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Closed, collapsing universe+only photons at first -> matter when hot?

  1. Mar 10, 2014 #1
    Closed, collapsing universe+only photons at first --> matter when hot?

    Suppose we had closed, collapsing universe with a uniform thermal distribution of low energy photons like that of the CMB and no other matter (I suppose we must pick the initial conditions right for collapse to occur) . As time goes by the temperature of the radiation increases?

    By varying initial conditions can we vary the time T for collapse?

    I assume things heat up, when the average energy per photon is greater then any mass in the standard model can we expect some fraction of energy initially in the photons will now be divided among all the fields of the standard model (with some possible asymmetry between matter and antimatter via the Standard Model)?

    At energies well above any mass of the standard model can one argue that all the fields should share energy roughly equally? Would we have enough time for energy to become completely divided between all the fields of the standard model?

    Finally, does this collapsing universe in some last moments undergo the inverse of inflation?

    Thanks for any help!
  2. jcsd
  3. Mar 11, 2014 #2


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    You did not even specify a starting time to measure some T, so... yes.


    I guess that depends on the way you count fields, and on the timescale of the collapse.

    Without a clear, single theory of inflation, how could we tell?
  4. Mar 12, 2014 #3
    One thing I would add. According to high energy particle physics. As a particle reaches the same energy level as an other particle the two become indistinquishable from one another. This forms the basis of GUT. For example at high enough temperatutes you can no longer tell a neutrino form a photon or electron. By any means or other properties that particles have such as spin and momentum. Essentially they all become photons. As this includes bosons the forces also become indistinquishable. Leaving the electro-weak force ( strong, weak and electromagnetic forces united) and gravity. Their has been no sucesses in uniting gravity to the electroweak force.

    I recommend buying a copy of Griffiths high energy particle physics textbook to better understand the the above. He covers the topic in an easy to inderstand manner
  5. Mar 12, 2014 #4
    Thanks to you both! Interesting.
  6. Mar 12, 2014 #5
    Lol working from my phone so there is several spelling errors in my previous post.

    If you plan on trying to google early universe articles that describe GUT. You will find numerous misleading articles. Seldom will any two articles agree with each other. Hence my recommendation in buying Griffiths textbook. Some of the articles do have a semi decent graphical representation of GUT. However the times that the various particles and forces freeze out (becomes distinquishable) will vary depending on what the author feels is correct. Ie supersymmetry vs symmetry for example. Most of the particles predicted by supersymmetry have yet to be found. The only exception that I am aware of is the Higgs boson. However the exact number of Goldstone bosons is still in question. As far as I know there is a possible 12 goldstones. However I've yet to read any two articles on the higgs that agree on the number.
  7. Mar 14, 2014 #6


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    Please give a source for that claim.
    And charge, lepton numbers, and various other quantum numbers.

    Actually, all.
    A single Higgs boson (=what the LHC found so far) has nothing to do with supersymmetry, and supersymmetry leads to more Higgs particles (usually 5, that's the number I see all the time) - no additional particles have been found so far.
  8. Mar 17, 2014 #7
    I can't locate that line for a reference though I have seen similar statements in older early universe thermodynamics articles.

    Most likely its a poorly worded descriptive of the thermodynamic equilibrium state.

    This article probably describes the eqilibrium state better


    if I can locate the other descriptive I will happily post it. Pretty sure it was in one of my various textbooks. However they are all cutrently packed as I am in the middle of moving. New job lol so working from my phone atm
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