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Contracting Universe?

by JPadinske
Tags: big bang, contracting, expansion, origins
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Drakkith
#19
Jun1-12, 08:40 AM
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Quote Quote by al_amana View Post
The field of physics in general is so broad now and still broadening that it's hard enough to get anywhere to begin with and then to be essentially labelled a "crackpot" for posing some questions doesn't do much for the status of PF and the stigma already attached to the boys club that is The BBT.
I cannot do anything to this "stigma" of the BBT and I wouldn't choose to do much different involving PF. In order to keep the forum running smoothly certain steps must be taken which unfortunately do sometimes lead to innocent people with the best intentions of learning being put off by being receiving a warning or infraction by an admin. All I can suggest is to understand why these things have happened and not hold it against anyone.

As for your removed thread, since it is believed that there is no edge or surface to the universe your question is entirely moot.
al_amana
#20
Jun1-12, 09:01 AM
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I will do my best to stay within the rules........

In regards my point being moot.

Could you perhaps explain this a bit better or point me in the right direction. I understand the analogy used to describe the BBT i.e. expanding universe, is a inflating balloon. Is it being suggested that there is a type of "blending" that occurs at the outer most reaches? Regardless, I think my question still stands, as there must be some kind of interface to pass through or a type of transition that occurs out there?

Thanks again for your time and comments.
Drakkith
#21
Jun1-12, 09:15 AM
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Quote Quote by al_amana View Post
Could you perhaps explain this a bit better or point me in the right direction. I understand the analogy used to describe the BBT i.e. expanding universe, is a inflating balloon. Is it being suggested that there is a type of "blending" that occurs at the outer most reaches? Regardless, I think my question still stands, as there must be some kind of interface to pass through or a type of transition that occurs out there?
The balloon analogy is simply that, an analogy. Remember that in the analogy there is no third dimension, there is only the 2 dimensions that the surface represents. Any 2d beings living on there would NOT be able to observe any third spatial dimension. So while we say the balloon is expanding, that is only applicable to our own point of view as a balloon is a 3d object, not a 2d one. From a 2d persons point of view there is no balloon, only a 2d surface that never ends but comes back around on itself. Curiously for them, over time the distance around this surface appears to be getting larger with time, and any objects that are stationary to each other appear to get further away from all other objects over time without actually moving with respect to the surface.

For our actual universe we mean that, similar to the surface of the balloon, there isn't an edge and things can get further away from each other without actually moving in the normal sense. Obviously we live in a universe with 3 spatial dimensions so the balloon analogy doesn't explain everything, it is merely an example used to help people visualize what is happening. Realize that this is a very difficult concept to grasp for some people that may take some time.

Whether our universe is actually like the surface of the balloon in that it curves back around on itself is unknown. It could be that way or it could truly be infinite in size. We currently have no way of knowing and we may never have a way of knowing.
al_amana
#22
Jun1-12, 09:22 AM
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Thanks I get it now.
Alldarknow
#23
Oct22-12, 07:29 AM
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If the Universe were in fact contracting, would not all the observed data, red shift etc, from our reference point remain unchanged. Everything would still be moving apart at given rates as our galaxy's local area contracted. Matter closer to contraction would be accelerating faster, leaving us behind and galaxy's further out would seem to be moving away faster as we accelerated away from them. This explanation "however novel" could remove the need for Dark Matter/Energy, singularity and many other cosmological questions we don't have answers for.
phinds
#24
Oct22-12, 08:19 AM
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Quote Quote by Alldarknow View Post
If the Universe were in fact contracting, would not all the observed data, red shift etc, from our reference point remain unchanged. Everything would still be moving apart at given rates as our galaxy's local area contracted. Matter closer to contraction would be accelerating faster, leaving us behind and galaxy's further out would seem to be moving away faster as we accelerated away from them. This explanation "however novel" could remove the need for Dark Matter/Energy, singularity and many other cosmological questions we don't have answers for.
I take it you have not even bothered to read the posts in this thread.
Drakkith
#25
Oct22-12, 10:21 AM
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Quote Quote by Alldarknow View Post
If the Universe were in fact contracting, would not all the observed data, red shift etc, from our reference point remain unchanged. Everything would still be moving apart at given rates as our galaxy's local area contracted. Matter closer to contraction would be accelerating faster, leaving us behind and galaxy's further out would seem to be moving away faster as we accelerated away from them. This explanation "however novel" could remove the need for Dark Matter/Energy, singularity and many other cosmological questions we don't have answers for.
There is no point that would be "closer to the contraction", similar to there being no point "closer to the expansion". The understanding expansion, is fundamental to understanding practically all of cosmology. Expansion happens everywhere at all times. It is simply an increase in the distance between all unbound objects, where the further away two objects are from each other, the faster they recede from each other. Think of points on the surface of a balloon. As you blow it up, the points that are further away from each other increase their distance faster than points that are closer to each other. You can try this at home with a balloon and a marker or pen.
Alldarknow
#26
Oct23-12, 03:10 PM
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@phinds read every word Mr rude. I don't see anything in this thread that fully addresses jpadinski's query apart from obvious chapter and verse you can read in any secondary school text book. The guy had obviously come to the wrong place for a sensible conversation regarding his musings, which are BTW hinted at by respected individuals in the scientific community... @Drakkith I do fully understand the big bang/expansion/inflation/ and explain it to others as you've mentioned with the balloon analogy. However, the observations we make, from whatever instrument we build will only allow us a view of objects long long ago, in some cases our view can be Billions of years old, a lot can happen in that time. He's thinking outside the box, all I think he's saying is unless you had an observation point beyond our Universe limits or were able to identify the exact boundaries you can make as many observations/calcs you want but unless you have a reference for correlation you MIGHT not be right.
Drakkith
#27
Oct23-12, 06:34 PM
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Quote Quote by Alldarknow View Post
@phinds read every word Mr rude. I don't see anything in this thread that fully addresses jpadinski's query apart from obvious chapter and verse you can read in any secondary school text book. The guy had obviously come to the wrong place for a sensible conversation regarding his musings, which are BTW hinted at by respected individuals in the scientific community...
This isn't the place for speculation and personal theories. This is a forum whose purpose is to teach currently accepted mainstream science. If someone is not here for that, then they should leave. It is irrelevant if some scientist somewhere THINKS they know something. If they haven't written up a formal theory and published it for peer review then we can't discuss it seriously.

@Drakkith I do fully understand the big bang/expansion/inflation/ and explain it to others as you've mentioned with the balloon analogy. However, the observations we make, from whatever instrument we build will only allow us a view of objects long long ago, in some cases our view can be Billions of years old, a lot can happen in that time.
Of course. But nothing of what you or the OP has mentioned is able to match up to our observations. A contracting universe does none of what you claimed it does.

He's thinking outside the box, all I think he's saying is unless you had an observation point beyond our Universe limits or were able to identify the exact boundaries you can make as many observations/calcs you want but unless you have a reference for correlation you MIGHT not be right.
We MIGHT not be right? Are you kidding me? We KNOW we might not be right. That is one of the mainstays of science! It's built into the scientific method! That's why you will never hear a decent scientist say that they know something is 100% true, no matter what. Thats why you have things like the announcement of the finding of a new particle that looks like the Higgs at a confidence level of 5 sigma, or about 99.99994%.

And no, no one in this thread is "thinking outside the box". The issue is that there are many ways to make you think you are outside the box and it takes years of study and education to know which ones have been previously identified as not being outside the box and to learn how to identify what is outside the box and what isn't.
mkeller
#28
Nov27-12, 04:48 PM
P: 1
Observed Cosmological Redshifts Support Contracting Accelerating Universe.
http://arxiv.org/pdf/1207.0955v1.pdf
Alldarknow
#29
Nov29-12, 07:00 AM
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@mkeller Nice post mate, still reading it through but so far very interesting.. Cheers
Garth
#30
Nov29-12, 10:05 AM
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Quote Quote by mkeller View Post
Observed Cosmological Redshifts Support Contracting Accelerating Universe.
http://arxiv.org/pdf/1207.0955v1.pdf
That paper is deliberately ignoring the nearer galactic red shifts.

Assuming that current universe started to contract and accelerate at z = 0:8 reproduces SN Ia observable data. It also leads to an older universe with age t0 = 24 Gyr. The contracting stage of the universe also allows to explain association of the high redshifted quasars and low redshifted galaxies.
If, as he says in the conclusion, the universe started contracting at z ~ 0.8 then galaxies less than z = 0.8 would show a blue shift. None do except some of the very nearest ones, such as Andromeda, M31 because of their peculiar motion.

Regards,
Garth
Reptillian1
#31
Dec5-12, 05:02 PM
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Quote Quote by Drakkith View Post
We MIGHT not be right? Are you kidding me? We KNOW we might not be right. That is one of the mainstays of science! It's built into the scientific method! That's why you will never hear a decent scientist say that they know something is 100% true, no matter what. Thats why you have things like the announcement of the finding of a new particle that looks like the Higgs at a confidence level of 5 sigma, or about 99.99994%
At least someone is being honest here. There is nothing wrong with taking consideration of other models which explains our observations, but one has to assume the standard model is correct or at least the most plausible for lots of reasons as in one of them is that it explains lots of our observations and undoubtedly shows it.
Chronos
#32
Dec5-12, 10:56 PM
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So, how does the contracting universe hypothesis explain the integrated Sachs-Wolfe effect?


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