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  #21  
Old September 6th 03, 10:48 PM
G=EMC^2 Glazier
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Hi oc and Painius I think of Galactic Space using the lyrics of Ira
Gershwin's song "I've got plenty of nothing,and nothing is plenty for
me' fits(Porgy& Bess) Strange as it might sound man has to come to an
understanding of "nothing" The reason for that is there will always be
a smart ass saying "from Where does this cometh? I say it came from
gravity compressing energy of space,and he knocks me down with where did
the space energy come from,and buries me with where did this force of
gravity come from. I hate smart asses Bert

  #22  
Old September 7th 03, 12:12 AM
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G=EMC^2 Glazier wrote:
What if the universe is infinitely big. That could be the reason the
Earth looks like its in the middle of it. Than every where can look like
its in the middle. Everything would look the same in every direction. If
we can think infinitely dense,as taking up no space, Than why can't we
think the universe is taking up all the space in the world. I think it
is infinitely better think. Bert


What if EVERY place in the universe is in the center and if you
were to travel far enough into deep space in ANY direction,
you'd end up back where you began?

Bjacoby

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  #24  
Old September 7th 03, 02:51 PM
G=EMC^2 Glazier
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Bjacoby That is true light curves and could conceivable circle back to
its source. This does not mean the universe has to be finite. If are
great telescopes see no stars in any direction that does not mean they
came to the edge of the universe. Theories have when we can come to the
first 300,000 years of the BB it should be all photons. Bert

  #25  
Old September 7th 03, 04:28 PM
atrso@nospam-[roteus.demon.co.uk
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On Sun, 7 Sep 2003 15:57:35 +0200, "username" e-mail@adress wrote:


you misunderstood my posting. I was saying that it is fundamentally
impossible to answer you "what if" question, it is NOT comparable to the
question "what if the earth is round".

Sorry for the misunderstanding, but the premise still applies, if
people hadn't asked "what if2 about the world being flat, then for all
we could know today, the world could be flat.
Try not to think in terms of specifics, IE don't look at the whole
question, look at the asking of the question.

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The two most abundant elements in the universe are Hydrogen and stupidity.
Why is the ratio of Hydrogen to Stupidity less in usenet than anywhere else in the universe?
  #26  
Old September 7th 03, 04:41 PM
username
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wrote in message
...
On Sun, 7 Sep 2003 15:57:35 +0200, "username" e-mail@adress wrote:


you misunderstood my posting. I was saying that it is fundamentally
impossible to answer you "what if" question, it is NOT comparable to the
question "what if the earth is round".

Sorry for the misunderstanding, but the premise still applies, if
people hadn't asked "what if2 about the world being flat, then for all
we could know today, the world could be flat.
Try not to think in terms of specifics, IE don't look at the whole
question, look at the asking of the question.


but you are talking about a different types of "question". Your example
refers to a sound scientific question, but the whatif question you pose is
not sound, hence answering it is not useful.



  #27  
Old September 7th 03, 08:41 PM
Dennis Taylor
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"Bill Sheppard" wrote in message
...
Steve@nospam wrote,
A good example is the bedrock axiom that holds the speed of light to be
constant all the way to the limit of visibility.. with the presumption
that it is also constant all the way to the BB itself. The doctrine of
universal c-invariance, of course, is rooted in void-space, that is, the
premise that space is functionally void or 'nothing'.


One of the unstated assumptions, when people come up with these more "out
there" speculations, is the assumption that you can change one rule or law
or constant (such as C in this case) and everything else will operate as
before, except light will travel at a different speed. Or there's the
creationist proposal that radioactive dating is flawed because radioactive
decay rates used to be different that they are now.

The trouble with these ideas is the implications involved in changing basic
constants. For instance, changing C changes the results that you get from
e=mc^2, which means (among other things) that the amount of energy that a
star gets from fusing hydrogen to form helium will change. This means that
the whole "main sequence" chart for types of stars would be different, and
the difference would be detectable. In the real world, however, stars 5
billion light years away look just like the ones next door.

In the case of the radioactive decay change, that would require a change in
the strong nuclear force. Among other problems, this would also change
stellar fusion behaviour. It's been stated by cosmologists that the physical
laws of the universe are so finely tuned that even a small change would
result in a universe incapable of supporting life or even stars.

Getting back to Bill's speculation, while there's certainly nothing wrong
with proposing "way out" ideas, the onus is always on the person proposing
an alternative to mainstream beliefs to come up with reasons why we should
take them seriously. At minimum, the new theory must explain existing
observations as well as the existing theory; in addition, it must also
either explain some observation that the existing theory can't, or it must
make a prediction that can be checked which wouldn't follow from the
existing theory. If it doesn't do these things, then really the only
reasonable reaction is "Uh huh. So?"







  #28  
Old September 7th 03, 09:04 PM
username
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"Dennis Taylor" wrote in message
. ca...
"Bill Sheppard" wrote in message
...
Steve@nospam wrote,
A good example is the bedrock axiom that holds the speed of light to be
constant all the way to the limit of visibility.. with the presumption
that it is also constant all the way to the BB itself. The doctrine of
universal c-invariance, of course, is rooted in void-space, that is, the
premise that space is functionally void or 'nothing'.


One of the unstated assumptions, when people come up with these more "out
there" speculations, is the assumption that you can change one rule or law
or constant (such as C in this case) and everything else will operate as
before, except light will travel at a different speed. Or there's the
creationist proposal that radioactive dating is flawed because radioactive
decay rates used to be different that they are now.

The trouble with these ideas is the implications involved in changing

basic
constants. For instance, changing C changes the results that you get from
e=mc^2, which means (among other things) that the amount of energy that a
star gets from fusing hydrogen to form helium will change. This means that
the whole "main sequence" chart for types of stars would be different, and
the difference would be detectable. In the real world, however, stars 5
billion light years away look just like the ones next door.

In the case of the radioactive decay change, that would require a change

in
the strong nuclear force. Among other problems, this would also change
stellar fusion behaviour. It's been stated by cosmologists that the

physical
laws of the universe are so finely tuned that even a small change would
result in a universe incapable of supporting life or even stars.

Getting back to Bill's speculation, while there's certainly nothing wrong
with proposing "way out" ideas, the onus is always on the person proposing
an alternative to mainstream beliefs to come up with reasons why we should
take them seriously. At minimum, the new theory must explain existing
observations as well as the existing theory; in addition, it must also
either explain some observation that the existing theory can't, or it must
make a prediction that can be checked which wouldn't follow from the
existing theory. If it doesn't do these things, then really the only
reasonable reaction is "Uh huh. So?"


very well said, thank you!


  #29  
Old September 8th 03, 01:25 AM
Bill Sheppard
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Jonathan S. wrote,

Good point, but is Bill (or anyone else)
suggesting that the speed of light has
varied since the universe became the
way we see it now?


Yes. As was posted previously in this thread and numerous threads
before, some credentialed 'mainstreamers' (not just loonytooners) are
indeed questioning universal c-invariance. Again, see-
http://ldolphin.org/setterfield/earlycosmos.html
Also see-
www.Lns.cornell.edu/spr/1999-11/msg0019253.html
http://www.ldolphin.org/troitskii and
www.sciencenews.org/20011006/bob16.asp
Though their models differ superficially, these guys
are proposing a gradual c-drop across the age of the observable
universe.

What happens if it only varies during the
first 300,000 years, when the universe is
unobservable and problems like the
stability of stars are irrelevant? That time changes, and conditions

in that time
change, but does anything else?


As was posted previously in this thread and numerous times before,
'mainstreamers' Drs. Joao Magueijo and Andy Albrecht (Albrecht was one
of the founders of inflation theory) have proposed the VSL (variable
speed of light) model as an alternative to inflation. Basically, their
model has a very precipititous c-drop across the 'inflation' spike,
completely eliminating the need for inflation. Again, see-
http://theory.ic.ac.uk/~magueijo/vsl.html
A quick web search under 'Magueijo-Albrecht VSL' will turn up many
more hits on this model. By eliminating inflation, their VSL solves the
horizon problem while 'magically' eliminating inflation's niggling
problems such as the flatness paradox and the 'first Doppler peak'.
Their model has c dropping almost instantaneously to its present value,
unlike the more-gradual drop proposed by the other guys. And they
likewise believe it's necessary to violate the Lorentz invariance in
order to have a c-drop. It is **NOT** necessary to violate the Lorentz
invariance, and here's why:

Here's the kicker- as stated previously in this thread and numerous
times before, ALL these guys, Magueijo-Albrecht, Barrow, Moffatt, and
Troitskii, are still operating in the void-space regime. They are not
connecting their proposed c-drop to a *density gradient* in the spatial
medium of the expanding universe.

To re-quote an earlier post in this thread, Dennis Taylor wrote,

One of the unstated assumptions..... is
that you can change one rule or law or
constant (such as C in this case) and
everything else will operate as before,
except light will travel at a different
speed.... The trouble with this is the
implications involved in in changng basic
constants. For instance, changing C
changes the results you get from
E=mc^2, which means among other
things that the energy a star gets from
fusing hydrogen to helium will change.
This means the whole "main sequence"
chart for types of stars will be different,
and the difference will be detectable.

To which the oc said:
Yes Dennis, all that you state is absolutely true under
the void-space regime, that is, the premise that space is a functional
void or 'nothingness' all the way to the limit of visibility and thence
back to the BB itself. Under void-space, you cannot change c without
violating the other constants, as you state.
But the point you're missing (the 'kicker') is- if
space, far from being "nothing", is an expansible, compressible fluid,
it will display a *densty gradient* aross the expansion of the
universe.. and the speed of light will drop with the thinning of the
spatial medium (as by analogy the speed of sound in air drops with
thinning air density ^altitude). The greatest density-drop (and geatest
c-drop) will occur immediately following the BB, leveling out on a log
curve to the present value. *Some* of this density-gradient c-drop will
appear in the most ancient light visible to us, rendering that light
"dimmer than it should be" at a given redshift, just as is observed in
the recent 1a supernova data.
C is always constant *locally*, in the absence of a
density-gradient in the spatial medium. And all the other constants are
likewise fixed, locally. "Local" in this case applies out to a few
billion LY, where the density-gradient remains negligible, c remains
(nearly) constant, space can be treated _as if_ it were a void, and
relativity 'works' acceptably well out to these distances. At greater
distances the spatial density and c begin climbing exponentially.
There in that denser space, lightspeed is constant
locally, just as lightspeed is constant here, locally. In that denser
space, all constants INCLUDING THE LORENTZ INVARIANCE are fixed, just as
they are fixed here, locally. The prime variable from location to
location in the universe is spatial density. The relative value of c
varies with space density. Light propagating from denser space into
'our' less-dense space loses amplitude (brightness) due to the
*relative* drop in c between the two locations.

In the real world however, stars 5 billion LY away look just like the

ones next
door.


Yes at 5 BLY they look the same. At 10+ BLY they still "look" the same,
with the exception of being 'dimmer than they should be', due to c-drop.

But then, if space is functionally void, none of the foregoing applies.
We are stuck with a 'one-shot' BB, ever-accelerating expansion of the
"nothing", universal c-invariance, and an open-ended entropic rundown
back to 'nothing'.
oc

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  #30  
Old September 8th 03, 01:47 PM
Bill Sheppard
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Painius mused,

"But isn't space just SPACE? Isn't space
a VOID???"

"Er, uhm..."

"Isn't that why they call it SPACE?
Because it's VOID?"

"Well, uhm, there IS sort of... uhm... an
.'Energy Density' to space, and THAT'S
what's expanding. Yup, the energy
density."
"RIIIIiiiight."


Hey I betcha Moby could cast some light on the subject. Bert, run this
by Moby--

'Way down in the deep ocean there's an octopus who's going around
proposing a heretical theory to the orher octopii. He says they live in
something called the "ocean". They argue back, saying "Baloney. We live
in a void, see? This 'ocean' you speak of cannot be quantified,
isolated, or revealed by our senses. Therefore your 'ocean' is
nothingness and void."
The smarty-pants octopus says, "Our senses have evolved
to be 'blind' to the enormous hydrodynamic pressure of the ocean, and
that's why we _perceive_ it to be a void. But we can still deduce its
existance by observing its effects. In it we live and have our being. We
move by shooting jets of it. We know it resists acceleration thru it,
and supports currents. We know the ocean exists by what it does, even
though we are sensorally 'blind' to its pressure."

Let's see what Moby has to say about this analogy of the ocean
representing the Spatial Medium and its enormous vacuum energy density
(or VED).. our modern-day 'pneuma'.
oc

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