillman says mass is rest mass:
http://groups.google.com/group/sci.physics/msg/6f1f1b991a0e6c26
Taylor and Wheeler say mass is rest mass:
"Spacetime Physics"
Gary Oas says mass is rest mass:
http://adsabs.harvard.edu/abs/2005physics...4110O
... and here
http://arxiv.org/abs/physics/0504110

... a mixed bag on this site...
http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html#mas
... with lots of disclaimers.

Your usage is non standard, you will get in trouble if you try
and use formulae based on mass = rest mass. And exclamations of
"bullshit" are unconvincing. And hints that everyone else
doesn't understand special relativity should give you a clue...

Believe what you will. I just wish you didn't spread antiquated
usage around like it was gospel.

David A. Smith

Date: 12 Oct 2006 06:49:39
From: Sorcerer
Subject: Re: infinite pill-shaped universe?

"N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com > wrote in
message news:7tjXg.3282$v43.3259@fed1read02...

Date: 11 Oct 2006 20:28:07
From:
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
>
> Yup! Modern physics has consigned "relativistic mass" to the scrap
> heap along with "aether".
>

Bullshit

Date: 11 Oct 2006 20:27:14
From:
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160590946.125364.61000@b28g2000cwb.googlegroups.com...
> > Mass is not an invariant quantity, it changes with relative speed.
> > That's what the special and general theory of relativity is all about.
> >
> > The mass of a particle at rest can be invariant. But the mass of a
> > particle in motion changes with its speed. You can see this with
> > electrons in a vacuum tube flying through a magnetic field. This is a
> > typical experiment (or was) that is done in college level physics
> > classes.
> >
> > You have a vacuum tube with an electron gun at one end and a phosphor
> > screen at another. You can change the voltage of the electron gun, and
> > thus, change the velocity of the electrons flying out of the end of the
> > gun. A spot of light glows at the point on the phosphor screen where
> > the electrons strike the phosphor. You can then apply a magnetic field
> > to the electron beam and cause the electrons to be accelerated through
> > an angle, shifting the location of the glowing spot.
> >
> > This is a cool apparatus because you can learn so much about things
> > with it. Knowing a few principles of geometry and electrostatics and
> > electrodynamics, you can weigh electrons, measure their speed and so
> > forth.
> >
> > You can vary the speed of the electrons from about 1% the speed of
> > light to about 90% the speed of light by changing the voltage of the
> > gun from 1,000V to about 100,000V.
> >
> > Once you do a few of these introductory experiments, you can then crank
> > up the voltage and deflect the beam of very high speed electrons and
> > measure their mass at speed. When you do this you see experimental
> > proof that Lorentz effects are real. That is, the mass of a moving
> > electron is far greater than a stationary electron.
> >
> > Now at this point in the course you see an old NSF film that shows that
> > mu-mesons produced by cosmic rays high in the Earth's atmosphere
> > wouldn't make it to the ground unless time to were distorted as
> > described in the Lorentz equations. The coup'd grace is an experiment
> > done in lecture that actually measures mu-mesons coursing through the
> > lecture hall from cosmic space! oooooo...
> >
> > It makes all this bs that people argue endlessly about here stand out
> > for what it is! lol.
>
> Everything you say about the experiments is true and yes
> the effects are real, but in the modern approach mass is
> treated as invariant and the gamma function is treated as
> part of the relation between mass,

REST MASS can be treated as an invariant. MASS cannot. Sorry, you
really don't understand the special theory of relativity if you do not
get this.

http://www.physics.nyu.edu/hogg/sr/sr.pdf

> speed and energy. The
> concept of "relativistic mass" which you describe is
> nowadays seen as being anachronistic even if still useful
> in practical terms.

Relativistic mass is important in any discussion of relativity. Sorry.

Date: 12 Oct 2006 07:43:56
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1160623634.485937.131340@m7g2000cwm.googlegroups.com...
>
> George Dishman wrote:

<snip >

>> Everything you say about the experiments is true and yes
>> the effects are real, but in the modern approach mass is
>> treated as invariant and the gamma function is treated as
>> part of the relation between mass,
>
> REST MASS can be treated as an invariant. MASS cannot. Sorry, you
> really don't understand the special theory of relativity if you do not
> get this.
>
> http://www.physics.nyu.edu/hogg/sr/sr.pdf

Excellent document. It only mentions "relativistic mass" once,
see the first paragraph of section 6.4:

"Just as in non-relativistic 3-space, where 3-momentum
was defined as mass times 3-velocity, in spacetime
4-momentum ~p is mass m times 4-velocity ~u. Under this
definition, the mass must be a scalar if the 4-momentum
is going to be a 4-vector. If you are old enough, you may
have heard of a quantity called "relativistic mass" which
increases with velocity, approaching infinity as an object
approaches the speed of light. Forget whatever you heard;
that formulation of special relativity is archaic and ugly.
The mass m of an object as far as we are concerned is its
rest mass, or the mass we would measure if we were at
rest with respect to the object."

>> speed and energy. The
>> concept of "relativistic mass" which you describe is
>> nowadays seen as being anachronistic even if still useful
>> in practical terms.
>
> Relativistic mass is important in any discussion of relativity. Sorry.

"Forget whatever you heard; that formulation of special
relativity is archaic and ugly."

George

Date: 27 Oct 2006 05:46:00
From:
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> William.Mook@gmail.com wrote:
> > Wow, George, you are an argumentative old cuss... hmm...
>
> 'Fraid so ;-)

Welcome to the club!

>
> However, let me remind you of your comment that
> started all this. You wrote in message:
> http://groups.google.co.uk/group/sci.astro/msg/5ab9a4a05fdf1593
>
> > Mass is not an invariant quantity, it changes with relative speed.
> > That's what the special and general theory of relativity is all about.
> >
> > The mass of a particle at rest can be invariant. But the mass of a
> > particle in motion changes with its speed. You can see this with
> > electrons in a vacuum tube ...
>
> Mass varying with speed is most definitely not "what
> the special and general theory of relativity is all about."

Yes it is. We think of mass as a constant unvarying with speed. The
apparent change of mass at high speeds demands an explanation! Which
gives us the 4-form of unvarying mass rotating in 4-space, projected
onto 3-space as a 3-form with apparently varying mass.

> nor IMO is it a good way to start learning what SR or
> GR are really about.

We disagree here.

> > George Dishman wrote:
> > > William.Mook@gmail.com wrote:
> > > > George Dishman wrote:
> > > > > William.Mook@gmail.com wrote:
> > > > > > Momentum, mass, the galilean notion of relativity, the newtonian notion
> > > > > > of absolute time, - all those aspects of every-day science and
> > > > > > engineering, are hard-wired into our brains.
> > > > >
> > > > > I completely agree, but nature is not so limited
> > > >
> > > > I agree with this.
> > > >
> > > > > and
> > > > > our mathematical description of it should not be so
> > > > > constrained.
> > > >
> > > > Our mathematical description is NOT constrained, and I never said
> > > > anything about our mathematical description, so your point is moot.
> > >
> > > I didn't suggest you did, the point remains valid.
> >
> > You are confused here. I never suggested we should constrain our
> > mathematical descriptions.
>
> I know, and I didn't say you did, so now who's being
> argumentative?

I don't know since your reply is very confusing since all context is
lost.

> If you want to push the point, what I
> was saying is that, for example, we shouldn't cast
> our equation for momentum is this form:
>
> p = m_r * v
>
> from which we must have
>
> m_r = m c / sqrt(c^2 - v^2)
>
> only to be compliant with everday experience.

You don't value the depth of everyday experience because you don't see
the deeper connections to non-intellectual experience and the value
they have.

> Much of
> modern science (and all of QM!) is counter-intuitive

Yes.

> and
> students will at some point need to break that connection.

I would say students need to MAKE the connection! lol.

> It is my feeling that writing the equation in this form:
>
> p = m [ v c / sqrt(c^2 - v^2) ]
>
> makes it much clearer that mass is an invariant scalar.
>

Yes.

> > I merely suggested that appealing to
> > intuitive notions of space and time add real depth to our understanding
> > of the mathematics.
>
> I, on the other hand, think it unnecessarily creates a
> misunderstanding, the idea that mass varies with speed.
>

Mass apparently changes with speed in the 3-form projection, this is an
important observation in making a connection to deeper experience.

> > > > > > You folks make absolute statements that are highly suspect, or plain
> > > > > > wrong, (as when I was told to try again by one poster at one point when
> > > > > > I merely said momentum was mass times velocity! haha.. )
> > > > >
> > > > > That was me, I assumed you knew the answer since
> > > > > you seemed familiar with SR.
> > > >
> > > > I am intimately familiar with special relativity among other things, so
> > > > your presumption that I am wrong is itself wrong! And your statement
> > > > was wrong in the context of my discussion anway.
> > >
> > > The context of the discussion is the use of invariant
> > > mass versus "relativistic mass" in SR.
> >
> > As a means to tap into our intuitive understanding of things, yes. I
> > didn't suggest we stop there.
>
> No, you simply said that I was wrong when I said
> the following in message
> http://groups.google.co.uk/group/sci.astro/msg/8307e0dedb0e2f49
>
> >> The FAQ:
> >>
> >> http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
> >>
> >> Scientifically speaking, mass is invariant.
>
> Again, consider what you said of that:
>

I have considered what I said. You have not! lol.

> > Mass is not an invariant quantity, it changes with relative speed.
> > That's what the special and general theory of relativity is all about.
> >
> > The mass of a particle at rest can be invariant. But the mass of a
> > particle in motion changes with its speed. ...
>
>
> > > > > The correct equation is:
> > > >
> > > > What is correct and what is not correct depends on the context of our
> > > > discussion. You presume our disagreement stems from my lack of
> > > > knowledge,
> > >
> > > I presume no such thing,
> >
> > Whenever you say something like 'the correct equation is...' presumes
> > all other modes of understanding are somehow incorrect.
>
> No, it meant that one equation:
>
> p = m [ v c / sqrt(c^2 - v^2) ]
>
> is accurate to the best of current scientific knowledge while the
>
> p = m v
>
> is only an approximation. It may be a very useful approximation
> but we shouldn't give lurkers the idea that it can be used on all
> occasions.
>
> > You should
> > really avoid brow-beating students in this way. It silences their own
> > rich understanding by assuming they have nothing to contribute merely
> > because it doesn't follow the lesson plan.
>
> I am against giving students incorrect information. Starting
> by showing
>
> p = m [ v c / sqrt(c^2 - v^2) ]
>
> and then go on to discuss the situations where p = mv
> is a valid approximation is IMO much more informative
> and aids the understaing of when use of approximations
> in general is appropriate.
>
> > > I believe our disagreement
> > > reflects a change in teaching practice over the last
> > > few decades
> >
> > A agree. Some things have changed for the worse! lol.
>
> YMMV ;-)
>
> > > to get away from the old pseudo-
> > > Newtonian approach to a more fully relativistic
> > > treatment.
> >
> > Hogwash. The new approaches merely seek to avoid the same tired old
> > questions because they're boring for teachers to handle year in and
> > year out. They're quite efficient to this end. But they have a cost,
> > and that cost is making relativity seem like a different field of
> > experience than the one they know intuitively - which isolates
> > understanding from experience - and which I judge to be a bad thing.
>
> I on the other hand think it gets them into thinking in
> a 4D way which is essential as they move into GR.
>
> > > > when in reality it stems from your lack of appreciation of
> > > > certain important details in your thought process about knowledge we
> > > > both share..
> > > >
> > > > > p = m [ v c / sqrt(c^2 - v^2) ]
> > > >
> > > > In the context of special relativity this equation has certain
> > > > important meaning. It might be said to be correct in certain contexts.
> > >
> > > Indeed, it is obviously only valid for massive objects
> > > and inappropriate for photons, but in the context of
> > > discussing "relativistic mass" it is correct.
> >
> > Except that it avoids any connection with our intuitive understanding
> > of these things evidenced by for example, juggling.
>
> If you want to be a juggler use Newton. If you want to
> work in high-energy physics or cosmology or any other
> field where SR and GR matter then you need to start
> think in 4D.
>
> > > > In the low speed context with v << c the statement mass times velocity
> > > > is close enough to be said to be true.
> > >
> > > It is close enough to be a useable approximation of
> > > course,
> >
> > Which is a starting point of richer understanding, not the end point.
>
> I disagree, IMO, it avoids understanding the true behaviour
> of nature by coating it in a veneer of Newtonian thinking.
>
> > > but our context was the use of "relativistic
> > > mass" which is specifically used where the
> > > approximation p ~ m v is not adequate.
> >
> > Except as a starting point of making connections to the intuitive
> > knowledge that exists in all learners.
>
> No, you simply said my statement
>
> >> Scientifically speaking, mass is invariant.
>
> was wrong. In fact at the ed of your post you
> implied it was "bs".
>
> > > > For example, if you set c=1 and v=1/1000000 then p = mv is true to one
> > > > part in 5 x 10^-15 If you had a gram of copper and wished to calculate
> > > > the momentum of a gram of the stuff moving at 300 m/sec the difference
> > > > between p=mv and the 'correct' SR formula the error would amount to 5 x
> > > > 10^-15 grams of material. Since the atomic weight of copper is 63.546
> > > > amu, this amounts to 47,367,261 atoms difference, which is
> > > > substantially correct in any realistic since. So, the Newtonian
> > > > equation is obviously an important equation since this is what our
> > > > brains are hardwired to know intuitively -
> > >
> > > Our brains are hardwired to know intuitively that
> > > momentum is a linear function of speed as v
> > > approaches c? I don't think so.
> >
> > You are being obtuse.
>
> It's what you seemed to be saying.
>
> > Our hardwiring doesn't understand massive objects approaching c. Our
> > hardwiring does understand our experience of moving masses in a deep
> > way - as catching a softball or juggling attest to. It is connecting
> > to that experience that I am speaking of. Tapping into deeply known
> > things is the source of much knowledge - encoded in our beings by
> > evolution. I believe we lose something by changing curricula to avoid
> > such connections merely to make the jobs of teachers easier.
>
> Whereas I believe we gain a deeper understanding by using
> our ability to visualise 3D to see how the 4D universe works
> by visualise worldlines and spacetime using an x,y,t view.
> The aim isn't to make the teacher's job easier but to give
> the students the tools they will need in their careers.
>
> > > > If your goal is isolate your intellect from your intuition this is a
> > > > way to proceed. I prefer a more integrative approach since it provides
> > > > the basis of a richer understanding by tapping the into the depths of
> > > > what humans are. As I've already explained about 10x
> > >
> > > My goal was to ensure that the lurkers who may
> > > follow these conversations and aren't as familiar
> > > with SR as you are not misled into thinking that
> > > mass varies with speed
> >
> > But that idea that mass varies with speed (or that time varies with
> > speed) can be a useful way of understanding what is going on at a deep
> > level ..
>
> At the deeper level, mass does _not_ change with
> speed, it is invariant. It only _appears_ to change when
> you assume for example that p = m v and then calculate
> m as p/v. That is the whole point, you are advocating
> teaching a concept that subsequently students will have
> to discard.
>
> > by appealing to what things seem like (if not pushed too far) - I
> > see value in maintaining that connection you do not. You see only the
> > benefit in avoiding tired old questions that lead to deeper
> > understanding among learners when those questions are answered. They
> > may be tired for us, but not for them and that's the point.
>
> No, I have no problem with the questions, it is teaching
> erroneous concepts to make life easier for the teacher
> that I am objecting to.
>
> > > and are instead aware
> > > that the anachronistic "relativistic mass" is a
> > > composite term which includes the actual invariant
> > > mass and a speed-dependent term which is
> > > frequently associated with the mass in the real
> > > equations.
> >
> > YES!
> >
> > > You are welcome to use whatever
> > > approach you like of course.
> >
> > Haha... good solid statement followed by pointless brow-beating! lol.
> > I knew it was too good to last! haha..
>
> Not "brow-beating" at all, I was merely acknowledging that
> once while one may understand the deeper aspects, it is
> perfectly reasonable and pragmatically very appropriate
> to use the old "relativistic mass" approach in getting
> numbers out of the theory.
>
> George

Date: 27 Oct 2006 18:33:39
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1161953160.339472.191130@m73g2000cwd.googlegroups.com...
>
> George Dishman wrote:
>> William.Mook@gmail.com wrote:
>> > Wow, George, you are an argumentative old cuss... hmm...
>>
>> 'Fraid so ;-)
>
> Welcome to the club!
>
>>
>> However, let me remind you of your comment that
>> started all this. You wrote in message:
>> http://groups.google.co.uk/group/sci.astro/msg/5ab9a4a05fdf1593
>>
>> > Mass is not an invariant quantity, it changes with relative speed.
>> > That's what the special and general theory of relativity is all about.
>> >
>> > The mass of a particle at rest can be invariant. But the mass of a
>> > particle in motion changes with its speed. You can see this with
>> > electrons in a vacuum tube ...
>>
>> Mass varying with speed is most definitely not "what
>> the special and general theory of relativity is all about."
>
> Yes it is.

No. SR was about producing a new model of time and
space to replace those of Newton which resolved many
of the problems in late 19th century physics. GR was
about extending that to cope with gravity to replace
Newton's "action at a distance" model.

> We think of mass as a constant unvarying with speed.

It is.

> The
> apparent change of mass at high speeds demands an explanation! Which
> gives us the 4-form of unvarying mass rotating in 4-space, projected
> onto 3-space as a 3-form with apparently varying mass.

Right, it is merely an effect of projection. That
understanding is lost when you use the relativistic
mass approach.

>> nor IMO is it a good way to start learning what SR or
>> GR are really about.
>
> We disagree here.

Indeed.

<snip >

> I don't know since your reply is very confusing since all context is
> lost.

OK, I've snipped that.

>> If you want to push the point, what I
>> was saying is that, for example, we shouldn't cast
>> our equation for momentum is this form:
>>
>> p = m_r * v
>>
>> from which we must have
>>
>> m_r = m c / sqrt(c^2 - v^2)
>>
>> only to be compliant with everday experience.
>
> You don't value the depth of everyday experience because you don't see
> the deeper connections to non-intellectual experience and the value
> they have.

I do value them, but they conflict with the deeper
understanding of the effect of projection within
a 4D viewpoint.

>> Much of
>> modern science (and all of QM!) is counter-intuitive
>
> Yes.
>
>> and
>> students will at some point need to break that connection.
>
> I would say students need to MAKE the connection! lol.
>
>> It is my feeling that writing the equation in this form:
>>
>> p = m [ v c / sqrt(c^2 - v^2) ]
>>
>> makes it much clearer that mass is an invariant scalar.
>>
>
> Yes.
>
>> > I merely suggested that appealing to
>> > intuitive notions of space and time add real depth to our understanding
>> > of the mathematics.
>>
>> I, on the other hand, think it unnecessarily creates a
>> misunderstanding, the idea that mass varies with speed.
>>
>
> Mass apparently changes with speed in the 3-form projection, this is an
> important observation in making a connection to deeper experience.

Right, it "apparently changes", as a projection only,
it is actually invariant as I said

I'll snip the rest as you didn't respond. I doubt
there's much more to say on the matter, our views
on teaching simply differ though I don't think we
disagree about the physics.

George

Date: 11 Oct 2006 14:21:35
From: Double-A
Subject: Re: infinite pill-shaped universe?

Brian Tung wrote:
> Double-A wrote:
> > Yup! Modern physics has consigned "relativistic mass" to the scrap
> > heap along with "aether".
>
> Relativistic mass may be how it is often presented in popular science--I
> did it myself a while ago--but it is ultimately confusing if you try to
> do any actual physics with it for long, and I don't use it anymore. I
> don't mention it in my Sky and Telescope article on relativistic travel,
> for instance. Instead, I refer to the object's momentum (in the
> direction of travel).

In NOVA's presentation "Einstein's Big Idea" of ober 11, 2005, they
say:

"NARRATOR: In Einstein's new world, the one true constant was not time
or even space, but light.

But Einstein's miracle year was not over; in one last great 1905 paper,
he would propose an even deeper unity. As he computed all the
implications of his new theory he noticed another strange connection,
this one between energy, mass and light.

DAVID BODANIS: Einstein realizes that the speed of light is kind of
like a cosmic speed limit, nothing can go faster. So imagine we have a
train charging along. And let's say it's getting up to the speed of
light, and we're stuffing more and more energy in trying to get it to
go faster and faster, but it's still bumping up against the speed of
light. So all this energy, where does it go? It has to go somewhere.
Amazingly it goes into the object's mass. From our point of view, the
train actually gets heavier. The energy becomes mass. It's an
incredible idea. Even Einstein is amazed by it.

ALBERT EINSTEIN: Look. I think I have found a connection between energy
and mass. If I am right then energy and mass are not absolute. They are
not distinct. They can be converted into one another. Energy can become
mass, and mass can become energy, and not just energy equaling mass.
Energy equals mass times the square of the speed of light."

My reading of this dramatization is that Einstein got his idea that
energy and mass were equivalent from the idea of energy converting into
relativistic mass. Was this an inaccurate portrayal? Or was
Einstein's "Big Idea" based on a faulty assumption? Is Einstein's "Big
Idea" beginning to crumble along with the demise of relativistic mass?

Double-A

> As for the aether, it is not a useful model for any phenomenon we have
> to deal with at the current time. That's not to say that will never
> happen, but if and when it does, it will not necessarily resemble the
> aether theory of the 19th century any more than our atomic theory
> resembles that of the ancient Greeks. In the meantime, it is merely a
> discredited theory.
>
> --
> Brian Tung <brian@isi.edu>
> The Astronomy Corner at http://astro.isi.edu/
> Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
> The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
> My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 11 Oct 2006 15:14:45
From: Brian Tung
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
> My reading of this dramatization is that Einstein got his idea that
> energy and mass were equivalent from the idea of energy converting into
> relativistic mass. Was this an inaccurate portrayal? Or was
> Einstein's "Big Idea" based on a faulty assumption? Is Einstein's "Big
> Idea" beginning to crumble along with the demise of relativistic mass?

You have to make a distinction between what the historical use of the
term was, and what its modern use is. The fact that Einstein made use
of relativistic mass does not obscure the second fact that it is a
confusing way to think about relativity. I don't think that Einstein
would disagree with that (although of course I don't know for sure).

In other words, it is not that the idea of relativistic mass is *wrong*.
It can, however, lead you to make improper conclusions about what will
happen in such and such a situation, not because the concept is wrong,
but because it gives you a mistaken intuition. In many of these cases,
you would be better off (in terms of arriving at the correct result)
with no intuition at all, than to have a mistaken intuition. Einstein
wasn't hampered by this, but then, he was a physicist by training.
Plus, it was his theory.

As such, I would not have corrected the poster who said that mass
increases without bound as velocity increases (or at most, I would have
said that it was anachronistic). No physicist could fail to know what
was meant, and it wasn't as though it led to any inappropriate
conclusions. It is merely discordant with modern usage of the term
"mass." It's a semantic issue, not a physical one.

This is not the only way that modern treatment of relativity differs
from Einstein's original formulation. His original formulation of
general relativity, for instance, was quite tied to the three dimensions
of space (x, y, and z) and time (t). The modern formulation is really
coordinate-free, preferring instead to deal with transformations in the
abstract. Eventually, to compute results, you will have to put the
coordinates in at the end. However, waiting until the end to do it
permits physicists great expressive power and generality, and it also
makes derivations ultimately easier to follow (though perhaps somewhat
harder to visualize).

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 11 Oct 2006 12:24:42
From: Double-A
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160590946.125364.61000@b28g2000cwb.googlegroups.com...
> > Mass is not an invariant quantity, it changes with relative speed.
> > That's what the special and general theory of relativity is all about.
> >
> > The mass of a particle at rest can be invariant. But the mass of a
> > particle in motion changes with its speed. You can see this with
> > electrons in a vacuum tube flying through a magnetic field. This is a
> > typical experiment (or was) that is done in college level physics
> > classes.
> >
> > You have a vacuum tube with an electron gun at one end and a phosphor
> > screen at another. You can change the voltage of the electron gun, and
> > thus, change the velocity of the electrons flying out of the end of the
> > gun. A spot of light glows at the point on the phosphor screen where
> > the electrons strike the phosphor. You can then apply a magnetic field
> > to the electron beam and cause the electrons to be accelerated through
> > an angle, shifting the location of the glowing spot.
> >
> > This is a cool apparatus because you can learn so much about things
> > with it. Knowing a few principles of geometry and electrostatics and
> > electrodynamics, you can weigh electrons, measure their speed and so
> > forth.
> >
> > You can vary the speed of the electrons from about 1% the speed of
> > light to about 90% the speed of light by changing the voltage of the
> > gun from 1,000V to about 100,000V.
> >
> > Once you do a few of these introductory experiments, you can then crank
> > up the voltage and deflect the beam of very high speed electrons and
> > measure their mass at speed. When you do this you see experimental
> > proof that Lorentz effects are real. That is, the mass of a moving
> > electron is far greater than a stationary electron.
> >
> > Now at this point in the course you see an old NSF film that shows that
> > mu-mesons produced by cosmic rays high in the Earth's atmosphere
> > wouldn't make it to the ground unless time to were distorted as
> > described in the Lorentz equations. The coup'd grace is an experiment
> > done in lecture that actually measures mu-mesons coursing through the
> > lecture hall from cosmic space! oooooo...
> >
> > It makes all this bs that people argue endlessly about here stand out
> > for what it is! lol.
>
> Everything you say about the experiments is true and yes
> the effects are real, but in the modern approach mass is
> treated as invariant and the gamma function is treated as
> part of the relation between mass, speed and energy. The
> concept of "relativistic mass" which you describe is
> nowadays seen as being anachronistic even if still useful
> in practical terms.
>
> George

Yup! Modern physics has consigned "relativistic mass" to the scrap
heap along with "aether".

But both terms refuse to die!

Double-A

Date: 11 Oct 2006 12:24:49
From: Brian Tung
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
> Yup! Modern physics has consigned "relativistic mass" to the scrap
> heap along with "aether".

Relativistic mass may be how it is often presented in popular science--I
did it myself a while ago--but it is ultimately confusing if you try to
do any actual physics with it for long, and I don't use it anymore. I
don't mention it in my Sky and Telescope article on relativistic travel,
for instance. Instead, I refer to the object's momentum (in the
direction of travel).

As for the aether, it is not a useful model for any phenomenon we have
to deal with at the current time. That's not to say that will never
happen, but if and when it does, it will not necessarily resemble the
aether theory of the 19th century any more than our atomic theory
resembles that of the ancient Greeks. In the meantime, it is merely a
discredited theory.

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 11 Oct 2006 12:21:30
From: dlzc
Subject: Re: infinite pill-shaped universe?

Dear William.Mook:

William.Mook@gmail.com wrote:
> Mass is not an invariant quantity, it changes with relative
> speed. That's what the special and general theory of
> relativity is all about.

Actually, no, sir, those theories are about energy (variable with
relative speed) and mass (invariant by definition).

> The mass of a particle at rest can be invariant. But the
> mass of a particle in motion changes with its speed. You
> can see this with electrons in a vacuum tube flying through
> a magnetic field. This is a typical experiment (or was) that
> is done in college level physicsclasses.

Yes sir, I understand what you are saying. However, *by standard
definition* in physics, mass is invariant, namely
mass = rest mass = inertial mass = gravitational mass
mass =/= relativistic mass (except with v = 0)
(Note that if the equivalence principle is proven false, the
equivalence of inertial and gravitational mass is invalidated.)

> You have a vacuum tube with an electron gun at one end
> and a phosphor screen at another. You can change the
> voltage of the electron gun, and thus, change the velocity of
> the electrons flying out of the end of the gun. A spot of light
> glows at the point on the phosphor screen where the
> electrons strike the phosphor. You can then apply a
> magnetic field to the electron beam and cause the electrons
> to be accelerated through an angle, shifting the location of the
> glowing spot.
>
> This is a cool apparatus because you can learn so much
> about things with it. Knowing a few principles of geometry
> and electrostatics and electrodynamics, you can weigh
> electrons, measure their speed and so forth.
>
> You can vary the speed of the electrons from about 1% the
> speed of light to about 90% the speed of light by changing
> the voltage of the gun from 1,000V to about 100,000V.
>
> Once you do a few of these introductory experiments, you
> can then crank up the voltage and deflect the beam of very
> high speed electrons and measure their mass at speed. When
> you do this you see experimental proof that Lorentz effects are
> real. That is, the mass of a moving electron is far greater than
> a stationary electron.

Note that if you introduce a magnetic field, to accelerate the electron
stream transverse to the entering path, you find that the acceleration
is a function of invariant mass (or just mass), and not relativistic
mass. Relativistic mass has an increasingly obnoxious component, the
vector contribution, that only comes into play "directly" if you stick
to 1D problems. When you move on to more complex issues, relativistic
mass becomes a monkey on your back.

> Now at this point in the course you see an old NSF film that
> shows that mu-mesons produced by cosmic rays high in the
> Earth's atmosphere wouldn't make it to the ground unless time to
> were distorted as described in the Lorentz equations. The coup'd
> grace is an experiment done in lecture that actually measures
> mu-mesons coursing through the lecture hall from cosmic space!
> oooooo...

Yes sir. Even repeated at high altitude, so that the flux of said
mu-mesons (muons) can be shown to decay unsurprisingly (in relativity,
but death for so many other "alternative models").

> It makes all this bs that people argue endlessly about here stand
> out for what it is! lol.

It isn't bs. It is convention. It makes sense to find some
invariants, and hold them so... when it makes sense to do so. In this
case, it makes sense to do so.

I provided links before, and I can provide them again, at need. I am
not lying, I am not slanting the truth. It is accepted terminology in
the scientific community to use mass as I have presented it... separate
from relativistic mass.

Thank you for your quick response. I was not trying to put words in
your mouth by mentioning your name. I do not expect to have convinced
you either.

David A. Smith

Date: 11 Oct 2006 11:22:26
From:
Subject: Re: infinite pill-shaped universe?

Mass is not an invariant quantity, it changes with relative speed.
That's what the special and general theory of relativity is all about.

The mass of a particle at rest can be invariant. But the mass of a
particle in motion changes with its speed. You can see this with
electrons in a vacuum tube flying through a magnetic field. This is a
typical experiment (or was) that is done in college level physics
classes.

You have a vacuum tube with an electron gun at one end and a phosphor
screen at another. You can change the voltage of the electron gun, and
thus, change the velocity of the electrons flying out of the end of the
gun. A spot of light glows at the point on the phosphor screen where
the electrons strike the phosphor. You can then apply a magnetic field
to the electron beam and cause the electrons to be accelerated through
an angle, shifting the location of the glowing spot.

This is a cool apparatus because you can learn so much about things
with it. Knowing a few principles of geometry and electrostatics and
electrodynamics, you can weigh electrons, measure their speed and so
forth.

You can vary the speed of the electrons from about 1% the speed of
light to about 90% the speed of light by changing the voltage of the
gun from 1,000V to about 100,000V.

Once you do a few of these introductory experiments, you can then crank
up the voltage and deflect the beam of very high speed electrons and
measure their mass at speed. When you do this you see experimental
proof that Lorentz effects are real. That is, the mass of a moving
electron is far greater than a stationary electron.

Now at this point in the course you see an old NSF film that shows that
mu-mesons produced by cosmic rays high in the Earth's atmosphere
wouldn't make it to the ground unless time to were distorted as
described in the Lorentz equations. The coup'd grace is an experiment
done in lecture that actually measures mu-mesons coursing through the
lecture hall from cosmic space! oooooo...

It makes all this bs that people argue endlessly about here stand out
for what it is! lol.

Cheers

William

Date: 11 Oct 2006 20:19:26
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1160590946.125364.61000@b28g2000cwb.googlegroups.com...
> Mass is not an invariant quantity, it changes with relative speed.
> That's what the special and general theory of relativity is all about.
>
> The mass of a particle at rest can be invariant. But the mass of a
> particle in motion changes with its speed. You can see this with
> electrons in a vacuum tube flying through a magnetic field. This is a
> typical experiment (or was) that is done in college level physics
> classes.
>
> You have a vacuum tube with an electron gun at one end and a phosphor
> screen at another. You can change the voltage of the electron gun, and
> thus, change the velocity of the electrons flying out of the end of the
> gun. A spot of light glows at the point on the phosphor screen where
> the electrons strike the phosphor. You can then apply a magnetic field
> to the electron beam and cause the electrons to be accelerated through
> an angle, shifting the location of the glowing spot.
>
> This is a cool apparatus because you can learn so much about things
> with it. Knowing a few principles of geometry and electrostatics and
> electrodynamics, you can weigh electrons, measure their speed and so
> forth.
>
> You can vary the speed of the electrons from about 1% the speed of
> light to about 90% the speed of light by changing the voltage of the
> gun from 1,000V to about 100,000V.
>
> Once you do a few of these introductory experiments, you can then crank
> up the voltage and deflect the beam of very high speed electrons and
> measure their mass at speed. When you do this you see experimental
> proof that Lorentz effects are real. That is, the mass of a moving
> electron is far greater than a stationary electron.
>
> Now at this point in the course you see an old NSF film that shows that
> mu-mesons produced by cosmic rays high in the Earth's atmosphere
> wouldn't make it to the ground unless time to were distorted as
> described in the Lorentz equations. The coup'd grace is an experiment
> done in lecture that actually measures mu-mesons coursing through the
> lecture hall from cosmic space! oooooo...
>
> It makes all this bs that people argue endlessly about here stand out
> for what it is! lol.

Everything you say about the experiments is true and yes
the effects are real, but in the modern approach mass is
treated as invariant and the gamma function is treated as
part of the relation between mass, speed and energy. The
concept of "relativistic mass" which you describe is
nowadays seen as being anachronistic even if still useful
in practical terms.

George

Date: 11 Oct 2006 19:29:25
From: Sorcerer
Subject: Re: infinite pill-shaped universe?

"George Dishman" <george@briar.demon.co.uk > wrote in message
news:egjf87$m57$1@news.freedom2surf.net...

Date: 26 Oct 2006 16:08:20
From:
Subject: Re: infinite pill-shaped universe?

Wow, George, you are an argumentative old cuss... hmm...

George Dishman wrote:
> William.Mook@gmail.com wrote:
> > George Dishman wrote:
> > > William.Mook@gmail.com wrote:
> > > > Momentum, mass, the galilean notion of relativity, the newtonian notion
> > > > of absolute time, - all those aspects of every-day science and
> > > > engineering, are hard-wired into our brains.
> > >
> > > I completely agree, but nature is not so limited
> >
> > I agree with this.
> >
> > > and
> > > our mathematical description of it should not be so
> > > constrained.
> >
> > Our mathematical description is NOT constrained, and I never said
> > anything about our mathematical description, so your point is moot.
>
> I didn't suggest you did, the point remains valid.

You are confused here. I never suggested we should constrain our
mathematical descriptions. I merely suggested that appealing to
intuitive notions of space and time add real depth to our understanding
of the mathematics.

> > > > You folks make absolute statements that are highly suspect, or plain
> > > > wrong, (as when I was told to try again by one poster at one point when
> > > > I merely said momentum was mass times velocity! haha.. )
> > >
> > > That was me, I assumed you knew the answer since
> > > you seemed familiar with SR.
> >
> > I am intimately familiar with special relativity among other things, so
> > your presumption that I am wrong is itself wrong! And your statement
> > was wrong in the context of my discussion anway.
>
> The context of the discussion is the use of invariant
> mass versus "relativistic mass" in SR.

As a means to tap into our intuitive understanding of things, yes. I
didn't suggest we stop there.

> > > The correct equation is:
> >
> > What is correct and what is not correct depends on the context of our
> > discussion. You presume our disagreement stems from my lack of
> > knowledge,
>
> I presume no such thing,

Whenever you say something like 'the correct equation is...' presumes
all other modes of understanding are somehow incorrect. You should
really avoid brow-beating students in this way. It silences their own
rich understanding by assuming they have nothing to contribute merely
because it doesn't follow the lesson plan.

> I believe our disagreement
> reflects a change in teaching practice over the last
> few decades

A agree. Some things have changed for the worse! lol.

> to get away from the old pseudo-
> Newtonian approach to a more fully relativistic
> treatment.

Hogwash. The new approaches merely seek to avoid the same tired old
questions because they're boring for teachers to handle year in and
year out. They're quite efficient to this end. But they have a cost,
and that cost is making relativity seem like a different field of
experience than the one they know intuitively - which isolates
understanding from experience - and which I judge to be a bad thing.

>
> > when in reality it stems from your lack of appreciation of
> > certain important details in your thought process about knowledge we
> > both share..
> >
> > > p = m [ v c / sqrt(c^2 - v^2) ]
> >
> > In the context of special relativity this equation has certain
> > important meaning. It might be said to be correct in certain contexts.
>
> Indeed, it is obviously only valid for massive objects
> and inappropriate for photons, but in the context of
> discussing "relativistic mass" it is correct.

Except that it avoids any connection with our intuitive understanding
of these things evidenced by for example, juggling.

> > In the low speed context with v << c the statement mass times velocity
> > is close enough to be said to be true.
>
> It is close enough to be a useable approximation of
> course,

Which is a starting point of richer understanding, not the end point.

> but our context was the use of "relativistic
> mass" which is specifically used where the
> approximation p ~ m v is not adequate.

Except as a starting point of making connections to the intuitive
knowledge that exists in all learners.

> > For example, if you set c=1 and v=1/1000000 then p = mv is true to one
> > part in 5 x 10^-15 If you had a gram of copper and wished to calculate
> > the momentum of a gram of the stuff moving at 300 m/sec the difference
> > between p=mv and the 'correct' SR formula the error would amount to 5 x
> > 10^-15 grams of material. Since the atomic weight of copper is 63.546
> > amu, this amounts to 47,367,261 atoms difference, which is
> > substantially correct in any realistic since. So, the Newtonian
> > equation is obviously an important equation since this is what our
> > brains are hardwired to know intuitively -
>
> Our brains are hardwired to know intuitively that
> momentum is a linear function of speed as v
> approaches c? I don't think so.

You are being obtuse.

Our hardwiring doesn't understand massive objects approaching c. Our
hardwiring does understand our experience of moving masses in a deep
way - as catching a softball or juggling attest to. It is connecting
to that experience that I am speaking of. Tapping into deeply known
things is the source of much knowledge - encoded in our beings by
evolution. I believe we lose something by changing curricula to avoid
such connections merely to make the jobs of teachers easier.

> > and by referencing this
> > equation in our discussion of relativity, our intuitive knowledge is
> > tapped to deepen and enrich our understanding of relativity.
> >
> >
> > > or mass multiplied by a slightly more complex function
> > > of speed.
> >
> > Yes, but its a moot point in the context of my earlier discussion as
> > I've already pointed out.
> >
> > > Of course you can group it like this
> > >
> > > p = [ m c / sqrt(c^2 - v^2) ] v
> > >
> > > and call the term in square brackets "relativistic mass"
> >
> > Yes, which allows you to make important connections to your intuitive
> > understanding of reality. This explains why it was done this way at the
> > outset in our history of learning about the universe.
> >
> > > but it is just a cludge to allow the old Newtonian equation
> > > to be used in a relativistic situation.
> >
> > If your goal is isolate your intellect from your intuition this is a
> > way to proceed. I prefer a more integrative approach since it provides
> > the basis of a richer understanding by tapping the into the depths of
> > what humans are. As I've already explained about 10x
>
> My goal was to ensure that the lurkers who may
> follow these conversations and aren't as familiar
> with SR as you are not misled into thinking that
> mass varies with speed

But that idea that mass varies with speed (or that time varies with
speed) can be a useful way of understanding what is going on at a deep
level by appealing to what things seem like (if not pushed too far) - I
see value in maintaining that connection you do not. You see only the
benefit in avoiding tired old questions that lead to deeper
understanding among learners when those questions are answered. They
may be tired for us, but not for them and that's the point.

> and are instead aware
> that the anachronistic "relativistic mass" is a
> composite term which includes the actual invariant
> mass and a speed-dependent term which is
> frequently associated with the mass in the real
> equations.

YES!

> You are welcome to use whatever
> approach you like of course.

Haha... good solid statement followed by pointless brow-beating! lol.
I knew it was too good to last! haha..

> George

Date: 26 Oct 2006 16:07:57
From:
Subject: Re: infinite pill-shaped universe?

Date: 27 Oct 2006 01:32:16
From: George Dishman
Subject: Re: infinite pill-shaped universe?

William.Mook@gmail.com wrote:
> Wow, George, you are an argumentative old cuss... hmm...

'Fraid so ;-)

However, let me remind you of your comment that
started all this. You wrote in message:
http://groups.google.co.uk/group/sci.astro/msg/5ab9a4a05fdf1593

> Mass is not an invariant quantity, it changes with relative speed.
> That's what the special and general theory of relativity is all about.
>
> The mass of a particle at rest can be invariant. But the mass of a
> particle in motion changes with its speed. You can see this with
> electrons in a vacuum tube ...

Mass varying with speed is most definitely not "what
the special and general theory of relativity is all about."
nor IMO is it a good way to start learning what SR or
GR are really about.

> George Dishman wrote:
> > William.Mook@gmail.com wrote:
> > > George Dishman wrote:
> > > > William.Mook@gmail.com wrote:
> > > > > Momentum, mass, the galilean notion of relativity, the newtonian notion
> > > > > of absolute time, - all those aspects of every-day science and
> > > > > engineering, are hard-wired into our brains.
> > > >
> > > > I completely agree, but nature is not so limited
> > >
> > > I agree with this.
> > >
> > > > and
> > > > our mathematical description of it should not be so
> > > > constrained.
> > >
> > > Our mathematical description is NOT constrained, and I never said
> > > anything about our mathematical description, so your point is moot.
> >
> > I didn't suggest you did, the point remains valid.
>
> You are confused here. I never suggested we should constrain our
> mathematical descriptions.

I know, and I didn't say you did, so now who's being
argumentative? If you want to push the point, what I
was saying is that, for example, we shouldn't cast
our equation for momentum is this form:

p = m_r * v

from which we must have

m_r = m c / sqrt(c^2 - v^2)

only to be compliant with everday experience. Much of
modern science (and all of QM!) is counter-intuitive and
students will at some point need to break that connection.
It is my feeling that writing the equation in this form:

p = m [ v c / sqrt(c^2 - v^2) ]

makes it much clearer that mass is an invariant scalar.

> I merely suggested that appealing to
> intuitive notions of space and time add real depth to our understanding
> of the mathematics.

I, on the other hand, think it unnecessarily creates a
misunderstanding, the idea that mass varies with speed.

> > > > > You folks make absolute statements that are highly suspect, or plain
> > > > > wrong, (as when I was told to try again by one poster at one point when
> > > > > I merely said momentum was mass times velocity! haha.. )
> > > >
> > > > That was me, I assumed you knew the answer since
> > > > you seemed familiar with SR.
> > >
> > > I am intimately familiar with special relativity among other things, so
> > > your presumption that I am wrong is itself wrong! And your statement
> > > was wrong in the context of my discussion anway.
> >
> > The context of the discussion is the use of invariant
> > mass versus "relativistic mass" in SR.
>
> As a means to tap into our intuitive understanding of things, yes. I
> didn't suggest we stop there.

No, you simply said that I was wrong when I said
the following in message
http://groups.google.co.uk/group/sci.astro/msg/8307e0dedb0e2f49

>> The FAQ:
>>
>> http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
>>
>> Scientifically speaking, mass is invariant.

Again, consider what you said of that:

> Mass is not an invariant quantity, it changes with relative speed.
> That's what the special and general theory of relativity is all about.
>
> The mass of a particle at rest can be invariant. But the mass of a
> particle in motion changes with its speed. ...

> > > > The correct equation is:
> > >
> > > What is correct and what is not correct depends on the context of our
> > > discussion. You presume our disagreement stems from my lack of
> > > knowledge,
> >
> > I presume no such thing,
>
> Whenever you say something like 'the correct equation is...' presumes
> all other modes of understanding are somehow incorrect.

No, it meant that one equation:

p = m [ v c / sqrt(c^2 - v^2) ]

is accurate to the best of current scientific knowledge while the

p = m v

is only an approximation. It may be a very useful approximation
but we shouldn't give lurkers the idea that it can be used on all
occasions.

> You should
> really avoid brow-beating students in this way. It silences their own
> rich understanding by assuming they have nothing to contribute merely
> because it doesn't follow the lesson plan.

I am against giving students incorrect information. Starting
by showing

p = m [ v c / sqrt(c^2 - v^2) ]

and then go on to discuss the situations where p = mv
is a valid approximation is IMO much more informative
and aids the understaing of when use of approximations
in general is appropriate.

> > I believe our disagreement
> > reflects a change in teaching practice over the last
> > few decades
>
> A agree. Some things have changed for the worse! lol.

YMMV ;-)

> > to get away from the old pseudo-
> > Newtonian approach to a more fully relativistic
> > treatment.
>
> Hogwash. The new approaches merely seek to avoid the same tired old
> questions because they're boring for teachers to handle year in and
> year out. They're quite efficient to this end. But they have a cost,
> and that cost is making relativity seem like a different field of
> experience than the one they know intuitively - which isolates
> understanding from experience - and which I judge to be a bad thing.

I on the other hand think it gets them into thinking in
a 4D way which is essential as they move into GR.

> > > when in reality it stems from your lack of appreciation of
> > > certain important details in your thought process about knowledge we
> > > both share..
> > >
> > > > p = m [ v c / sqrt(c^2 - v^2) ]
> > >
> > > In the context of special relativity this equation has certain
> > > important meaning. It might be said to be correct in certain contexts.
> >
> > Indeed, it is obviously only valid for massive objects
> > and inappropriate for photons, but in the context of
> > discussing "relativistic mass" it is correct.
>
> Except that it avoids any connection with our intuitive understanding
> of these things evidenced by for example, juggling.

If you want to be a juggler use Newton. If you want to
work in high-energy physics or cosmology or any other
field where SR and GR matter then you need to start
think in 4D.

> > > In the low speed context with v << c the statement mass times velocity
> > > is close enough to be said to be true.
> >
> > It is close enough to be a useable approximation of
> > course,
>
> Which is a starting point of richer understanding, not the end point.

I disagree, IMO, it avoids understanding the true behaviour
of nature by coating it in a veneer of Newtonian thinking.

> > but our context was the use of "relativistic
> > mass" which is specifically used where the
> > approximation p ~ m v is not adequate.
>
> Except as a starting point of making connections to the intuitive
> knowledge that exists in all learners.

No, you simply said my statement

>> Scientifically speaking, mass is invariant.

was wrong. In fact at the ed of your post you
implied it was "bs".

> > > For example, if you set c=1 and v=1/1000000 then p = mv is true to one
> > > part in 5 x 10^-15 If you had a gram of copper and wished to calculate
> > > the momentum of a gram of the stuff moving at 300 m/sec the difference
> > > between p=mv and the 'correct' SR formula the error would amount to 5 x
> > > 10^-15 grams of material. Since the atomic weight of copper is 63.546
> > > amu, this amounts to 47,367,261 atoms difference, which is
> > > substantially correct in any realistic since. So, the Newtonian
> > > equation is obviously an important equation since this is what our
> > > brains are hardwired to know intuitively -
> >
> > Our brains are hardwired to know intuitively that
> > momentum is a linear function of speed as v
> > approaches c? I don't think so.
>
> You are being obtuse.

It's what you seemed to be saying.

> Our hardwiring doesn't understand massive objects approaching c. Our
> hardwiring does understand our experience of moving masses in a deep
> way - as catching a softball or juggling attest to. It is connecting
> to that experience that I am speaking of. Tapping into deeply known
> things is the source of much knowledge - encoded in our beings by
> evolution. I believe we lose something by changing curricula to avoid
> such connections merely to make the jobs of teachers easier.

Whereas I believe we gain a deeper understanding by using
our ability to visualise 3D to see how the 4D universe works
by visualise worldlines and spacetime using an x,y,t view.
The aim isn't to make the teacher's job easier but to give
the students the tools they will need in their careers.

> > > If your goal is isolate your intellect from your intuition this is a
> > > way to proceed. I prefer a more integrative approach since it provides
> > > the basis of a richer understanding by tapping the into the depths of
> > > what humans are. As I've already explained about 10x
> >
> > My goal was to ensure that the lurkers who may
> > follow these conversations and aren't as familiar
> > with SR as you are not misled into thinking that
> > mass varies with speed
>
> But that idea that mass varies with speed (or that time varies with
> speed) can be a useful way of understanding what is going on at a deep
> level ..

At the deeper level, mass does _not_ change with
speed, it is invariant. It only _appears_ to change when
you assume for example that p = m v and then calculate
m as p/v. That is the whole point, you are advocating
teaching a concept that subsequently students will have
to discard.

> by appealing to what things seem like (if not pushed too far) - I
> see value in maintaining that connection you do not. You see only the
> benefit in avoiding tired old questions that lead to deeper
> understanding among learners when those questions are answered. They
> may be tired for us, but not for them and that's the point.

No, I have no problem with the questions, it is teaching
erroneous concepts to make life easier for the teacher
that I am objecting to.

> > and are instead aware
> > that the anachronistic "relativistic mass" is a
> > composite term which includes the actual invariant
> > mass and a speed-dependent term which is
> > frequently associated with the mass in the real
> > equations.
>
> YES!
>
> > You are welcome to use whatever
> > approach you like of course.
>
> Haha... good solid statement followed by pointless brow-beating! lol.
> I knew it was too good to last! haha..

Not "brow-beating" at all, I was merely acknowledging that
once while one may understand the deeper aspects, it is
perfectly reasonable and pragmatically very appropriate
to use the old "relativistic mass" approach in getting
numbers out of the theory.

George

Date: 11 Oct 2006 10:47:16
From: dlzc
Subject: Re: infinite pill-shaped universe?

Dear stapleton:

stapleton wrote:
> "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com> wrote in
> message news:O_ZWg.3210$v43.2775@fed1read02...
> > Dear stapleton:
> >
> > "stapleton" <alier342@silverman.com> wrote in message
> > news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
> >>
> >> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
> >> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
> >>> stapleton wrote:
> >>>>
> >>>> I think its beyond our ability to understand in human
> >>>> terms. Time and space do not exist outside of the
> >>>> "expanding universe".
> >>>
> >>> Excuse me but if "its beyond our ability to understand
> >>> in human terms" then it is NOT SCIENCE but religion.
> >>
> >> There are ALOT of things in science that are not
> >> understandable in human terms.
> >> Take a class in quantum mechanics. You see crazy
> >> formulas like: time * space = mass * energy * Si
> >> (Si is a constant)
> >>
> >> There are even more thinks in science that are hard to
> >> comprehend.
> >>
> >> Such as general relativity theory.
> >> As an object approaches the speed of light, its mass
> >
> > ... *energy*, not mass ...
>
> http://einstein.stanford.edu/content/relativity/q389.html
> Experimentally, the increase of mass with velocity has
> been confirmed to great precision...

http://en.wikipedia.org/wiki/Rest_mass
http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
http://sciastro.astronomy.net/sci.astro.4.FAQ
... down about 3/4 of the page to the thread by William H. Mook, Jr.
titled "What are tachyons? Are they real?". He is describing
"relativistic mass" as separate from mass (an invariant quantity).

In case you don't bother to research the links, the correct formula for
the energy of a particle/body is:
E^2 = (pc)^2 + (mc^2)^2

This moves the component that is a vector to a single location...
momentum. You are thinking "relativistic mass", which is a Rube
Goldberg nightmare of vector and scalar components. Just so "we" can
only remember "E=mc^2", where m (in this nonstandard case) is
"relativistic mass".

I don't expect to convince you, but for the record, mass is an
invariant quantity in current usage. And to correct yet another
nonstandard usage:
> Experimentally, the increase of [energy] with velocity has
> been confirmed to great precision...

I'm really not trying to start a flame war, or to bust your chops
here... OK? That is why I tried to agree with you in the points you
made.

David A. Smith

Date: 12 Oct 2006 00:54:22
From: stapleton
Subject: Re: infinite pill-shaped universe?

"dlzc" <dlzc1@cox.net > wrote in message
news:1160588835.971331.300450@k70g2000cwa.googlegroups.com...
> Dear stapleton:
>
> stapleton wrote:
>> "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com> wrote in
>> message news:O_ZWg.3210$v43.2775@fed1read02...
>> > Dear stapleton:
>> >
>> > "stapleton" <alier342@silverman.com> wrote in message
>> > news:TEXWg.10650$vJ2.7810@newssvr12.news.prodigy.com...
>> >>
>> >> "jacob navia" <jacob@jacob.remcomp.fr> wrote in message
>> >> news:452bc9e5$0$5097$ba4acef3@news.orange.fr...
>> >>> stapleton wrote:
>> >>>>
>> >>>> I think its beyond our ability to understand in human
>> >>>> terms. Time and space do not exist outside of the
>> >>>> "expanding universe".
>> >>>
>> >>> Excuse me but if "its beyond our ability to understand
>> >>> in human terms" then it is NOT SCIENCE but religion.
>> >>
>> >> There are ALOT of things in science that are not
>> >> understandable in human terms.
>> >> Take a class in quantum mechanics. You see crazy
>> >> formulas like: time * space = mass * energy * Si
>> >> (Si is a constant)
>> >>
>> >> There are even more thinks in science that are hard to
>> >> comprehend.
>> >>
>> >> Such as general relativity theory.
>> >> As an object approaches the speed of light, its mass
>> >
>> > ... *energy*, not mass ...
>>
>> http://einstein.stanford.edu/content/relativity/q389.html
>> Experimentally, the increase of mass with velocity has
>> been confirmed to great precision...
>
> http://en.wikipedia.org/wiki/Rest_mass
> http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
> http://sciastro.astronomy.net/sci.astro.4.FAQ
> ... down about 3/4 of the page to the thread by William H. Mook, Jr.
> titled "What are tachyons? Are they real?". He is describing
> "relativistic mass" as separate from mass (an invariant quantity).
>
> I don't expect to convince you, but for the record, mass is an
> invariant quantity in current usage. And to correct yet another
> nonstandard usage:
>> Experimentally, the increase of [energy] with velocity has
>> been confirmed to great precision...
>
> I'm really not trying to start a flame war, or to bust your chops
> here... OK? That is why I tried to agree with you in the points you
> made.
>
> David A. Smith

I'll admit to be a pedestrian on the subject.
Interesting links. You learn something new everyday. :-)

Date: 11 Oct 2006 18:16:09
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear stapleton:

"stapleton" <alier342@silverman.com > wrote in message
news:2ngXg.9496$TV3.5177@newssvr21.news.prodigy.com...
...
> I'll admit to be a pedestrian on the subject.
> Interesting links. You learn something new everyday. :-)

And thank God for that. It is about the only reason to hang
around...

David A. Smith

Date: 12 Oct 2006 09:13:58
From: dlzc
Subject: Re: infinite pill-shaped universe?

Dear William Mook:

Since this is "tempest in a teapot"...

William.Mook@gmail.com wrote:
> N:dlzc D:aol T:com (dlzc) wrote:
> > Dear William.Mook:
> >
> > <William.Mook@gmail.com> wrote in message
...
> > Baez says mass is rest mass:
> > http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
>
> Hold on now skippy, Baez says this at the outset;
>
> "There is sometimes confusion surrounding the subject of mass in
> relativity. This is because there are two separate uses of the term.
> Sometimes people say "mass" when they mean "relativistic mass",
> mr but at other times they say "mass" when they mean
> "invariant mass","
>
> Which pretty much is what I'm saying. So, what's your point?

You have been circumspect in your writings, up until this thread, when
you claim that "mass" is always "relativistic mass":
http://groups.google.com/group/sci.astro.amateur/msg/5ab9a4a05fdf1593
http://groups.google.com/group/sci.astro.amateur/msg/8fff4b22e91d0786

> > Hillman says mass is rest mass:
> > http://groups.google.com/group/sci.physics/msg/6f1f1b991a0e6c26
>
>
> Hillman quotes Taylor and Wheeler, but not before saying this;
>
> expunge everything you've ever read about "relativistic mass" from your
> memory; think rather in terms of "relativistic kinetic energy" and your
> life in physics will be much easier
>
> Which again pretty much supports what I've said.

Up until you claim that "mass" is "relativistic mass", you have not
said anything wrong. Even that is not wrong, but it is an archaic use.

> > Taylor and Wheeler say mass is rest mass:
> > "Spacetime Physics"
>
> ??? Wheeler had an argument with the publisher over putting
> his name on this elementary text BECAUSE of its use of
> relativistic mass!!! It was only when he was allowed to say
> derogatory things about the use of the term that he put his
> name on it!
>
> Explaining that there is a difference between rest mass which
> is an invariant and relativistic mass to a popular audience
> interested in relativity is pretty much what all these authors have
> done - in much the same way I have done it.

"Pretty much" is not "the same".

> > Gary Oas says mass is rest mass:
> > http://adsabs.harvard.edu/abs/2005physics...4110O
> >
> > ... and here
> > http://arxiv.org/abs/physics/0504110
>
> But the Harvard physicist DEFINES mass as rest mass
> eschewing all other discussions of mass as being
> nonsensical only AFTER saying that relativistic mass is,
> "a heuristic device a preliminary study of first time learners"
> in both papers.
>
> Which pretty much supports what I was saying to the
> usenet group here.

Not at all. You claim that mass = relativistic mass, regardless of
context or intent. At least in *this* thread.

> > ... a mixed bag on this site...
> > http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html#mas
> > ... with lots of disclaimers.
> >
> > Your usage is non standard, you will get in trouble if you try
> > and use formulae based on mass = rest mass.
>
> Never did that. I did say invariant mass IS rest mass! lol.
> Which is PRECISELY what YOU are spouting here.
>
> Perhaps you should include on your reading list,
>
> "In defense of relativistic mass," by T. R. Sandin, Am. J. Phys. 59,
> 1032 (1991)

Why does your electron stream not accelerate transverse to its path
(via a magnetic field) based on its relativistic mass? How is it that
mass, a scalar, has vector behavior? Momentum has the expectation of
carrying vector information... why not leave it there?

> > And exclamations of
> > "bullshit" are unconvincing.
>
> I didn't use the term sir, but be warned, if you spout bullshit,
> it will be called such! lol.

http://groups.google.com/group/sci.astro.amateur/msg/f236715765b3ffe2
... perhaps someone spoofed your header here?

> > And hints that everyone else
> > doesn't understand special relativity should give you a clue.
>
> Never said that either, that's all in YOUR head! and I'm not
> responsible for it! lol..

http://groups.google.com/group/sci.astro.amateur/msg/8fff4b22e91d0786
<QUOTE >
Sorry, you really don't understand the special theory of relativity if
you do not
get this.
<END QUOTE >
"This" being "mass is relativistic mass".

That isn't the only example. It isn't in my head, but in your words.

> > Believe what you will. I just wish you didn't spread
> > antiquated usage around like it was gospel.
>
> You're the one who's offended by my total lack of respect for
> Wheeler's gospel mass IS rest mass! lol.

My offense isn't at most of what you say, William. I did provide a
reference to your very words, remember? As to offense, why is it that
"path-transverse mass" isn't the same as "path-parallel mass" when
using "relativistic mass"? If your concern is not to confuse "the
masses", how can you support such a double standard?

> David, this whole discussion makes it seem that mass is
> such an important quantity. Actually what we should be
> talking about is momentum current along the world line in
> 4 space of an object. But that's so far removed from what
> the original point of discussion was introducing it then
> would just be lording one's knowledge over others for no real
> purpose.

You are "lording over" your particular choice of definition of terms,
and "denigrating" anyone that doesn't use it. Your hands appear soiled
too.

Do we speak the same words with different meanings (pure chaos, where
"the masses" live), do we qualify everything we say (safest), or do we
codify the English language (pushing all creativity out of it).

My agenda is to inform where the physics community is going. I
understand that you know the history, and don't seem to care where it
is going. So what is your agenda? When will you (next) write a
physics text?

Your words can be the last.

Date: 12 Oct 2006 06:10:15
From:
Subject: Re: infinite pill-shaped universe?

N:dlzc D:aol T:com (dlzc) wrote:
> Dear William.Mook:
>
> <William.Mook@gmail.com> wrote in message
> news:1160623819.805199.226900@c28g2000cwb.googlegroups.com...
> > rest mass is an invariant. mass is not since it varies
> > with speed.
>
> Mass does not vary with speed. Mass is not a vector, yet
> relativistic mass does not correctly describe how a charge
> accelerates in a magnetic field.
>
> No *current* physics textbook uses mass for anything except rest
> mass.

By definition yes. Because there is confusion between rest mass and so
called relativistic mass. In every day non-technical usage (such as
found on usenet!) one must be careful to delineate their usage so as to
add to the enlightenment of humanity, not its confusion - no matter how
mad specialists get! lol.

>
> Baez says mass is rest mass:
> http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html

Hold on now skippy, Baez says this at the outset;

"There is sometimes confusion surrounding the subject of mass in
relativity. This is because there are two separate uses of the term.
Sometimes people say "mass" when they mean "relativistic mass", mr but
at other times they say "mass" when they mean "invariant mass","

Which pretty much is what I'm saying. So, what's your point?

> Hillman says mass is rest mass:
> http://groups.google.com/group/sci.physics/msg/6f1f1b991a0e6c26

Hillman quotes Taylor and Wheeler, but not before saying this;

expunge everything you've ever read about "relativistic mass" from your
memory; think rather in terms of "relativistic kinetic energy" and your
life in physics will be much easier

Which again pretty much supports what I've said.

> Taylor and Wheeler say mass is rest mass:
> "Spacetime Physics"

??? Wheeler had an argument with the publisher over putting his name
on this elementary text BECAUSE of its use of relativistic mass!!! It
was only when he was allowed to say derogatory things about the use of
the term that he put his name on it!

Explaining that there is a difference between rest mass which is an
invariant and relativistic mass to a popular audience interested in
relativity is pretty much what all these authors have done - in much
the same way I have done it.

> Gary Oas says mass is rest mass:
> http://adsabs.harvard.edu/abs/2005physics...4110O
>
> ... and here
> http://arxiv.org/abs/physics/0504110

But the Harvard physicist DEFINES mass as rest mass eschewing all other
discussions of mass as being nonsensical only AFTER saying that
relativistic mass is, "a heuristic device a preliminary study of first
time learners" in both papers.

Which pretty much supports what I was saying to the usenet group here.

> ... a mixed bag on this site...
> http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html#mas
> ... with lots of disclaimers.
>
> Your usage is non standard, you will get in trouble if you try
> and use formulae based on mass = rest mass.

Never did that. I did say invariant mass IS rest mass! lol. Which is
PRECISELY what YOU are spouting here.

Perhaps you should include on your reading list,

"In defense of relativistic mass," by T. R. Sandin, Am. J. Phys. 59,
1032 (1991)

> And exclamations of
> "bullshit" are unconvincing.

I didn't use the term sir, but be warned, if you spout bullshit, it
will be called such! lol.

> And hints that everyone else
> doesn't understand special relativity should give you a clue.

Never said that either, that's all in YOUR head! and I'm not
responsible for it! lol..
>
> Believe what you will. I just wish you didn't spread antiquated
> usage around like it was gospel.

You're the one who's offended by my total lack of respect for Wheeler's
gospel mass IS rest mass! lol.

>
> David A. Smith

David, this whole discussion makes it seem that mass is such an
important quantity. Actually what we should be talking about is
momentum current along the world line in 4 space of an object. But
that's so far removed from what the original point of discussion was
introducing it then would just be lording one's knowledge over others
for no real purpose.

Cheers

Date: 12 Oct 2006 05:43:36
From:
Subject: Re: infinite pill-shaped universe?

George,

I read the damned article before I posted it! Why the hell do you
think I posted it? lol. I think we're arguing over nothing!

To put it a little more technically, the mass 'current' in 4 space is
the invariant because the interval along s is treated as an invariant
in 4 space. Speed in 4 space along s (the length of the world line
describing the position of the particle in 4 space) is an invariant.

The problem with all that is that folks reading that sentence here
won't understand a lick of it. They might start to understand it when
they consider that a given mass sitting at rest next to them is flying
through 4-space in the time direction at the speed of light, along with
them! So, time is maximal and mass is minimal.

When the object moves relative to them in 3 space the direction of the
object's flux in 4 space rotates, its speed doesn't change at all along
its path, merely the projection of its speed into 3 space changes. The
conception of this as a rotation is further bolstered by looking at the
Lorentz transformation (LT) formula or 'gamma' itself! and simple
rotational geometry

Here's the formula for a circle with a radius of 1

1 = x^2 + y^2

the projection of the radius on to one of the axes in terms of the
other axis can be written as;

x = SQRT( 1 - y^2)

Now, look at the Lorentz Transformation

SQRT( 1 - b^2)

where b = v/c

Which has the same form because its essentially the same thing - a
rotation, but in 4 space and the projection is into 3 space. This is
clearly shown when examining a Minkowski diagram.

But, just as Newtonian mechanics is good enough for most engineering on
Earth, conceiving of rest mass and relativistic mass as a way to
introduce the effects of relativity is perfectly acceptable. As long
as one doesn't stay there.

William

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160623634.485937.131340@m7g2000cwm.googlegroups.com...
> >
> > George Dishman wrote:
>
> <snip>
>
> >> Everything you say about the experiments is true and yes
> >> the effects are real, but in the modern approach mass is
> >> treated as invariant and the gamma function is treated as
> >> part of the relation between mass,
> >
> > REST MASS can be treated as an invariant. MASS cannot. Sorry, you
> > really don't understand the special theory of relativity if you do not
> > get this.
> >
> > http://www.physics.nyu.edu/hogg/sr/sr.pdf
>
> Excellent document. It only mentions "relativistic mass" once,
> see the first paragraph of section 6.4:
>
> "Just as in non-relativistic 3-space, where 3-momentum
> was defined as mass times 3-velocity, in spacetime
> 4-momentum ~p is mass m times 4-velocity ~u. Under this
> definition, the mass must be a scalar if the 4-momentum
> is going to be a 4-vector. If you are old enough, you may
> have heard of a quantity called "relativistic mass" which
> increases with velocity, approaching infinity as an object
> approaches the speed of light. Forget whatever you heard;
> that formulation of special relativity is archaic and ugly.
> The mass m of an object as far as we are concerned is its
> rest mass, or the mass we would measure if we were at
> rest with respect to the object."
>
> >> speed and energy. The
> >> concept of "relativistic mass" which you describe is
> >> nowadays seen as being anachronistic even if still useful
> >> in practical terms.
> >
> > Relativistic mass is important in any discussion of relativity. Sorry.
>
> "Forget whatever you heard; that formulation of special
> relativity is archaic and ugly."
>
> George

Date: 12 Oct 2006 15:46:12
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...
> George,
>
> I read the damned article before I posted it! Why the hell do you
> think I posted it? lol. I think we're arguing over nothing!

We are not arguing over physics at all. The discussion
revolves solely around nomenclature. We both known that
"rest mass" is invariant and the "relativistic mass"
varies with speed. However, the unqualified term "mass"
is slightly different but ultimately equates to "rest
mass" in the older terminology.

> To put it a little more technically, the mass 'current' in 4 space is
> the invariant because the interval along s is treated as an invariant
> in 4 space. Speed in 4 space along s (the length of the world line
> describing the position of the particle in 4 space) is an invariant.
>
> The problem with all that is that folks reading that sentence here
> won't understand a lick of it. They might start to understand it when
> they consider that a given mass sitting at rest next to them is flying
> through 4-space in the time direction at the speed of light, along with
> them! So, time is maximal and mass is minimal.
>
> When the object moves relative to them in 3 space the direction of the
> object's flux in 4 space rotates, its speed doesn't change at all along
> its path, merely the projection of its speed into 3 space changes.

Right. Now apply the same thinking to mass. What is
called "relativistic mass" is the projection of an
invariant which we call just "mass". It obviously
has the same value as the mass measured in the rest
frame of the moving body.

<snip rotation - understood >

> But, just as Newtonian mechanics is good enough for most engineering on
> Earth, conceiving of rest mass and relativistic mass as a way to
> introduce the effects of relativity is perfectly acceptable. As long
> as one doesn't stay there.

That is where time has changed. There has been a
realisation that learning something only to unlearn
it later is not a good approach even if it is valid.
Modern teaching starts with the idea of mass being
the invariant. It also avoids the usual paradoxes
such as "If a body moves fast enough, can it's mass
increase enough to become a black hole?".

George

Date: 12 Oct 2006 14:47:02
From: oriel36
Subject: Re: infinite pill-shaped universe?

Double-A

After careful consideration I have to assume that the entire community
suffers from a severe reading disability insofar as the reasons behind
'warped space' are the funniest piece of literature ever written.The
lament of light leaving stars going to waste shades into the warped
space of flatlanders -

http://bartleby.com/173/31.html

I dearly love relativity for the inventive way in dumped 'aether' on
Isaac as 'absolute space' but I say this from the dominant position of
an astronomer and do not take any of it seriously,at least technically.
With a great drumroll,relativity was introduced in 1905 as a revolution
in doing away with Newtonian aether/absolute space,it ends 100 years
later in the graffitti of a newsgroup .The reason it turns to graffitti
is that Newton explicitly rejected an aether back in 1704 but the
severe reading disability or indrination prevents people from
acknowledging that there was no aether in 1905 to reject -

"The fictitious matter which is imagined as filling the whole of space
is of no use for explaining the phenomena of Nature, since the motions
of the planets and comets are better explained without it, by means of
gravity; and it has never yet been explained how this matter accounts
for gravity. The only thing which matter of this sort could do, would
be to interfere with and slow down the motions of those large celestial
bodies, and weaken the order of Nature; and in the microscopic pores of
bodies, it would put a stop to the vibrations of their parts which
their heat and all their active force consists in. Further, since
matter of this sort is not only completely useless, but would actually
interfere with the operations of Nature, and [314] weaken them, there
is no solid reason why we should believe in any such matter at all.
Consequently, it is to be utterly rejected." Isaac 1704 .

Tommorrow you will carry on believing that Albert did something
important back in 1905 and sadly others, who know no better, will also
continue to keep the corpse dancing.What will save people will be
recognising that relativity is just a formal version of a 1898 science
fiction novel from an era when they thought they could build a machine
for anything,including 'travelling' through time.

"'Scientific people,' proceeded the Time Traveller, after the pause
required for the proper assimilation of this, 'know very well that
Time is only a kind of Space"

http://www.bartleby.com/1000/1.html

At the core of all this is the error created by Flamsteed and expanded
on by Newton,that error has the shape of a celestial sphere and it has
destroyed the better part of Western astronomy.

Double-A wrote:
> oriel36 wrote:
> > Liam wrote:
> > > Just found this CNN article where measured cosmic radioactivity seems
> > > to indicate the universe is pill-shaped:
> > > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> > >
> > > Now, I've just come to grips with the concept of the universe being
> > > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > > an infinitely thick skin of a balloon.
> > >
> > > Now this pill-shaped thing? I can't reconcile this in my mind.
> > >
> > > Could someone help me understand how both of these can be true, or
> > > whether one theory undermines the other?
> > >
> > > Thanks!
> > > Liam
> >
> > It is an incredible story how axial rotation to celestial sphere
> > geometry morphed into orbital motion to aether/absolute space and from
> > there into 'warped space' but essentially at the core of it all is this
> > -
> >
> > http://www.opencourse.info/astronomy/introduction/02.motion_stars_sun/celestial_sphere_anim.gif
> >
> > The original reason for 'bending space' is enjoyable and
> > comical,involving the lament that light leaving stars would go to waste
> > if the universe was not bent in some way,in any case you can read it
> > yourself -
> >
> > "This conception is in itself not very satisfactory. It is still less
> > satisfactory because it leads to the result that the light emitted by
> > the stars and also individual stars of the stellar system are
> > perpetually passing out into infinite space, never to return, and
> > without ever again coming into interaction with other objects of
> > nature. Such a finite material universe would be destined to become
> > gradually but systematically impoverished." Albert 1920
> >
> > Now,you can wreck you head trying to understand the latest/greatest
> > conclusion of a pill or football shaped universe or you can have an
> > enjoyable time putting these mathematicians in the position of
> > explaining the original reasoning behind warped space and the sad fate
> > of light leaving stars never to return.
> >
> > I enjoy Albert because he had a knack of latching on to the
> > obfuscations of Newton and developing novel,if not exotic,ideas from
> > them.I think people have finally outgrown the worst of the exotic
> > relativistic nonsense and I hope they can now go back and discover what
> > Isaac was really up to and the celestial sphere geometry at the core of
> > his work.
>
>
> Hi Gerald,
>
> It is interesting that the latest observaions indicate that the
> universe on the large scale is flat as far as can be seen. Countless
> numbers of galaxies are seen, and none of them seem to be repeating,
> like images in a corridor of mirrors would. The universe is huge, the
> universe is flat, no curving back on itself can be found. And this to
> my mind also calls into question the validity of the Big Bang theory.
>
> Double-A

Date: 12 Oct 2006 11:15:53
From: Double-A
Subject: Re: infinite pill-shaped universe?

oriel36 wrote:
> Liam wrote:
> > Just found this CNN article where measured cosmic radioactivity seems
> > to indicate the universe is pill-shaped:
> > http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
> >
> > Now, I've just come to grips with the concept of the universe being
> > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > an infinitely thick skin of a balloon.
> >
> > Now this pill-shaped thing? I can't reconcile this in my mind.
> >
> > Could someone help me understand how both of these can be true, or
> > whether one theory undermines the other?
> >
> > Thanks!
> > Liam
>
> It is an incredible story how axial rotation to celestial sphere
> geometry morphed into orbital motion to aether/absolute space and from
> there into 'warped space' but essentially at the core of it all is this
> -
>
> http://www.opencourse.info/astronomy/introduction/02.motion_stars_sun/celestial_sphere_anim.gif
>
> The original reason for 'bending space' is enjoyable and
> comical,involving the lament that light leaving stars would go to waste
> if the universe was not bent in some way,in any case you can read it
> yourself -
>
> "This conception is in itself not very satisfactory. It is still less
> satisfactory because it leads to the result that the light emitted by
> the stars and also individual stars of the stellar system are
> perpetually passing out into infinite space, never to return, and
> without ever again coming into interaction with other objects of
> nature. Such a finite material universe would be destined to become
> gradually but systematically impoverished." Albert 1920
>
> Now,you can wreck you head trying to understand the latest/greatest
> conclusion of a pill or football shaped universe or you can have an
> enjoyable time putting these mathematicians in the position of
> explaining the original reasoning behind warped space and the sad fate
> of light leaving stars never to return.
>
> I enjoy Albert because he had a knack of latching on to the
> obfuscations of Newton and developing novel,if not exotic,ideas from
> them.I think people have finally outgrown the worst of the exotic
> relativistic nonsense and I hope they can now go back and discover what
> Isaac was really up to and the celestial sphere geometry at the core of
> his work.

Hi Gerald,

It is interesting that the latest observaions indicate that the
universe on the large scale is flat as far as can be seen. Countless
numbers of galaxies are seen, and none of them seem to be repeating,
like images in a corridor of mirrors would. The universe is huge, the
universe is flat, no curving back on itself can be found. And this to
my mind also calls into question the validity of the Big Bang theory.

Double-A

Date: 12 Oct 2006 18:56:16
From: Mike L'Mao
Subject: Re: infinite pill-shaped universe?

Is that a caplet or a pill? If the former, the writer should think before
writing.

Date: 12 Oct 2006 10:36:43
From: oriel36
Subject: Re: infinite pill-shaped universe?

Liam wrote:
> Just found this CNN article where measured cosmic radioactivity seems
> to indicate the universe is pill-shaped:
> http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
> Now, I've just come to grips with the concept of the universe being
> infinite and expanding out of a Big...Expanding like "raisin bread" or
> an infinitely thick skin of a balloon.
>
> Now this pill-shaped thing? I can't reconcile this in my mind.
>
> Could someone help me understand how both of these can be true, or
> whether one theory undermines the other?
>
> Thanks!
> Liam

It is an incredible story how axial rotation to celestial sphere
geometry morphed into orbital motion to aether/absolute space and from
there into 'warped space' but essentially at the core of it all is this
-

http://www.opencourse.info/astronomy/introduction/02.motion_stars_sun/celestial_sphere_anim.gif

The original reason for 'bending space' is enjoyable and
comical,involving the lament that light leaving stars would go to waste
if the universe was not bent in some way,in any case you can read it
yourself -

"This conception is in itself not very satisfactory. It is still less
satisfactory because it leads to the result that the light emitted by
the stars and also individual stars of the stellar system are
perpetually passing out into infinite space, never to return, and
without ever again coming into interaction with other objects of
nature. Such a finite material universe would be destined to become
gradually but systematically impoverished." Albert 1920

Now,you can wreck you head trying to understand the latest/greatest
conclusion of a pill or football shaped universe or you can have an
enjoyable time putting these mathematicians in the position of
explaining the original reasoning behind warped space and the sad fate
of light leaving stars never to return.

I enjoy Albert because he had a knack of latching on to the
obfuscations of Newton and developing novel,if not exotic,ideas from
them.I think people have finally outgrown the worst of the exotic
relativistic nonsense and I hope they can now go back and discover what
Isaac was really up to and the celestial sphere geometry at the core of
his work.

Date: 12 Oct 2006 10:03:58
From: Double-A
Subject: Re: infinite pill-shaped universe?

William.Mook@gmail.com wrote:
> George,
>
> I read the damned article before I posted it! Why the hell do you
> think I posted it? lol. I think we're arguing over nothing!
>
> To put it a little more technically, the mass 'current' in 4 space is
> the invariant because the interval along s is treated as an invariant
> in 4 space. Speed in 4 space along s (the length of the world line
> describing the position of the particle in 4 space) is an invariant.
>
> The problem with all that is that folks reading that sentence here
> won't understand a lick of it. They might start to understand it when
> they consider that a given mass sitting at rest next to them is flying
> through 4-space in the time direction at the speed of light, along with
> them! So, time is maximal and mass is minimal.
>
> When the object moves relative to them in 3 space the direction of the
> object's flux in 4 space rotates, its speed doesn't change at all along
> its path, merely the projection of its speed into 3 space changes. The
> conception of this as a rotation is further bolstered by looking at the
> Lorentz transformation (LT) formula or 'gamma' itself! and simple
> rotational geometry
>
> Here's the formula for a circle with a radius of 1
>
> 1 = x^2 + y^2
>
> the projection of the radius on to one of the axes in terms of the
> other axis can be written as;
>
> x = SQRT( 1 - y^2)
>
> Now, look at the Lorentz Transformation
>
> SQRT( 1 - b^2)
>
> where b = v/c
>
> Which has the same form because its essentially the same thing - a
> rotation, but in 4 space and the projection is into 3 space. This is
> clearly shown when examining a Minkowski diagram.
>
> But, just as Newtonian mechanics is good enough for most engineering on
> Earth, conceiving of rest mass and relativistic mass as a way to
> introduce the effects of relativity is perfectly acceptable. As long
> as one doesn't stay there.
>
> William

I understand that the Lorentz Transformation is just a form of the
equation for a circle, but my question is, what is the rationale that
this is really the curve that nature follows?

Double-A

Date: 12 Oct 2006 13:40:03
From: Brian Tung
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
> I understand that the Lorentz Transformation is just a form of the
> equation for a circle, but my question is, what is the rationale that
> this is really the curve that nature follows?

Ultimately, it comes from the invariance of the speed of light over
coordinate transformations, which Einstein (if I recall correctly)
guessed from Maxwell's formulation of the laws of electromagnetism. If
the speed of light isn't constant, then magnetic lines don't close
properly under conditions where you would assume they would.

That alone doesn't prove that the assumption is right, but independent
observations have repeatedly vindicated Einstein's guess. (This being
science, they naturally can't ever *prove* him right.) For instance,
there is a particle called the muon, which is exactly like the electron
except that it's 207 times as massive. Otherwise, in terms of spin,
electric charge, etc., it's just like the electron.

In such situations, generally speaking, the more massive particle
tends to decay into the less massive one, and this is true in this case;
the muon decays into the electron (and a neutrino and an anti-neutrino)
with a characteristic half-life of 2.2 us (microseconds). That doesn't
mean that half of the muons decay in exactly 2.2 us--just that if you
were to measure the decay time of a bunch of muons, half of them would
have a decay time less than 2.2 us, and half would be more.

That is, however, only true for a muon at rest with respect to the
observer measuring the decay. When the muon is travelling at almost the
speed of light with respect to the observer, it turns out that the decay
time increases, exactly in accordance with the Lorentz transformations.
This and other similar observations give scientists confidence that the
special theory of relativity is correct. As I said before, you can
never *prove* it's correct, and all scientists worth their salt will
admit that, but intuitively, the chances that it's grossly in error (in
the sort of way that kooks often assert that it is) are negligible.

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Date: 13 Oct 2006 20:28:28
From: Steve Sherman
Subject: Re: infinite pill-shaped universe?

Date: 13 Oct 2006 10:08:00
From: Double-A
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> "Dana" <raff242@yahoo.com> wrote in message
> news:12iljt4nbg3cd@corp.supernews.com...
> >
> > "Double-A" <double-aa@hush.ai> wrote in message
> > news:1160432330.054745.200620@i3g2000cwc.googlegroups.com...
> >>
> >> Dana wrote:
> >> > "Double-A" <double-aa@hush.ai> wrote in message
> >> > news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
> ...
> >> > > The universe cannot have both come out of the Big Bang and be
> >> > > infinite.
> >> > > It has to be one or the other.
> >> >
> >> > Why do you say this.
> >>
> >> Was the universe infinite at one second after the Big Bang?
> >
> > OK, good point.
>
> I don't know why you say that, the equations say it
> was infinite at _all_ times if it is infinite now.
> That is, it was never anything other than infinite.
>
> "Double-A" seems to be making the common mistake of
> thinking of the initial event as an explosion in
> pre-existing space.
>
> George

No. I would never think that. But Einstein thought if you travelled
far enough in one direction, you would arrive back at your starting
point. In the early universe that trip would be relatively short. In
the older universe, that trip would be a much longer one, but never
infinite.

Double-A

Date: 14 Oct 2006 00:10:13
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"Double-A" <double-aa@hush.ai > wrote in message
news:1160759280.182929.126910@e3g2000cwe.googlegroups.com...
>
> George Dishman wrote:
>> "Dana" <raff242@yahoo.com> wrote in message
>> news:12iljt4nbg3cd@corp.supernews.com...
>> >
>> > "Double-A" <double-aa@hush.ai> wrote in message
>> > news:1160432330.054745.200620@i3g2000cwc.googlegroups.com...
>> >>
>> >> Dana wrote:
>> >> > "Double-A" <double-aa@hush.ai> wrote in message
>> >> > news:1160425623.105160.196070@m7g2000cwm.googlegroups.com...
>> ...
>> >> > > The universe cannot have both come out of the Big Bang and be
>> >> > > infinite.
>> >> > > It has to be one or the other.
>> >> >
>> >> > Why do you say this.
>> >>
>> >> Was the universe infinite at one second after the Big Bang?
>> >
>> > OK, good point.
>>
>> I don't know why you say that, the equations say it
>> was infinite at _all_ times if it is infinite now.
>> That is, it was never anything other than infinite.
>>
>> "Double-A" seems to be making the common mistake of
>> thinking of the initial event as an explosion in
>> pre-existing space.
>
> No. I would never think that.

OK. I apologise for misinterpreting your comments. I was
reading between the lines and got it wrong.

> But Einstein thought if you travelled
> far enough in one direction, you would arrive back at your starting
> point. In the early universe that trip would be relatively short. In
> the older universe, that trip would be a much longer one, but never
> infinite.

That would be true for a closed universe in which
the density exceeded the critical value. He would
also have been aware that a density equal to or
lower than the critical value would produce an
infinite universe. Recent measurements suggest it
is less likely that it is closed. The main point
is that the spatially infinite universe has always
been a valid solution to the equations of GR which
describe the 'big bang' universe.

George

Date: 14 Oct 2006 21:02:13
From:
Subject: Re: infinite pill-shaped universe?

dlzc wrote:
> Dear William Mook:
>
> Since this is "tempest in a teapot"...
>
> William.Mook@gmail.com wrote:
> > N:dlzc D:aol T:com (dlzc) wrote:
> > > Dear William.Mook:
> > >
> > > <William.Mook@gmail.com> wrote in message
> ...
> > > Baez says mass is rest mass:
> > > http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
> >
> > Hold on now skippy, Baez says this at the outset;
> >
> > "There is sometimes confusion surrounding the subject of mass in
> > relativity. This is because there are two separate uses of the term.
> > Sometimes people say "mass" when they mean "relativistic mass",
> > mr but at other times they say "mass" when they mean
> > "invariant mass","
> >
> > Which pretty much is what I'm saying. So, what's your point?
>
> You have been circumspect in your writings, up until this thread, when
> you claim that "mass" is always "relativistic mass":

Jesus man, what's your beef? lol. Never said mass is always
relativisitc mass sorry. I am using terminology that seem natural to
me. Obviously you are the sort of person who likes to browbeat your
students into accepting things contrary to their natural understanding
of things. This creates an easily managed uniform sort of student
body, but the resulting understanding is fragile at best, temporary and
meaningless at worst.

Difficult questions arising from fundamental life experience is what
folks who teach get trained to beat through day in and day out.
Defining away things as if definitions were handed down from God is a
low way to knowledge. What is handed down from God is the wiring in
each of our brains. And making peace with that is not achieved by
arbitrary definitons absent any further work.

Its hard work being a good student.

Its hard work being an good instructor

Arbitrary definitions that don't do honor to a student's deep seated
prejudice and life experience aren't worth the paper they're printed
on.

> http://groups.google.com/group/sci.astro.amateur/msg/5ab9a4a05fdf1593
> http://groups.google.com/group/sci.astro.amateur/msg/8fff4b22e91d0786
>
> > > Hillman says mass is rest mass:
> > > http://groups.google.com/group/sci.physics/msg/6f1f1b991a0e6c26
> >
> >
> > Hillman quotes Taylor and Wheeler, but not before saying this;
> >
> > expunge everything you've ever read about "relativistic mass" from your
> > memory; think rather in terms of "relativistic kinetic energy" and your
> > life in physics will be much easier
> >
> > Which again pretty much supports what I've said.
>
> Up until you claim that "mass" is "relativistic mass", you have not
> said anything wrong.

Dude, I said invariant mass is rest mass, mass of a moving object
varies.

> Even that is not wrong, but it is an archaic use.

The archaic use as you call it derives from the field of experience we
come to school with. As far as the hard wiring in our brains is
concerned we live an a 3-dimensional space and move through time. This
archaic 3+1 notion of spacetime is the native or natural condition
everyone finds themselves in. Defining away this prejudice just to
make your job easier in training half-witted dolts who don't connect
their training to their experience is worse than useless. It detracts
from the ability of the students to really and deeply understand what
they are being asked to learn - all to ease the burden on the educator
- so called!

> > > Taylor and Wheeler say mass is rest mass:
> > > "Spacetime Physics"
> >
> > ??? Wheeler had an argument with the publisher over putting
> > his name on this elementary text BECAUSE of its use of
> > relativistic mass!!! It was only when he was allowed to say
> > derogatory things about the use of the term that he put his
> > name on it!
> >
> > Explaining that there is a difference between rest mass which
> > is an invariant and relativistic mass to a popular audience
> > interested in relativity is pretty much what all these authors have
> > done - in much the same way I have done it.
>
> "Pretty much" is not "the same".

Pretty much is pretty much the same. You are not clearly stating your
point here. What is your point exactly?

>
> > > Gary Oas says mass is rest mass:
> > > http://adsabs.harvard.edu/abs/2005physics...4110O
> > >
> > > ... and here
> > > http://arxiv.org/abs/physics/0504110
> >
> > But the Harvard physicist DEFINES mass as rest mass
> > eschewing all other discussions of mass as being
> > nonsensical only AFTER saying that relativistic mass is,
> > "a heuristic device a preliminary study of first time learners"
> > in both papers.
> >
> > Which pretty much supports what I was saying to the
> > usenet group here.
>
> Not at all.

Yes. I said that rest mass was an invariant. The mass of a moving
body is not and is described by the Loretnz transformation for
relativistic mass. Which is true.

> You claim that mass = relativistic mass,

No, I said that the rest mass was an invariant and that the mass of a
moving body varies according to the Lorentz transformation for
relativistic mass. Which is correct.
.

> regardless of
> context or intent. At least in *this* thread.

I said that the rest mass was an invariant and that the mass of a
moving body varies according to the Loretnz transformation for
relativisitc mass. Which is accurate.

> > > ... a mixed bag on this site...
> > > http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html#mas
> > > ... with lots of disclaimers.
> > >
> > > Your usage is non standard, you will get in trouble if you try
> > > and use formulae based on mass = rest mass.
> >
> > Never did that. I did say invariant mass IS rest mass! lol.
> > Which is PRECISELY what YOU are spouting here.
> >
> > Perhaps you should include on your reading list,
> >
> > "In defense of relativistic mass," by T. R. Sandin, Am. J. Phys. 59,
> > 1032 (1991)
>
> Why does your electron stream not accelerate transverse to its path
> (via a magnetic field) based on its relativistic mass? How is it that
> mass, a scalar, has vector behavior? Momentum has the expectation of
> carrying vector information... why not leave it there?

I won't argue with you at this level when you have misquoted and
misconstrued a rather simple statement in such a way as to make it seem
I'm saying something I'm not. And you're rather rude anyway, so I'll
not answer your stupid question.

> > > And exclamations of
> > > "bullshit" are unconvincing.
> >
> > I didn't use the term sir, but be warned, if you spout bullshit,
> > it will be called such! lol.
>
> http://groups.google.com/group/sci.astro.amateur/msg/f236715765b3ffe2
> ... perhaps someone spoofed your header here?

No. You are quoting out of context. I did say bullshit in reply to
THAT comment because that comment was bullshit. I did not say bullshit
in reply to THIS comment, which was pretty much a series of rational
questions demanding a rational response, which I provided. Now your
response here in THIS commentary, IS UNADULTERATED BULLSHIT! Using
words and stuff quoted out of context to obsfuscate as if that ever won
an argument honestly! sheez.
.
>
> > > And hints that everyone else
> > > doesn't understand special relativity should give you a clue.
> >
> > Never said that either, that's all in YOUR head! and I'm not
> > responsible for it! lol..
>
> http://groups.google.com/group/sci.astro.amateur/msg/8fff4b22e91d0786
> <QUOTE>
> Sorry, you really don't understand the special theory of relativity if
> you do not
> get this.
> <END QUOTE>

Let's see, you quote me out of context, yet even in the quote you have
me saying

"if you don't get X you don't understand the theory of relativity"

and you CLAIM that this is the same as me "hints that everyone doesn'
understand special relativity"

Please defend this equation and show that it does not exist in your
head.

Or more clearly, explain why someone saying

"If you don't get X then Y"

is the same in your head as

"No one gets Y"

YOU ARE MAKING THIS CONNECTION! So, I don't really have to answer it.
I said if someone doesn't know how relativisitc mass works, then they
don't understand special realtivity, not in a fundamental way. When
pressed on the matter, I explain and defend my position.

Now, because I transgressed some religious definitions you want to
impress on your besotted students, you are claiming that I am hinting
that everyone doesn't understand special relativity.

Well, if they haven't given any thought to relativisitic mass and how
it is explained as a projection of a 4-vector into 3-space then I would
say they DON'T! lol. Which just repeats what you quoted - BUT DOESN'T
SUPPORT IN THE LEAST YOUR ERRONEOUS ASSUMPTION THAT I'M HINTING NO ONE
GETS RELATIVITY!

So, I don't have to answer your damned stupid question arising as it
does in your head, not my action.

> "This" being "mass is relativistic mass".
>
> That isn't the only example. It isn't in my head, but in your words.

You concluding that I'm hinting no one gets relativity because I say
that if you don't understand relativistic mass you don't get relativity
is a conclusion that occurs in YOUR head, not in my words. Live with
it.

> > > Believe what you will. I just wish you didn't spread
> > > antiquated usage around like it was gospel.
> >
> > You're the one who's offended by my total lack of respect for
> > Wheeler's gospel mass IS rest mass! lol.
>
> My offense isn't at most of what you say, William. I did provide a
> reference to your very words, remember?

Taken out of context. I mean, look at the bullshit you're trotting
out. I say I didn't call your response bullshit but responded to it
rationally, and then you pull up other responses to other discussions
where I did say bullshit and then call me a liar. What kind of
bullshit is that? lol. I DID NOT say I NEVER said bullshit EVER. I
said in response to your accusation that I was responding rationally to
your rational points. IN RESPONSE TO MY RATIONAL RESPONSE YOU LAY ON
THE BULLSHIT! hahahahaha..

God only knows what you'll say now! One thing's for certain. It won't
be rational.

> As to offense, why is it that
> "path-transverse mass" isn't the same as "path-parallel mass" when
> using "relativistic mass"? If your concern is not to confuse "the
> masses", how can you support such a double standard?

I have fully explained myself throughout this response. Students come
to class hard-wired with a certain understanding of the world, as did
Einstein himself. And just as Einstein did, those to created this
theory found the idea of relativisitic mass useful in connecting that
natural hard-wired experience to a deep understanding of what was going
on. So, I am of the opinion that honoring this deep seated
misconception is an important step to true learning. And I am also of
the opinion that ignoring this natural conception of reality through
bullshit definitions does a huge diservice to students. They emerge
from such an experience thinking about the real world and the
relativistic world. The world they talk about and the world they do
their relativisitic physics in. The world where natural definitions
apply and the world where artificially constructed definitions apply.
It avoids them making a fundamental and emotional connection to this
knowledge base that is important for any significant work to be done
with it.

> > David, this whole discussion makes it seem that mass is
> > such an important quantity. Actually what we should be
> > talking about is momentum current along the world line in
> > 4 space of an object. But that's so far removed from what
> > the original point of discussion was introducing it then
> > would just be lording one's knowledge over others for no real
> > purpose.
>
> You are "lording over" your particular choice of definition of terms,

Bullshit. I am using terms that occur naturally to me and everyone
else. You are the one demanding I use definitions according to what
the specialists say should be used to ease understanding of the subject
by sweeping certain common misconceptions under the rug.

At one point you say there are common misconceptions that are avoided
by proper definitions of terms at the outset. Then you object that my
usage reinforces those misconceptions. Now you are claiming I'm
lording over my particular choice of terms. All the while ignoring why
the hell everyone (otherwise it wouldn't be common) has all these same
misconceptions to start out with.

So, lets get down to reality. Our minds and perception of reality is
molded through evolution to understand the world in newtonian terms.
That's why the 'archaic' usages arose in the first place. Relativistic
mass was a stepping stone to understanding what was going on in
4-space. It allows deep connections to be made.

Defining things at the outset to minimize this 'confusion' as you call
it, may minimize difficult and oft repeated questions from students.
But I get the sense you and others use it to brow beat students into
submission and make the understanding your impart to them narrow and
meaningless rather than deep and meaningful.

In short, your definition is no more than a labor saving device and
those paying for the savings are the students you inflict with your
inane definitions - no matter how well defended or reasoned.

> and "denigrating" anyone that doesn't use it. Your hands appear soiled
> too.

You can do whatever you like. But the bottom line is the student
satisfied with his level of knowledge, or is he/she left with a nagging
suspicion that they've been sold a bill of goods. To the extent
students take their studies seriously and wish to connect with their
studies in a deep way, they will uniformly have trouble with made up
bullshit like this.

> Do we speak the same words with different meanings

hahaha... you get upset that I used the word 'mass' in a non-standard
archaic way, you pull up bullshit from other discussions and quote me
out of context, and now you accuse me of speaking the same words with
different meanings! lol. What a joke!

> (pure chaos, where
> "the masses" live),

Dude, I said rest mass is an invariant and that the mass of a moving
object varies according to the Lorentz transformation. This is
accurate. You have not explained the trouble you have with the
statement other than to say that modern usage defines mass to mean rest
mass and doesn't use the term relativistic mass at all since its
archaic and old fashioned.

I think that may fly with a bunch of 18 year olds who just want to get
through a course in physics, but it doesn't fly with me FOR THE REASONS
I'VE AMPLY STATED!

Rather than address my concerns as I have stated them, you have
attempted to misquote me and accuse me of all sorts of things I didn't
do. THIS IS BULLSHIT! And I don't need to answer it. I will however
answer any reasonable observation of what I really did say! lol.

> do we qualify everything we say (safest), or do we
> codify the English language (pushing all creativity out of it).

The English language or any other natural language, does not exist in
isolation as some mental construct. A language makes deep connections
to what's inside each of us. Great poetry from the 13th century
romantics have a capacity to touch us today because such connections
exist. No work of literature would be worth much without these
connections to human experience.

English language as it is used to describe our physical world should
also make such connections deeply into the human experience if we are
to have a physics that means anything to anyone. No workof science is
worth much without these connections to human experience.

Our ability to create things of value stems from exercising the results
of these connections. Defining things to AVOID such connections
because it makes teaching a particular subject easier is a measure of
our decline as a culture. Its like removing a tasty ingredient from a
recipe because it makes the preparation easier and then ridiculing
someone when they say its tasteless pap! lol.

> My agenda is to inform where the physics community is going.

I don't know that I have an agenda per se. I do think its important to
honor the misperceptions of students and to do the hard work of helping
them forge those connections that are so critical for a deep and rich
understanding of a subject. Defining things out of existence seems to
me to be an absive sort of tactic that brow beats the students and
shames them into acceptance while isolating them from a deep and rich
understanding of a subject.

> I
> understand that you know the history, and don't seem to care where it
> is going. So what is your agenda?

As I said, I don't have an agenda per se. Of course if in the context
of replying to your point I did say I had an agenda I'm sure you would
use such a statement out of context to create the impression I was
being unreasonable! lol. That's what I think YOUR agenda is. But as
I've said, I don't have an agenda. I merely said something about
relativity in response to some damn fool thing someone said, and I find
I'm the object of your misanthropic attention! lol. Now you're
demanding to know my agenda. Well, I don't have one. I do think
though it unfortunate that folks who should be honoring the
misconceptions of students in order to take them carefully thorugh to
deep and rich understanding, are doing nothing of the kind in this
important subject. And that's just too damn bad.

> When will you (next) write a
> physics text?

When I do write a physics text I will honor the connections that exist
naturally in the human psyche to the natural world, and in so honoring
those connections I will impart a rich and deep appreciation that your
bogus definition that ignores relativistic mass in any discussion of
special relativity fails to impart.

> Your words can be the last.

goody - we'll see if that's so! lol.

Date: 14 Oct 2006 20:34:31
From: Double-A
Subject: Re: infinite pill-shaped universe?

William.Mook@gmail.com wrote:
> Double-A wrote:
> >
> >
> > I understand that the Lorentz Transformation is just a form of the
> > equation for a circle, but my question is, what is the rationale that
> > this is really the curve that nature follows?
> >
> > Double-A
>
> The same rationale anything is accepted as scientific fact.
> Experimental results that backit up.
>
> Let's look at the history and things will be clear.
>
> The whole thing started when two Ohio physicists, Michelson and Moreley
> did an experiment at the end of the 19th century with an interferometer
> to figure things out about light.
>
> They wanted to detect the effect of Earth's motion on the ether.
>
> See, a guy named Maxwell had developed a set of differential equations
> that described light as a multi-dimensional wave, and there were a few
> things the equations predicted about the medium of wave transmission
> that folks wanted to figure out.
>
> Folks thought about light in that day and time the way they thought
> about sound. Sound waves are variation in air pressure that move at
> the speed of sound through the air. Light waves as Maxwell described
> them were variations in electromagnetic potential in an electromagnetic
> medium people called ether or aether. Disturbances in the aether they
> thought would radiate from the point of disturbance at the speed of
> light.
>
> So, Michelson and Morely set up this experiment to detect the effects
> of the Earth's motion through space which is a large enough fraction of
> light speed to detect, in order to figure out stuff about the ether and
> what was up with that. They wanted to characterise ether by measuring
> light the same way someone might characterise air by measuring the
> speed of sound..
>
> Michelson Morely got a null result. There didn't appear to be any
> ether!
>
> Lorentz reading the Michelson Moreley paper attempted to explain this
> result as the ether pushing against matter squeezing it in the
> direction of motion. This would nullify optical experiment Michelson
> Morely were doing with their interferometer since the experiment
> assumed the interferometer didn't change length as it changed
> direction.
>
> Einstein looking at Lorentz's paper when it was published had a aha
> moment when he realized we were dealing with the rotation of an
> invariant 4-momentum that was moving at the speed of light through 4
> dimensions, and that there was no ether required to explain anything.
>
> Einstein went on and dashed off his special theory of relativity where
> he showed among other things that rest mass is the same as energy
> (which neatly explained Madame Curies curious results with Radium,where
> did all that energy come from? - the decay of matter according to
> Einstein!)
>
> The mathematician Minkowski was enamoured of this paper of Einstein's
> as we everyone generally, and he helped Einstein with higher
> dimensional math. He came up with Minkowski spacetime, and Einstein
> produced the General theory of relativity shortly thereafter after
> being instructed by Minkowski. (Einstein didn't really have a degree,
> he was a patent clerk at the Swiss patent office in Bern Switzerland,
> to escape the draft in Germany which was instituted at that time! He
> also wanted to separate from a woman he impregnated in Italy the
> previous summer - this vacation was when he famously wondered what it
> would be like riding a bicycle at the speed of light? Would someone
> become like a vampire and not be able to see their reflection?)
>
> One of the things Einstien predicted, other than the null result of
> Michelson Morely, was that Mercury's orbit would be non-Newtonian (it
> is, advancing in its orbit exactly in the amount Einstein predicted)
> and that star positions when viewed near the solar surface would be
> slightly distorted due to gravity (it is, exactly in the amount
> Einstien predicted during the very next total eclipse) and that the
> Sun's gravity would cause light originating on its surface to redden as
> it rose radially from the center (it does, spectra of elements in the
> sun are shifted just as Einstien predicted)
>
> This is a lot of stuff for one simple observation and a few
> calculations to predict! And it earned Einstein a place in the history
> of physics equal to that of Newton! A lot of noteriety! And a lot of
> honorary degrees and ultimately a position at Princeton's Institute of
> Advanced Studies. All of which was well deserved.

Thanks for the overview.

Double-A

Date: 14 Oct 2006 20:05:38
From:
Subject: Re: infinite pill-shaped universe?

Double-A wrote:
>
>
> I understand that the Lorentz Transformation is just a form of the
> equation for a circle, but my question is, what is the rationale that
> this is really the curve that nature follows?
>
> Double-A

The same rationale anything is accepted as scientific fact.
Experimental results that backit up.

Let's look at the history and things will be clear.

The whole thing started when two Ohio physicists, Michelson and Moreley
did an experiment at the end of the 19th century with an interferometer
to figure things out about light.

They wanted to detect the effect of Earth's motion on the ether.

See, a guy named Maxwell had developed a set of differential equations
that described light as a multi-dimensional wave, and there were a few
things the equations predicted about the medium of wave transmission
that folks wanted to figure out.

Folks thought about light in that day and time the way they thought
about sound. Sound waves are variation in air pressure that move at
the speed of sound through the air. Light waves as Maxwell described
them were variations in electromagnetic potential in an electromagnetic
medium people called ether or aether. Disturbances in the aether they
thought would radiate from the point of disturbance at the speed of
light.

So, Michelson and Morely set up this experiment to detect the effects
of the Earth's motion through space which is a large enough fraction of
light speed to detect, in order to figure out stuff about the ether and
what was up with that. They wanted to characterise ether by measuring
light the same way someone might characterise air by measuring the
speed of sound..

Michelson Morely got a null result. There didn't appear to be any
ether!

Lorentz reading the Michelson Moreley paper attempted to explain this
result as the ether pushing against matter squeezing it in the
direction of motion. This would nullify optical experiment Michelson
Morely were doing with their interferometer since the experiment
assumed the interferometer didn't change length as it changed
direction.

Einstein looking at Lorentz's paper when it was published had a aha
moment when he realized we were dealing with the rotation of an
invariant 4-momentum that was moving at the speed of light through 4
dimensions, and that there was no ether required to explain anything.

Einstein went on and dashed off his special theory of relativity where
he showed among other things that rest mass is the same as energy
(which neatly explained Madame Curies curious results with Radium,where
did all that energy come from? - the decay of matter according to
Einstein!)

The mathematician Minkowski was enamoured of this paper of Einstein's
as we everyone generally, and he helped Einstein with higher
dimensional math. He came up with Minkowski spacetime, and Einstein
produced the General theory of relativity shortly thereafter after
being instructed by Minkowski. (Einstein didn't really have a degree,
he was a patent clerk at the Swiss patent office in Bern Switzerland,
to escape the draft in Germany which was instituted at that time! He
also wanted to separate from a woman he impregnated in Italy the
previous summer - this vacation was when he famously wondered what it
would be like riding a bicycle at the speed of light? Would someone
become like a vampire and not be able to see their reflection?)

One of the things Einstien predicted, other than the null result of
Michelson Morely, was that Mercury's orbit would be non-Newtonian (it
is, advancing in its orbit exactly in the amount Einstein predicted)
and that star positions when viewed near the solar surface would be
slightly distorted due to gravity (it is, exactly in the amount
Einstien predicted during the very next total eclipse) and that the
Sun's gravity would cause light originating on its surface to redden as
it rose radially from the center (it does, spectra of elements in the
sun are shifted just as Einstien predicted)

This is a lot of stuff for one simple observation and a few
calculations to predict! And it earned Einstein a place in the history
of physics equal to that of Newton! A lot of noteriety! And a lot of
honorary degrees and ultimately a position at Princeton's Institute of
Advanced Studies. All of which was well deserved.

Date: 14 Oct 2006 19:36:27
From:
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...
> > George,
> >
> > I read the damned article before I posted it! Why the hell do you
> > think I posted it? lol. I think we're arguing over nothing!
>
> We are not arguing over physics at all. The discussion
> revolves solely around nomenclature.

Alright.

> We both known that
> "rest mass" is invariant

Yes.

> and the "relativistic mass"
> varies with speed.

Yes because the projection of the 4-space mass flux into 3-space
changes with speed in 3-space.

> However, the unqualified term "mass"
> is slightly different but ultimately equates to "rest
> mass" in the older terminology.

Alright.

> > To put it a little more technically, the mass 'current' in 4 space is
> > the invariant because the interval along s is treated as an invariant
> > in 4 space. Speed in 4 space along s (the length of the world line
> > describing the position of the particle in 4 space) is an invariant.
> >
> > The problem with all that is that folks reading that sentence here
> > won't understand a lick of it. They might start to understand it when
> > they consider that a given mass sitting at rest next to them is flying
> > through 4-space in the time direction at the speed of light, along with
> > them! So, time is maximal and mass is minimal.
> >
> > When the object moves relative to them in 3 space the direction of the
> > object's flux in 4 space rotates, its speed doesn't change at all along
> > its path, merely the projection of its speed into 3 space changes.
>
> Right. Now apply the same thinking to mass.

What we call rest mass is merely the projection of the mass-flux, or
momentum into 3-space when the mass is not moving relative to the
observer.

> What is
> called "relativistic mass" is the projection of an
> invariant which we call just "mass". It obviously
> has the same value as the mass measured in the rest
> frame of the moving body.

4-space is a mental construct, a damned useful mental construct, but a
mental construct nevertheless. The only thing we have access to is
what we see in 3-space. And what we see in 3-space is rest mass and
the mass of a moving object. So called relativistic mass.

Similarly with decay times of particles moving slowly and
relativisitically distorted decay times of the same particle types
moving rapidly.

These can all be thought of as invariant masses and invariant intervals
rotating in 4-space and us observing the projection in 3-space as their
relative velocity changes. However, we as inhabitants of 3-dimensions
experiencing the 4th dimension as a constant flux we call 'time' - the
older still antiquated notion of 3+1 spacetime - is what we're stuck
with experientially, and connecting to our fundamental experience of
reality pays dividends in understanding, despite the wrinkles is
produces to a clear understanding of what's going on in 4-space.

>
> <snip rotation - understood>
>
> > But, just as Newtonian mechanics is good enough for most engineering on
> > Earth, conceiving of rest mass and relativistic mass as a way to
> > introduce the effects of relativity is perfectly acceptable. As long
> > as one doesn't stay there.
>
> That is where time has changed.

Our fundamental human experience of spacetime reality has not changed.
That's the point.

> There has been a
> realisation that learning something only to unlearn
> it later is not a good approach even if it is valid.

This is where we disagree. We are not learning something to unlearn
it. We are referencing something fundamental and innate in the way
humans experience spacetime reality without being taught. We must deal
with innate Newtonian wiring of human conciousness and use it to
illuminate what is going on with 4-dimensional rotations.

> Modern teaching starts with the idea of mass being
> the invariant.

As a concept that's fine. It does nothing to address what we see when
we peer across space and time and observe moving masses.

> It also avoids the usual paradoxes
> such as "If a body moves fast enough, can it's mass
> increase enough to become a black hole?".

As you ride along in an accelerating spacecraft you will observe the
sky foreshortening in front of the spacecraft, blue shifted, and
foreshortening in the rear of the spacecraft red shifted, the space
around the disk normal to motion is empty. Why? Because in part the
vehicle cannot travel in those direction at the speed it is travelling.
Those directions don't exist. This is very similar to the Killing
vectors and rotation of the light cone as one approaches the horizon of
a black hole. Up no longer exists below the event horizon, just like
sideways no longer exists in a speeding spacecraft.

Similarly, an accelerating spacecraft will emit Unruh radiation,
analysis of this is effect is what led Hawking to postulate that black
holes were not black.

So, such 'stupid' questions are really rather enlightening if
approached with care and respect they deserve.

I think defining questions out of existence to make things easier for
instructors is the mark of a lazy society, one in deep decline. And I
resist such notions.

William

Date: 15 Oct 2006 12:47:13
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1160879786.993712.95180@k70g2000cwa.googlegroups.com...
>
> George Dishman wrote:
>> <William.Mook@gmail.com> wrote in message
>> news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...
>> > George,
>> >
>> > I read the damned article before I posted it! Why the hell do you
>> > think I posted it? lol. I think we're arguing over nothing!
>>
>> We are not arguing over physics at all. The discussion
>> revolves solely around nomenclature.
>
> Alright.
>
>> We both known that
>> "rest mass" is invariant
>
> Yes.
>
>> and the "relativistic mass"
>> varies with speed.
>
> Yes because the projection of the 4-space mass flux into 3-space
> changes with speed in 3-space.
>
>> However, the unqualified term "mass"
>> is slightly different but ultimately equates to "rest
>> mass" in the older terminology.
>
> Alright.
>
>> > To put it a little more technically, the mass 'current' in 4 space is
>> > the invariant because the interval along s is treated as an invariant
>> > in 4 space. Speed in 4 space along s (the length of the world line
>> > describing the position of the particle in 4 space) is an invariant.
>> >
>> > The problem with all that is that folks reading that sentence here
>> > won't understand a lick of it. They might start to understand it when
>> > they consider that a given mass sitting at rest next to them is flying
>> > through 4-space in the time direction at the speed of light, along with
>> > them! So, time is maximal and mass is minimal.
>> >
>> > When the object moves relative to them in 3 space the direction of the
>> > object's flux in 4 space rotates, its speed doesn't change at all along
>> > its path, merely the projection of its speed into 3 space changes.
>>
>> Right. Now apply the same thinking to mass.
>
> What we call rest mass is merely the projection of the mass-flux, or
> momentum into 3-space when the mass is not moving relative to the
> observer.

Not quite, as I'm sure you know. AIUI, "momenergy"
(horrible word) is a 4-vector and when you project
that onto the 3 spatial axes you get the momentum.
Projecting it onto the time axis gives you the total
energy. Mass (*c^2) is the magnitude of the momenergy
so "rest mass" is the projection of momenergy onto
the worldline of the particle and kinetic energy is
the difference between that the total energy.

>> What is
>> called "relativistic mass" is the projection of an
>> invariant which we call just "mass". It obviously
>> has the same value as the mass measured in the rest
>> frame of the moving body.
>
> 4-space is a mental construct, a damned useful mental construct, but a
> mental construct nevertheless.

No, 4D spacetime is what we actually live in and the
3D world with Newton's 'absolute time' that we see is
a subset produced by our limited experience of motion
at relativistic speeds.

> The only thing we have access to is
> what we see in 3-space. And what we see in 3-space is rest mass and
> the mass of a moving object. So called relativistic mass.
>
> Similarly with decay times of particles moving slowly and
> relativisitically distorted decay times of the same particle types
> moving rapidly.
>
> These can all be thought of as invariant masses and invariant intervals
> rotating in 4-space and us observing the projection in 3-space as their
> relative velocity changes.

Exactly, that is how SR is taught these days. The
high energy guys tend to take of the "mass shell".

> However, we as inhabitants of 3-dimensions
> experiencing the 4th dimension as a constant flux we call 'time' - the
> older still antiquated notion of 3+1 spacetime - is what we're stuck
> with experientially, and connecting to our fundamental experience of
> reality pays dividends in understanding, despite the wrinkles is
> produces to a clear understanding of what's going on in 4-space.

Well that is not the view of academia or physicists
today. Most modern teaching AFAIK starts with the
4D view and for GR there is a trend toward coordinate-
free differntial geometry.

>> <snip rotation - understood>
>>
>> > But, just as Newtonian mechanics is good enough for most engineering on
>> > Earth, conceiving of rest mass and relativistic mass as a way to
>> > introduce the effects of relativity is perfectly acceptable. As long
>> > as one doesn't stay there.
>>
>> That is where time has changed.
>
> Our fundamental human experience of spacetime reality has not changed.
> That's the point.

No, my point is that scientific teaching has departed
from the old approach of starting with human experience.

>> There has been a
>> realisation that learning something only to unlearn
>> it later is not a good approach even if it is valid.
>
> This is where we disagree. We are not learning something to unlearn
> it. We are referencing something fundamental and innate in the way
> humans experience spacetime reality without being taught. We must deal
> with innate Newtonian wiring of human conciousness and use it to
> illuminate what is going on with 4-dimensional rotations.

You are not disagreeing with me, you are disagreeing
with current practice. I am merely bringing that to
your attention.

>> Modern teaching starts with the idea of mass being
>> the invariant.
>
> As a concept that's fine. It does nothing to address what we see when
> we peer across space and time and observe moving masses.

Not at all, obviously the concept includes that of
projecting the invariant onto coordinates to get the
measurable but that makes it clear that "relativistic
mass" is just a name for a partial term in the fomula
for total energy.

>> It also avoids the usual paradoxes
>> such as "If a body moves fast enough, can it's mass
>> increase enough to become a black hole?".
>
> As you ride along in an accelerating spacecraft you will observe the
> sky foreshortening in front of the spacecraft, blue shifted, and
> foreshortening in the rear of the spacecraft red shifted, the space
> around the disk normal to motion is empty. Why? Because in part the
> vehicle cannot travel in those direction at the speed it is travelling.
> Those directions don't exist. This is very similar to the Killing
> vectors and rotation of the light cone as one approaches the horizon of
> a black hole. Up no longer exists below the event horizon, just like
> sideways no longer exists in a speeding spacecraft.
>
> Similarly, an accelerating spacecraft will emit Unruh radiation,
> analysis of this is effect is what led Hawking to postulate that black
> holes were not black.
>
> So, such 'stupid' questions are really rather enlightening if
> approached with care and respect they deserve.

I entirely agree, I didn't say they were 'stupid'. In
fact that particular paradox is quite useful in showing
how "relativistic mass" can be a misleading concept.

> I think defining questions out of existence to make things easier for
> instructors is the mark of a lazy society, one in deep decline. And I
> resist such notions.

On the other hand, teaching in such a way that such
questions, which are indicative of a poor understanding
of the subject, don't arise in the first place shows an
improvement in the method. The paradoxes are still
covered but resolving them becomes trivial.

George

Date: 15 Oct 2006 07:30:58
From:
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160879786.993712.95180@k70g2000cwa.googlegroups.com...
> >
> > George Dishman wrote:
> >> <William.Mook@gmail.com> wrote in message
> >> news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...
> >> > George,
> >> >
> >> > I read the damned article before I posted it! Why the hell do you
> >> > think I posted it? lol. I think we're arguing over nothing!
> >>
> >> We are not arguing over physics at all. The discussion
> >> revolves solely around nomenclature.
> >
> > Alright.
> >
> >> We both known that
> >> "rest mass" is invariant
> >
> > Yes.
> >
> >> and the "relativistic mass"
> >> varies with speed.
> >
> > Yes because the projection of the 4-space mass flux into 3-space
> > changes with speed in 3-space.
> >
> >> However, the unqualified term "mass"
> >> is slightly different but ultimately equates to "rest
> >> mass" in the older terminology.
> >
> > Alright.
> >
> >> > To put it a little more technically, the mass 'current' in 4 space is
> >> > the invariant because the interval along s is treated as an invariant
> >> > in 4 space. Speed in 4 space along s (the length of the world line
> >> > describing the position of the particle in 4 space) is an invariant.
> >> >
> >> > The problem with all that is that folks reading that sentence here
> >> > won't understand a lick of it. They might start to understand it when
> >> > they consider that a given mass sitting at rest next to them is flying
> >> > through 4-space in the time direction at the speed of light, along with
> >> > them! So, time is maximal and mass is minimal.
> >> >
> >> > When the object moves relative to them in 3 space the direction of the
> >> > object's flux in 4 space rotates, its speed doesn't change at all along
> >> > its path, merely the projection of its speed into 3 space changes.
> >>
> >> Right. Now apply the same thinking to mass.
> >
> > What we call rest mass is merely the projection of the mass-flux, or
> > momentum into 3-space when the mass is not moving relative to the
> > observer.
>
> Not quite, as I'm sure you know. AIUI, "momenergy"
> (horrible word) is a 4-vector and when you project
> that onto the 3 spatial axes you get the momentum.
> Projecting it onto the time axis gives you the total
> energy. Mass (*c^2) is the magnitude of the momenergy
> so "rest mass" is the projection of momenergy onto
> the worldline of the particle and kinetic energy is
> the difference between that the total energy.

Well, lets define terms a little - since that got us into trouble last
time! haha... This is utterly called for when you use a technical
term like 'momenergy' which neatly summarizes a few ideas folks have
about spacetime! lol.

momenergy doesn't have an archaic usage since it was made up in the
last 50 years, and avoids the use of archaic terms like 'mass' which
have deep connections with our life experience going back to the
beginning of humanity.

So, using definitions like this is appropriate in my view since its
brand-new and useful! lol.

Alright,what the hell is momenergy in 4-dimensiona spacetime? haha

That's what I can see someone thinking who reads this.

Well momentum is mass times velocity, and velocity is the differential
of position with respect to time. Now, in 3D space time is a scalar.
In 4D spacetime it is a vector. The problem is to create a sort of
physics we are familiar with in 3D using our new 4D spacetime
understanding of things. That means the results have to transform
properly under Lorentzian transformations. How to do this?

Time is a scalar in 3D space and can be easily transformed but time a
vector in 4D spacetime and doesn't transform. So, we've got to figure
out a scalar equivalent for time when physics is expressed in terms of
a 4D vector. See?

So, one way to do it is consider the length along the spacetime vector
as an invariant.

Well, recall that between any two events in space time there is a time
interval (delta t) and three coordinate differences (space intervals)
(delta x, delta y, delta z (assuming cartesian coordinates))

So a four-vector a lot like a three-vector is built.

f_ = (delta t, delta x, delta y, delta z)

There is an invariant scalar (tau) associated with each four-vector
defined as;

f_ dot f_ = (delta t)^2 - (delta x)^2 - (delta y)^2 - delta z)^2 =
tau ^2

The nature of this dot products defines the nature of Lorentzian
geometry! Note that it is quite different than Euclidean geometry!
haha.. The space dimensions when square are negative! The time
dimension when squared is positive! 4-vectors built this way transform
under Lorentz transformations exactly. Since the dot product is a
scalar that transforms too!

People used to talk a lot about 'i' the imaginary number, but the
important thing to remember is that dot product of any two 4-vectors in
one frame is equal to their dot product in any other frame!

And we have a variable tau to replace time with in our discussion of
velocity!

In 3D space we have lim t-- >0 = delta r / delta t = dr/dt

In 4D spacetime we cannot divide by deta t because its not a scalar any
more! Its a vector! So, we substitute tau, which IS a scalar;

So, the 4-velocity u_ is given by (with all velocities in units of c)

u_ = lim tau-- > = delta f_ / delta tau = df_ /d tau
= (dt/dtau, dx/dtau, dy/dtau, dz/tau)
= (gamma, gamma Vx, gamma Vy, gamma Vz)

Now, we understand 4-velocity - now lets talk about its magnitude.

If we go to a frame where an object is at rest,with velocities in units
of c, then we can write its 4-velocity as;

u_ = (1,0,0,0)

and

Date: 16 Oct 2006 21:00:17
From: George Dishman
Subject: Re: infinite pill-shaped universe?

<William.Mook@gmail.com > wrote in message
news:1160922658.524284.136570@i42g2000cwa.googlegroups.com...
> George Dishman wrote:
>> <William.Mook@gmail.com> wrote in message
>> news:1160879786.993712.95180@k70g2000cwa.googlegroups.com...
>> > George Dishman wrote:
>> >> <William.Mook@gmail.com> wrote in message
>> >> news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...

<some background snipped to reduce the length >

>> > What we call rest mass is merely the projection of the mass-flux, or
>> > momentum into 3-space when the mass is not moving relative to the
>> > observer.
>>
>> Not quite, as I'm sure you know. AIUI, "momenergy"
>> (horrible word) is a 4-vector and when you project
>> that onto the 3 spatial axes you get the momentum.
>> Projecting it onto the time axis gives you the total
>> energy. Mass (*c^2) is the magnitude of the momenergy
>> so "rest mass" is the projection of momenergy onto
>> the worldline of the particle and kinetic energy is
>> the difference between that the total energy.
>
> Well, lets define terms a little - since that got us into trouble last
> time! haha... This is utterly called for when you use a technical
> term like 'momenergy' which neatly summarizes a few ideas folks have
> about spacetime! lol.
>
> momenergy doesn't have an archaic usage since it was made up in the
> last 50 years, and avoids the use of archaic terms like 'mass' which
> have deep connections with our life experience going back to the
> beginning of humanity.
>
> So, using definitions like this is appropriate in my view since its
> brand-new and useful! lol.
>
> Alright,what the hell is momenergy in 4-dimensiona spacetime? haha
>
> That's what I can see someone thinking who reads this.

Most of the people on the planet will never have heard
of the term and those who have probably know but let's
see what we can do for the lurkers.

> Well momentum is mass times velocity,

Nope. Care to try again ;-)

You see that's exactly the problem that arises from
working with "relativistic mass".

> and velocity is the differential
> of position with respect to time.

Yep, no problem there.

> Now, in 3D space time is a scalar.

Nope, in 3D space, time doesn't exist! Time is a
fourth axis perpendicular to the three spatial
axes, but you know that of course.

> In 4D spacetime it is a vector.

Nope, it is still an axis of a coordinate system.

> The problem is to create a sort of
> physics we are familiar with in 3D using our new 4D spacetime
> understanding of things. That means the results have to transform
> properly under Lorentzian transformations. How to do this?
>
> Time is a scalar in 3D space and can be easily transformed but time a
> vector in 4D spacetime and doesn't transform. So, we've got to figure
> out a scalar equivalent for time when physics is expressed in terms of
> a 4D vector. See?

No, I think you've got off on the wrong foot here. Time
is one of the coordinate axes (you're not talking about
'proper time' in this context).

> So, one way to do it is consider the length along the spacetime vector
> as an invariant.
>
> Well, recall that between any two events in space time there is a time
> interval (delta t) and three coordinate differences (space intervals)
> (delta x, delta y, delta z (assuming cartesian coordinates))
>
> So a four-vector a lot like a three-vector is built.
>
> f_ = (delta t, delta x, delta y, delta z)

What you have there is a finite interval between two
locations, and you can treat that as a displacement
vector but you need to be very careful not to confuse
it with a vector at the first location, such as the
four-velocity. The former tends to the latter in the
limit as the deltas become infinitessimal of course.

None of the above deltas are invariant, only tau as
you say next.

> There is an invariant scalar (tau) associated with each four-vector
> defined as;
>
> f_ dot f_ = (delta t)^2 - (delta x)^2 - (delta y)^2 - (delta z)^2 =
> tau ^2

> The nature of this dot products defines the nature of Lorentzian
> geometry!

Riemann geometry.

> Note that it is quite different than Euclidean geometry!
> haha.. The space dimensions when square are negative! The time
> dimension when squared is positive!

Or vice versa if you prefer.

> 4-vectors built this way transform
> under Lorentz transformations exactly. Since the dot product is a
> scalar that transforms too!

Since it is the magnitude of the vector, of course.

> People used to talk a lot about 'i' the imaginary number, but the
> important thing to remember is that dot product of any two 4-vectors in
> one frame is equal to their dot product in any other frame!
>
> And we have a variable tau to replace time with in our discussion of
> velocity!

No you don't.

> In 3D space we have lim t-->0 = delta r / delta t = dr/dt
>
> In 4D spacetime we cannot divide by deta t because its not a scalar any
> more! Its a vector!

Rubbish, your "delta t" is still a scalar and (dx/dt, dy/dt, dz/dt)
is still the velocity in that frame.

> So, we substitute tau, which IS a scalar;
>
> So, the 4-velocity u_ is given by (with all velocities in units of c)
>
> u_ = lim tau--> = delta f_ / delta tau = df_ /d tau
> = (dt/dtau, dx/dtau, dy/dtau, dz/tau)
> = (gamma, gamma Vx, gamma Vy, gamma Vz)
>
> Now, we understand 4-velocity - now lets talk about its magnitude.
>
> If we go to a frame where an object is at rest,with velocities in units
> of c, then we can write its 4-velocity as;
>
> u_ = (1,0,0,0)
>
> and
>
>

Date: 16 Oct 2006 18:02:22
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear George Dishman:

"George Dishman" <george@briar.demon.co.uk > wrote in message
news:eh0ngp$r73$1@news.freedom2surf.net...
...
>> Those mental constructs can arrive deeply from our being -
>> as in the hard wiring of our brain, and those mental
>> constructs can arrive by thought and practice, as in
>> learning relativity effects (something we don't deal with in
>> our personal experience on a regular basis) but useful in
>> describing high speed and high energy situations.
>
> That's absolutely on the button. the "3D plus time" view
> of the world has been structured into our brains by
> millions of years of evolution and it is actually quite
> hard to break free of it even though experiments have
> shown us it is a subset of the way the universe works.

I cannot agree that "3D plus time" is hardwired into our brains.
We have been taught to break problems down first into 1D, then
2D, with ever more complex "problems", since we were children.

We describe our current reality with the tools our "parents" gave
us... not the genes, but the experience. The tools that our
"parents" understand and are familiar with, limits our language
now

The "spatial wording" of primitive tribes is at most 1D + time.
Ask a young child why he did such and such a thing, and you get a
very quantum mechanical answer.

I submit the "millions of years" is simply the distance between
your now and your elementary education, from this "distant"
perspective. I'm not saying that it is wrong, just that the
"issue" is couched not in "hardwiring" but in "enculturation".

David A. Smith

Date: 21 Oct 2006 10:33:34
From: George Dishman
Subject: Re: infinite pill-shaped universe?

"N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com > wrote in
message news:sYVYg.4739$v43.1640@fed1read02...
> Dear George Dishman:
>
> "George Dishman" <george@briar.demon.co.uk> wrote in message
> news:eh0ngp$r73$1@news.freedom2surf.net...
> ...
>>> Those mental constructs can arrive deeply from our being -
>>> as in the hard wiring of our brain, and those mental
>>> constructs can arrive by thought and practice, as in
>>> learning relativity effects (something we don't deal with in
>>> our personal experience on a regular basis) but useful in
>>> describing high speed and high energy situations.
>>
>> That's absolutely on the button. the "3D plus time" view
>> of the world has been structured into our brains by
>> millions of years of evolution and it is actually quite
>> hard to break free of it even though experiments have
>> shown us it is a subset of the way the universe works.
>
> I cannot agree that "3D plus time" is hardwired into our brains. We have
> been taught to break problems down first into 1D, then 2D, with ever more
> complex "problems", since we were children.
>
> We describe our current reality with the tools our "parents" gave us...
> not the genes, but the experience. The tools that our "parents"
> understand and are familiar with, limits our language now
>
> The "spatial wording" of primitive tribes is at most 1D + time. Ask a
> young child why he did such and such a thing, and you get a very quantum
> mechanical answer.
>
> I submit the "millions of years" is simply the distance between your now
> and your elementary education, from this "distant" perspective. I'm not
> saying that it is wrong, just that the "issue" is couched not in
> "hardwiring" but in "enculturation".

I disagree. It is well known that newborn children
can bond with those they see in the first few weeks
of life and do that by recognising faces more than
anything else. They are not limited to only
recognising a face when pointed directly at them
and I'm sure you would not consider someone you knew
but seen side-on as a different person. Given a flat
2D photograph, our perception centres build a 3D
model and many "optical illusions" rely on that
function.

The idea that "We have been taught to break problems
down first into 1D ..." seems bizarre to me. I have
never been taught to recognise a face by first
converting it into a line.

George

Date: 21 Oct 2006 16:09:19
From: N:dlzc D:aol T:com $dlzc$
Subject: Re: infinite pill-shaped universe?

Dear George Dishman:

"George Dishman" <george@briar.demon.co.uk > wrote in message
news:ehcoo9$8ns$2@news.freedom2surf.net...
>
> "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com>
> wrote in message news:sYVYg.4739$v43.1640@fed1read02...
>> Dear George Dishman:
>>
>> "George Dishman" <george@briar.demon.co.uk> wrote in message
>> news:eh0ngp$r73$1@news.freedom2surf.net...
>> ...
>>>> Those mental constructs can arrive deeply from our being -
>>>> as in the hard wiring of our brain, and those mental
>>>> constructs can arrive by thought and practice, as in
>>>> learning relativity effects (something we don't deal with in
>>>> our personal experience on a regular basis) but useful in
>>>> describing high speed and high energy situations.
>>>
>>> That's absolutely on the button. the "3D plus time" view
>>> of the world has been structured into our brains by
>>> millions of years of evolution and it is actually quite
>>> hard to break free of it even though experiments have
>>> shown us it is a subset of the way the universe works.
>>
>> I cannot agree that "3D plus time" is hardwired into our
>> brains. We have been taught to break problems down
>> first into 1D, then 2D, with ever more complex
>> "problems", since we were children.
>>
>> We describe our current reality with the tools our
>> "parents" gave us... not the genes, but the
>> experience. The tools that our "parents"
>> understand and are familiar with, limits our language
>> now
>>
>> The "spatial wording" of primitive tribes is at most
>> 1D + time. Ask a young child why he did such and
>> such a thing, and you get a very quantum mechanical answer.
>>
>> I submit the "millions of years" is simply the
>> distance between your now and your elementary
>> education, from this "distant" perspective. I'm not saying
>> that it is wrong, just that the "issue" is
>> couched not in "hardwiring" but in "enculturation".
>
> I disagree. It is well known that newborn children
> can bond with those they see in the first few weeks
> of life and do that by recognising faces more than
> anything else. They are not limited to only
> recognising a face when pointed directly at them
> and I'm sure you would not consider someone you
> knew but seen side-on as a different person. Given
> a flat 2D photograph, our perception centres build
> a 3D model and many "optical illusions" rely on
> that function.

Pattern matching, and "revolving" or "expanding" a pattern into a
known form is a miracle, but isn't really more than 2D.

> The idea that "We have been taught to break problems
> down first into 1D ..." seems bizarre to me. I have
> never been taught to recognise a face by first
> converting it into a line.

Recall early "grade" school, when you were taught first to
measure distance, then later when change-in-time was applied to
arrive at speed.

But I get your point. Og the caveman had to know how to
anticipate the future position of the antelope, in order to
arrange to have a spear meet it there. The fact that this skill
exists even in frogs and "spitting fish" attests to the millions
of years of evolution. I guess I can agree, if the 3D is
"spherical coordinates"... ; >)

David A. Smith

Date: 17 Oct 2006 11:55:20
From: oriel36
Subject: Re: infinite pill-shaped universe?

George Dishman wrote:
> <William.Mook@gmail.com> wrote in message
> news:1160922658.524284.136570@i42g2000cwa.googlegroups.com...
> > George Dishman wrote:
> >> <William.Mook@gmail.com> wrote in message
> >> news:1160879786.993712.95180@k70g2000cwa.googlegroups.com...
> >> > George Dishman wrote:
> >> >> <William.Mook@gmail.com> wrote in message
> >> >> news:1160657016.534178.286930@m7g2000cwm.googlegroups.com...
>
> <some background snipped to reduce the length>
>
> >> > What we call rest mass is merely the projection of the mass-flux, or
> >> > momentum into 3-space when the mass is not moving relative to the
> >> > observer.
> >>
> >> Not quite, as I'm sure you know. AIUI, "momenergy"
> >> (horrible word) is a 4-vector and when you project
> >> that onto the 3 spatial axes you get the momentum.
> >> Projecting it onto the time axis gives you the total
> >> energy. Mass (*c^2) is the magnitude of the momenergy
> >> so "rest mass" is the projection of momenergy onto
> >> the worldline of the particle and kinetic energy is
> >> the difference between that the total energy.
> >
> > Well, lets define terms a little - since that got us into trouble last
> > time! haha... This is utterly called for when you use a technical
> > term like 'momenergy' which neatly summarizes a few ideas folks have
> > about spacetime! lol.
> >
> > momenergy doesn't have an archaic usage since it was made up in the
> > last 50 years, and avoids the use of archaic terms like 'mass' which
> > have deep connections with our life experience going back to the
> > beginning of humanity.
> >
> > So, using definitions like this is appropriate in my view since its
> > brand-new and useful! lol.
> >
> > Alright,what the hell is momenergy in 4-dimensiona spacetime? haha
> >
> > That's what I can see someone thinking who reads this.
>
> Most of the people on the planet will never have heard
> of the term and those who have probably know but let's
> see what we can do for the lurkers.
>
> > Well momentum is mass times velocity,
>
> Nope. Care to try again ;-)
>
> You see that's exactly the problem that arises from
> working with "relativistic mass".
>
> > and velocity is the differential
> > of position with respect to time.
>
> Yep, no problem there.
>
> > Now, in 3D space time is a scalar.
>
> Nope, in 3D space, time doesn't exist! Time is a
> fourth axis perpendicular to the three spatial
> axes, but you know that of course.
>

Do you know where this idea comes from ? -

'It is simply this. That Space, as our mathematicians have it, is
spoken of as having three dimensions, which one may call Length,
Breadth, and Thickness, and is always definable by reference to three
planes, each at right angles to the others. But some philosophical
people have been asking why three dimensions particularly-why not
another direction at right angles to the other three?-and have even
tried to construct a Four-Dimension geometry. Professor Simon Newcomb
was expounding this to the New York Mathematical Society only a month
or so ago. You know how on a flat surface, which has only two
dimensions, we can represent a figure of a three-dimensional solid, and
similarly they think that by models of thee dimensions they could
represent one of four-if they could master the perspective of the
thing. See?'"

You could find that idea in any section fiction section of a bookshop
back in 1898,you can actually find it on the internet -

http://www.bartelby.com/1000/1.html

Somebody is supposed to be embarrassed or be wide-eyed that a fictional
novel is the basis for astronomy or what our eyes see when we look out
on the magnificence of the celestial arena.

The narrative neccessity of Wells is fine,the belief that somebody
found it possible is not.At the core of it all is celestial sphere
geometry as its supplied the foundations for the false Newtonian
conceptions.

> > In 4D spacetime it is a vector.
>
> Nope, it is still an axis of a coordinate system.
>
> > The problem is to create a sort of
> > physics we are familiar with in 3D using our new 4D spacetime
> > understanding of things. That means the results have to transform
> > properly under Lorentzian transformations. How to do this?
> >
> > Time is a scalar in 3D space and can be easily transformed but time a
> > vector in 4D spacetime and doesn't transform. So, we've got to figure
> > out a scalar equivalent for time when physics is expressed in terms of
> > a 4D vector. See?
>
> No, I think you've got off on the wrong foot here. Time
> is one of the coordinate axes (you're not talking about
> 'proper time' in this context).
>
> > So, one way to do it is consider the length along the spacetime vector
> > as an invariant.
> >
> > Well, recall that between any two events in space time there is a time
> > interval (delta t) and three coordinate differences (space intervals)
> > (delta x, delta y, delta z (assuming cartesian coordinates))
> >
> > So a four-vector a lot like a three-vector is built.
> >
> > f_ = (delta t, delta x, delta y, delta z)
>
> What you have there is a finite interval between two
> locations, and you can treat that as a displacement
> vector but you need to be very careful not to confuse
> it with a vector at the first location, such as the
> four-velocity. The former tends to the latter in the
> limit as the deltas become infinitessimal of course.
>
> None of the above deltas are invariant, only tau as
> you say next.
>
> > There is an invariant scalar (tau) associated with each four-vector
> > defined as;
> >
> > f_ dot f_ = (delta t)^2 - (delta x)^2 - (delta y)^2 - (delta z)^2 =
> > tau ^2
>
>
> > The nature of this dot products defines the nature of Lorentzian
> > geometry!
>
> Riemann geometry.
>
> > Note that it is quite different than Euclidean geometry!
> > haha.. The space dimensions when square are negative! The time
> > dimension when squared is positive!
>
> Or vice versa if you prefer.
>
> > 4-vectors built this way transform
> > under Lorentz transformations exactly. Since the dot product is a
> > scalar that transforms too!
>
> Since it is the magnitude of the vector, of course.
>
> > People used to talk a lot about 'i' the imaginary number, but the
> > important thing to remember is that dot product of any two 4-vectors in
> > one frame is equal to their dot product in any other frame!
> >
> > And we have a variable tau to replace time with in our discussion of
> > velocity!
>
> No you don't.
>
> > In 3D space we have lim t-->0 = delta r / delta t = dr/dt
> >
> > In 4D spacetime we cannot divide by deta t because its not a scalar any
> > more! Its a vector!
>
> Rubbish, your "delta t" is still a scalar and (dx/dt, dy/dt, dz/dt)
> is still the velocity in that frame.
>
> > So, we substitute tau, which IS a scalar;
> >
> > So, the 4-velocity u_ is given by (with all velocities in units of c)
> >
> > u_ = lim tau--> = delta f_ / delta tau = df_ /d tau
> > = (dt/dtau, dx/dtau, dy/dtau, dz/tau)
> > = (gamma, gamma Vx, gamma Vy, gamma Vz)
> >
> > Now, we understand 4-velocity - now lets talk about its magnitude.
> >
> > If we go to a frame where an object is at rest,with velocities in units
> > of c, then we can write its 4-velocity as;
> >
> > u_ = (1,0,0,0)
> >
> > and
> >
> >

Date: 24 Oct 2006 06:21:46
From:
Subject: Re: infinite pill-shaped universe?

Whats this about an infinite universe

On 9, 4:19=A0pm, "Hagar" <h...@sahm.name > wrote:
> "Liam" <n...@celticbear.com> wrote in messagenews:1160423445.892101.40190=
@m7g2000cwm.googlegroups.com...
>
>
>
>
>
> > Just found this CNN article where measured cosmic radioactivity seems
> > to indicate the universe is pill-shaped:
> >http://www.cnn.com/2006/TECH/space/10/09/universe.pill/index.html
>
> > Now, I've just come to grips with the concept of the universe being
> > infinite and expanding out of a Big...Expanding like "raisin bread" or
> > an infinitely thick skin of a balloon.
>
> > Now this pill-shaped thing? I can't reconcile this in my mind.
>
> > Could someone help me understand how both of these can be true, or
> > whether one theory undermines the other?
>
> > Thanks!
> > LiamWhat if the early Universe had an axial spin to it and with that sp=
in, it
> had developed a slight equatorial bulge, pretty much like Earth has. =A0N=
ow if
> that spin were to slow down over time, could it create the opposite of a,
> equatorial bulge, something like an equatorial waist, which would give it=
a
> pill-shaped, somewhat oblong appearance, or would it still remain a sphere
> ??- Hide quoted text -- Show quoted text -

Date: 26 Oct 2006 18:43:27
From: Mike
Subject: infinite pill-shaped universe?

<Havriliak@aol.com > wrote in message
news:1161696106.442517.38430@m7g2000cwm.googlegroups.com...
Whats this about an infinite universe

LOL..exactly!...the description negates the other. If it's infinite it
can't have a shape!!