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Author Topic:   The infinite space of the Universe
lyx2no
Member (Idle past 2792 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 376 of 380 (470681)
06-11-2008 9:56 PM
Reply to: Message 374 by New Cat's Eye
06-11-2008 5:15 PM


Talking About Me in the Third Person, Ouch!
Actually this one.

http://space.newscientist.com/article/mg19826591.500


Kindly

∞∞∞∞∞∞∞

There is a spider by the water pipe.


This message is a reply to:
 Message 374 by New Cat's Eye, posted 06-11-2008 5:15 PM New Cat's Eye has not yet responded

Libmr2bs
Member (Idle past 3803 days)
Posts: 45
Joined: 05-15-2008


Message 377 of 380 (470690)
06-11-2008 10:57 PM
Reply to: Message 336 by lyx2no
06-10-2008 12:31 AM


Re: The Infinite Space Of The Universe
Spheres are man made. There is no such thing as a sphere in the natural universe. So why should the universe be a sphere? The only reason that I can think why people would visualize the universe as a sphere is that they can't accept the fact that the universe responds to chaotic interaction of matter and energies. When reality and theory collide, I bet on reality.
This message is a reply to:
 Message 336 by lyx2no, posted 06-10-2008 12:31 AM lyx2no has responded

Replies to this message:
 Message 378 by lyx2no, posted 06-11-2008 11:59 PM Libmr2bs has not yet responded

lyx2no
Member (Idle past 2792 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 378 of 380 (470696)
06-11-2008 11:59 PM
Reply to: Message 377 by Libmr2bs
06-11-2008 10:57 PM


Lovely, Little Cloud
It is known that space is warped by its mass/energy. If the mass/energy is sufficiently dense space will curve back on itself. If the mass/energy is sufficiently smooth it will curve back on itself evenly. In the model generally under discussion it is assumed — assumed in the model; not in the Universe — that the density and smoothness are sufficient. A closed, smooth, even 3-D curve is called the surface of a hyper sphere.

By way of analogy I used a closed, smooth, even 2-D curve called the surface of a sphere because it is easier to grasp. As has been mentioned, the parts of a model that are not being explained need not be incorporated into the analogy.

The fluffy, little cloud out side my office window is made of trillions of teeny-tiny, nearly perfect spheres. Thanks to you I now know it’s man made. Must be nice men who made that nice cloud.


Kindly

∞∞∞∞∞∞∞

There is a spider by the water pipe.


This message is a reply to:
 Message 377 by Libmr2bs, posted 06-11-2008 10:57 PM Libmr2bs has not yet responded

ICANT
Member
Posts: 6187
From: SSC
Joined: 03-12-2007


Message 379 of 380 (470704)
06-12-2008 12:59 AM
Reply to: Message 371 by Straggler
06-11-2008 1:08 PM


Re: What problems
Straggler writes:

Really? What problems are these?

How about these for starters?

The flatness problem.
The horizon problem.
The monopole problem.

CAMBRIDGE COSMOLOGY lists the following.
http://www.damtp.cam.ac.uk/user/gr/public/bb_problems.html

The flatness problem
Why is the matter density of the universe so close to the unstable critical value between perpetual expansion and recollapse into a Big Crunch?

The horizon problem
Why does the universe look the same in all directions when it arises out of causally disconnected regions? This problem is most acute for the very smooth cosmic microwave background radiation.

The density fluctuation problem
The perturbations which gravitationally collapsed to form galaxies must have been primordial in origin; from whence did they arise?

The thermal state problem
Why should the universe begin in thermal equilibrium when there is no mechanism by which it can be maintained at very high temperatures.

The cosmological constant problem
Why is the cosmological constant 120 orders of magnitude smaller than naively expected from quantum gravity?

The singularity problem
The cosmological singularity at t=0 is an infinite energy density state, so general relativity predicts its own breakdown.

The timescale problem
Are independent measurements of the age of the Universe consistent using Hubble's constant and stellar lifetimes?

In AN INTRODUCTION TO COSMOLOGICAL INFLATION
ANDREW R. LIDDLE put forth:

3. Problems with the Big Bang
3.1. The flatness problem
3.2. The horizon problem
3.3. The monopole problem (and other relics)

4.
4.1 Inflation solves the flatness problem more or less by definition.
4.2 The rapid expansion of the inflationary stage rapidly dilutes the unwanted
relic particles,
4.3 The inflationary expansion also solves the horizon problem.

In summary Liddle said:

At present, inflation is the most promising candidate theory for the origin
of perturbations in the Universe. Different inflation models lead to discernibly
different predictions for these perturbations, and hence high-accuracy measurements
are able to distinguish between models, excluding either all or the
vast majority of them.
Since its inception, the inflationary cosmology has been a gallery of different
models, and the gallery has continually needed extension after extension
to house new acquisitions. In all the time up to the present, very few models
have been discarded.

http://arxiv.org/PS_cache/astro-ph/pdf/9901/9901124v1.pdf

Guth in his paper ETERNAL INFLATION said:

Guth's first evidence for inflation is that there is so much mass in the universe. 1090 particles in the visible region. The only way to get that is if the mass doubles a few hundred times.

Guth's second evidence is expansion itself.

Guth's third evidence for inflation is that it is the only theory known that can explain the homogeneity and isotropy of the universe.

Guth writes:

In the standard big bang theory there is no explanation whatever for this uniformity. In fact, one can even show that within the context of the standard big bang theory, no explanation for this uniformity is possible.

Guth's fourth evidence is the flatness problem. Critical density.

Guth's fifth evidence becomes a reason for believing. So now he has FIVE REASONS FOR BELIEVING IN THE INFLATION THEORY.

The fifth reason for believing the inflationary description is the absence of magnetic monopoles.

This is the 2001 version not the original.

For the explicit constructions of eternally inflating models, the answer is clear. Such models start with a state in which there are no pocket universes at all, just pure repulsivegravity material filling space. So there is definitely a beginning to the models that we know how to construct.

I like this one he starts out with space filled with repulsivegravity material. I wonder where all that space and material came from.

http://arxiv.org/abs/astro-ph/0101507

According to Cambridge Cosmology there are many problems with the standard BBT.

According to Liddel there are several problems with the standard BBT.

According to Guth there are several problems with the standard BBT.

According to Liddel and Guth Inflation solves all the problems.

Now if there was just some way to get evidence that inflation happened.

But then you would need evidence of where the space came from.

Then you would need evidence of where the repulsivegravity matter that was in the space came from.

Then you would need evidence for where the positive matter that reacted with the repulsive matter came from.

There are many hypothesis of inflation but none have reached the point of theory even though they are called a theory.

Now if you have information that refutes what these gentlemen say I would be interested in reading it.

Straggler writes:

I am still not sure why you think any of this is a hige problem for BB theory?

Guth, Liddel and Cambridge Cosmology think there is a problem.
They are much more qualified than I am to determine if there is a problem or not.

Straggler writes:

Or do you fear that if you read a convincing book on the subject you might be tempted over to the dark side........? ;)

Why would I want to read one persons opinion. I would much rather read what Stephen Hawking, Alan Guth , Andrew R. Liddle ,Robert H. Brandenberger, Sean M. Carroll, Arthur Kosowsky among many others have to say.

Straggler writes:

COBE, WMAP etc. have since largely verified inflatiionary theory and it is now part of the established BB model.

Not that I don't trust you but I need a little more than an assertion that the inflationary theory is largly verified.

I found the statement below and can not find one that says it is verified.

Michael S. Turner (U. Chicago and Fermilab) made this comment in his paper The New Cosmology Mid-Term Report Card for Inflation.
http://arxiv.org/abs/astro-ph/0212281

While inflation has by no means been verified, its successes have raised the bar for competitor theories:

God Bless,


"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."
This message is a reply to:
 Message 371 by Straggler, posted 06-11-2008 1:08 PM Straggler has not yet responded

Replies to this message:
 Message 380 by Adminnemooseus, posted 06-12-2008 1:22 AM ICANT has not yet responded

  
Adminnemooseus
Director
Posts: 3879
Joined: 09-26-2002


Message 380 of 380 (470710)
06-12-2008 1:22 AM
Reply to: Message 379 by ICANT
06-12-2008 12:59 AM


Seems overblown for a single message, but...
this seems to be some interesting stuff (says the admin who hasn't much been following this topic) that looks to be in the position of getting buried in an already bloated topic.

I'm going to close this one down. I suggest you submit a more concise and better written version of your message as a proposed new topic.

Please come up with a concise central theme and a corresponding topic title.

Adminnemooseus


This message is a reply to:
 Message 379 by ICANT, posted 06-12-2008 12:59 AM ICANT has not yet responded

  
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