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Could the objects in the universe be shrinking?

  1. Oct 11, 2013 #1
    A very hypothetical situation:

    Might an observer outside the universe see the universe itself staying a constant size, with each of the objects within at (on average) a static centre of physical co-ordinates, yet the objects themselves are shrinking?

    Having had a single cosmology so far where my professer stated that the universe didn't necessarily start as an infinitesimally small point, but instead that everything was more dense, this occured to me as a possibility.

    Is there anything out there (doppler shift etc.) that should not occur under this model, or am I simply the next big thing in cosmology?
     
  2. jcsd
  3. Oct 11, 2013 #2

    bapowell

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    Redshift?
     
  4. Oct 11, 2013 #3
    I don't know... couldn't red shift still occur for shrinking objects?
     
  5. Oct 11, 2013 #4

    jedishrfu

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    I think its any arbitrary choice to say everything is shrinking vs the universe is expanding. I had asked some fellow physicists here at work the same question a few years ago and got no definitive answer.

    However thinking about it now, if everything is shrinking then the problem becomes one of some kind of entanglement where everything is shrinking at the same rate which seems to be against GR and QM both.

    You could see if the GR equations can be interpreted that way.

    Its an interesting idea but it is also speculative physics and this forum tends to limit discussion on the topic.
     
  6. Oct 11, 2013 #5

    bapowell

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    How does one explain the presence of a CMB without expansion?
     
  7. Oct 11, 2013 #6
    thanks
     
  8. Oct 11, 2013 #7

    jedishrfu

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    I think you should still pursue your idea comparing and contrasting it against current theory until you get a convincing answer. The journey toward the answer is reward enough unless you get a Nobel too. Sometimes these journeys lead to even more topics of research.
     
  9. Oct 11, 2013 #8

    phinds

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    THis question in one form or another is asked here a couple of times a year. The evidence against it is overwhelming. It just doesn't work.

    If your prof really said "the universe didn't necessarily start as an infinitesimally small point" then you should worry about believing what he says. The fact that the universe did NOT start as a point is so firmly accepted in modern cosmology that it is incorporated in one of the two primal concepts of the "Cosmological Principle", namely that of isotropy, which is an empirically verified description of our universe and could not be so if everything had started at one point. Are you sure you understood him correctly?
     
  10. Oct 11, 2013 #9
    Yes I will pursue the idea, even if phinds above says it is overwhelmingly wrong, when I know enough, but for now I don't know anything about quantum entanglement and I really only know the basics of relativity, I know nothing of it w.r.t cosmology. Just a basic question for a basic answer! Thanks again.

    Yes, I'm sure she probably explained it properly just that I have not had it hammered into my brain enough yet to remove the necessarily from my sentence.
     
  11. Oct 11, 2013 #10
    Could you briefly write down some of the reasons why it doesn't work that I can look into it in more detail?
     
  12. Oct 11, 2013 #11

    Chronos

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    The shrinking universe idea has been around since at least 1937. The most recent foray into it, AFAIK, is by Wetterich, http://arxiv.org/abs/1303.6878. It works just fine so long as all the fundamental forces, constants, masses, etc., scale accordingly. The bigger issue is does this tell us anything we do not otherwise already know? Does it make novel predictions not made by the standard model? Does it solve any fundamental issues without creating new ones of its own? I would say the answer is NO. It's just reinventing the wheel.
     
  13. Oct 11, 2013 #12
    Yeah that's what I figured, it just makes a bit more sense to me than the idea of space expanding into nothingness. Questions, answers, more questions.
     
  14. Oct 11, 2013 #13

    phinds

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    I just realized that no one had commented on this statement. There IS no "outside" to the universe. There is no center, no edge, and no outside.

    I recommend the link in my signature for further discussion
     
  15. Oct 11, 2013 #14

    jedishrfu

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    I think the outside the universe notion comes from the multiverse / bubble universe drawings often shown in popular magazines attempting to explain cosmology to the casual reader.

    http://journalofcosmology.com/images/MultiverseBubbleUniverses1.jpg
     
  16. Oct 11, 2013 #15

    Chronos

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    If you look at it from a spatial respect, finding a place outside the universe is quite a challenge. The universe becomes increasingly younger as you observe at increasing distance. Taken to its logical conclusion, outside the universe means pre-big bang.
     
  17. Oct 12, 2013 #16
    You may have missed the first part of my question "A very hypothetical situation". Of course I know there is no outside to the universe, you can see this when I say "it just makes a bit more sense to me than the idea of space expanding into nothingness".

    You seem to be spending more time picking apart the small fallacies of my question than actually supplying an answers to the real question at hand. It's not very helpful.
     
  18. Oct 12, 2013 #17

    bapowell

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    Yeah, and he's just told you that your hypothesis is wrong. Seems helpful to me.
     
  19. Oct 12, 2013 #18
    Where everybody else has given me reasons, he has given none. No major scientific discoveries were ever made by somebody saying 'No, it is just wrong', a budding physicist learns nothing that way.
     
  20. Oct 12, 2013 #19

    jedishrfu

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    Before the commentary dissolved into chaos I suggest the thread now be closed.

    While its true naysayers will seldom provide proof, you must learn how to deal with that form of discouragement and move on to find the answers yourself.

    With cosmology in particular, we arre working with the very fringes of our scientific theory and in a few years the things we believe true now with new data and theories could have a completely different interpretation.

    The academic world has many unique individuals and is very harsh in its criticism of new ideas but that's what makes you stronger, helps you find the flaws in your theory and brings forth the very best ideas. Academic evolution of the fittest. It can't be any other way so just persevere and learn from your failures.
     
    Last edited: Oct 12, 2013
  21. Oct 12, 2013 #20

    bapowell

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    Did you read phinds' link? Nobody is saying "No, it is just wrong". If you spend the time to understand why there is no outside to the universe, say, by reading phinds' link, you might not feel so slighted. Part of being a "budding physicist" is to be humble and to learn as much as you can. People on this forum are simply trying to help you learn. There are good reasons for not supposing that there is an outside to the universe -- these reasons are grounded in our understanding of gravity in terms of differential manifolds. If you'd like to understand this more, please ask.
     
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