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Ether and Big Bang.

  1. Jan 23, 2009 #1
    Does anyone know if this ether which light traveled through existed before the Big Bang?
     
  2. jcsd
  3. Jan 23, 2009 #2
    There is too much awkwardness between cosmology and quantum mechanics and what space is right now to expect any kind of agreement.

    Cosmologists tend to view the big bang as an explosion of space so to speak. At least in the sense that space was once denser, and the universe much smaller, but suddenly it began to expand. There are still two ways you could go with this though. The first would be that the universe was just a single dense point, and the forces we know of now, were not yet around. Another take could be that big bang just means that the universe has been expanding, and that it was never a single point or anything, it was just smaller.

    An awkward fact is that scientists have recently discovered that there is an ether. Many cosmologists had thought that space was nothing. Now that we know better, cosmology might begin to change as Quantum Mechanics gets more integrated. I think that we may have to have two terms, a physical and mathematical, ether, and space. One not being the same as the other, and not meaning the same thing. So, when you say space, you are just talking about the metric, and when you say ether, you are talking about something real.
     
  4. Jan 23, 2009 #3
    Newton proposed that there was a medium or ether in space that light traveled through. This was disproved. Space time is perhaps permeated with dark energy which in one explanation is referred to as quintessence. Redhedkangaroo, it is scientifically awkward to talk about anything “before the big bang” since that is the beginning of everything that can be addressed in any way that can be disproved. Jreelawg, do you have a link to this recently discovered ether?
     
  5. Jan 23, 2009 #4

    marcus

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    Arch, you may be promoting a popular misconception here. I don't know of any professional who has made this kind of pronouncement recently, so I wonder if you could find a fresh link to back up your claim---since 2005, say---and not to some popularized account but to something in the research literature.

    The popular mistake is to imagine there's some reason in principle why models which extend back before the bigbang time mark can not be empirically falsifiable.
     
  6. Jan 23, 2009 #5
    Thanks, I only implied that such a discussion is awkward. I am a proponent of such discussion, but some of the other forums I frequent aren't, so I presented a cautionary statement.
     
  7. Jan 23, 2009 #6
    So can anyone answer the question or.....
     
  8. Jan 23, 2009 #7
  9. Jan 23, 2009 #8

    marcus

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    It would help if you provided a link to what you mean by "this ether". There is a modern aether model due to Jacobson and Mattingly, called Einstein aether (EA)

    Here is a current status report on EA
    http://arxiv.org/abs/0711.3822
    Einstein-aether gravity: theory and observational constraints
    Ted Jacobson
    8 pages, for proceedings of 4th Meeting on CPT and Lorentz Symmetry
    (Submitted on 24 Nov 2007)
    "Einstein-aether theory is general relativity coupled to a dynamical unit timelike vector field. A brief review of current theoretical understanding and observational constraints on the four coupling parameters of the theory is given."

    There are many other papers about the new aether theory of gravity, here is a keyword search, ranked by citation count, using the keyword "aether". Most of the articles are after 2004.
    http://www.slac.stanford.edu/spires...IND+K+AETHER&FORMAT=www&SEQUENCE=citecount(d)

    Wikipedia seems to have no clue in this case.

    =================

    Redhed,
    let's see if we can rephrase your question to be more meaningful.
    Right now it's trivial. Scientific theories are never verified, they eventually get falsified and replaced by better theories, typically. Science for the most part is not about sure knowledge. In particular cosmology and fundamental particle physics are mathematical science, which means constructing mathematical models that fit data more or less well and are useful for prediction. And then improving the model as needed. The question to ask about a model is not "is it true?" but "does it fit?" (and there are other considerations like simplicity, consistency, elegance, generality...)
    So if you are talking about absolute certain knowledge, the obvious answer is nobody.

    What we can say about conditions leading up to the big bang, and what the big bang consisted of, depend on the model. There are several models and currently an important job is deriving predictions that can be tested by making observations.

    There is an important class of models where conditions prior to bang are essentially similar to conditions after, except you have contraction instead of expansion. If you do a ranked keyword search for quantum cosmology in the professional literature this type of research dominates the field. It's untested as yet, but it's what is attracting the most research attention.
    http://www.slac.stanford.edu/spires...+DATE+>+2005&FORMAT=www&SEQUENCE=citecount(d)
    Nearly all of the top twenty papers here are bounce cosmology (no singularity.)

    So the critical question to ask is how seriously we should take Jacobson-Mattingly's modified version of general relativity---the "modern Aether" or "new Aether" theory. They call it Einstein Aether Gravity. It is just a modified version of geometry that has this additional hard-to-detect field.
    Jacobson is very concerned with empirical testing of everybody's theories, including this one. He is a worldclass phenomenologist (one specialized in testing) as well as theorist. I doubt he believes in EA gravity. Belief is not the name of the game. The aim is to get consistent interesting models out on the table, that fit all the past observational data, and that can be tested by future observation---by machines that are scheduled to be launched into orbit such as the Planck observatory, or are in planning.
     
    Last edited: Jan 23, 2009
  10. Jan 23, 2009 #9
    Marcus,
    What is a point of that article?
    I read it, at it looks like "We have a theory of aether, but in order to match current observations (and GR) it must be fine-tuned so the difference between it and GR should not exceed 0.001" :)
     
  11. Jan 25, 2009 #10

    jtbell

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    Posts discussing the existence/nonexistence of the luminiferous ether have been moved to a separate thread in the Special & General Relativity forum.
     
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