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Science Section => Science General Discussion => Physics & Cosmology => Topic started by: josephpalazzo on July 19, 2013, 09:32:19 PM

Title: A Universe without expansion
Post by: josephpalazzo on July 19, 2013, 09:32:19 PM
A different cosmology in which the Universe is not expanding but the mass of everything has been increasing. If true, those who have banked on the BBT for whatever reasons will have to swallow their pride. However, let's not rush to judgment. But this is indeed interesting.

QuoteWe discuss a cosmological model where the universe shrinks rather than expands during the radiation and matter dominated periods. Instead, the Planck mass and all particle masses grow exponentially. Together with a preceding inflationary phase and a late dark energy dominated epoch this model is compatible with all observations. The curvature is almost constant during all epochs. Cosmology has no big bang singularity. There exist other, equivalent choices of field variables for which the universe shows the usual expansion or is static during the radiation or matter dominated epochs. For those ``field coordinates`` the big bang is singular. Thus the big bang singularity turns out to be related to a singular choice of field coordinates.

http://arxiv.org/pdf/1303.6878v2.pdf (http://arxiv.org/pdf/1303.6878v2.pdf)
Title: Re: A Universe without expansion
Post by: FrankDK on July 19, 2013, 09:42:35 PM
I have occasionally wondered if the universe, on the largest scale, hasn't always looked essentially the way it now does.  What if there really is a cosmological constant that keeps the universe essentially static, but alters photons over long distances so they appear to be red-shifted.  The further they travel, the more red-shifted they look.  But the distance between distant galaxies and the Milky Way might not be changing at all.  The universe could be infinitely large and infinitely old.

Frank
Title: Re: A Universe without expansion
Post by: Solitary on July 19, 2013, 11:47:03 PM
Thanks! I'm very interested in the latest information on the universe.

I have question the singularity because the laws of physics breaks down in one with Einstein's  relativity and is answered with quantum physics. As to the creation from nothing and expanding ever faster doesn't seem rational, and is too much like religious ideas of Creation. Also, there is a lot of evidence that contradicts the Big Bang that is ignored, suppressed, or answered Ad Hoc. I think instead of infinite or eternal it should be finite but unbounded, and just is with no beginning or end and just is, with unending change. But as always, just my opinion, or else. Solitary










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Title: Re: A Universe without expansion
Post by: Jason78 on July 20, 2013, 05:09:03 AM
4 Pages!

I'll read it and get back to you.
Title: Re: A Universe without expansion
Post by: Plu on July 20, 2013, 06:02:48 AM
That sounds pretty interesting. Always nice to see science going forward :)
Title: Re: A Universe without expansion
Post by: SGOS on July 20, 2013, 06:39:11 AM
Not being a cosmologist, the idea makes a kind of sense to me.  I doubt that Big Bang enthusiasts are likely to have their egos bashed too much if this turned out to be true.  Most would just accept the new theory if it were supported by observable facts.  And they wouldn't have to give up the idea of the Big Bang either, because an infinite increase in mass might eventually lead to another singularity.

In any case, science is not about holding onto antiquated theory.  That's what religions do.  Science is dynamic and changing, not a static dogma.
Title: Re: A Universe without expansion
Post by: aitm on July 20, 2013, 09:33:09 AM
can you explain that using crayons and marbles?
Title: Re: A Universe without expansion
Post by: Seabear on July 20, 2013, 10:18:02 AM
JP, how does this theory explain the presence of cosmic background radiation?
Title: Re: A Universe without expansion
Post by: Colanth on July 20, 2013, 04:27:29 PM
Quote from: "Solitary"I think instead of infinite or eternal it should be finite but unbounded
Not a new idea.  //http://www.bartleby.com/173/31.html
Title: Re: A Universe without expansion
Post by: stromboli on July 20, 2013, 04:32:24 PM
Quote from: "aitm"can you explain that using crayons and marbles?

I don't even understand non-Euclidean geometry.  :(

Like, I barely passed Geometry and then they went all non-Euclidean on me. I'm sad right now.
Title: Re: A Universe without expansion
Post by: SGOS on July 20, 2013, 07:16:24 PM
I took plane geometry in high school as a sophomore.  I don't think we figured out the area of a single rectangle or a circle.  It was nothing but theorems and proofs:

A is something or other,
B is something else,
This axiom says whatever,
Therefore, C is must be thus and so.

It was a lot of fun.  Not a single bit of arithmetic during the entire year.  One time, a grownup asked me if it was "Euclidian" (actually, I can't remember what he called it) geometry or some other kind of geometry.  I didn't know so I explained it to him, and he looked like he puzzled over it, and then said something like, "Well that sounds like it's [can't remember what he said] geometry."  

I really liked that course.  It reminded me of logic, although I had never heard of formal logic at the time.  Every proof starts with some assumption or something already proven, and after a number of statements, it would lead to a conclusion that something was always a right angle, or A and B were equal, or something similar.  Does this sound familiar to anyone?

College trig was something like that, but I struggled with it, and managed to get a C.  I thought I was going to fail it for a while.
Title: Re: A Universe without expansion
Post by: Satt on July 20, 2013, 08:26:42 PM
It kills me how religions can believe in a god who has no beginning, but can't imagine the universe not having one.
Title: Re: A Universe without expansion
Post by: Hakurei Reimu on July 20, 2013, 10:21:30 PM
What bothers me about this paper is that it lends no discussion at all of how scaling the masses of all particles in the Standard Model in step actually just adjusts the atomic spectra up and down the spectrum.

If you change any other parameter in the Standard Model, you get effects all over the place. That's how we are able to tell that the Standard Model has to be adjusted to those parameters and not others. It's a known problem that plagues other "theories" that propose variations in other constants in the Standard Model — if you change a bunch of constants, you see other things that should happen when you look that deep into space, and not just the effect you're after. But this one seems to just has atomic spectra being affected. Really? This is the only thing that happens if you change all these parameters in step?

I'm very... suspicious that in the paper this problem is just swept under the rug.
Title: Re: A Universe without expansion
Post by: Plu on July 21, 2013, 04:20:25 AM
QuoteI really liked that course. It reminded me of logic, although I had never heard of formal logic at the time. Every proof starts with some assumption or something already proven, and after a number of statements, it would lead to a conclusion that something was always a right angle, or A and B were equal, or something similar. Does this sound familiar to anyone?

We had a module on this subject in mathematics as well. Fascinating stuff, but pretty hard. And the simpler the thing you had to prove, the harder it got. Really weird. At some point we had to prove that all the corners in a square are 90 degrees and we couldn't for the life of us figure it out. But that was a long time ago and I've never used it since :(