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The art to become special and a bounce

  1. Feb 5, 2008 #1
    The art to become special and the bounce.

    Roger Penrose in his book “The Road to Reality” showed us a road/trajectory from a super special low entropy state, at the Big bang, to nowadays’ less special and higher entropy state. Nothing wrong with symmetric physical laws valid during that trajectory, but a reverse road is so improbable that in practice it is impossible that it will ever occur. Entropy, practically, increases continuously according to our second law of thermodynamics.
    I have a few remarks and questions here.
    1) To start with: to me, in spite of that, it seems not real that the universe will die as a consequence of the second law.
    Further:
    2) Coincidentally it seems to me that the shown Penrose trajectory (page 730) starts after a bounce provided that the LQC bounce (Ashtekar, Bojowald) took place.
    3) As a consequence Penrose story/(shown trajectory) appears to me only the after bounce (WH) state story and does not take into consideration (,or tell) a pre bounce (BH) story of the pit of our verse. Or does it?
    4) So far we were never able to look into any BH because of its Schwarzschild shield.
    5) But, of course we are (with our observable universe) in our own pit of our verse, presumably, after the inner bounce i.e. in its WH phase happened. It is now and here where we notice the 2nd law.
    6) But might it be possible, or does or can bounce theory say anything about a possibility, that during the pre bounce state in a BH (the, or) a decrease of entropy takes place, eventually with a higher probability (than in a WH state) because of the shrinking domain (increasing pit’s density), which of course we could never observe (so far)?
    7) To me an explanation for a recovery to a low entropy state, relying on state dependent (BH<-> WH) statistics, might seem of (great) importance to, easier, explain infinity in time, back and forward.
    It might be here where Poincaré’s recurrence principle can be realized in full?
    [8) It might then eventually be not the case that a full recovery takes place in just one bounce, but averaged over all bounces/verses of the universe’s space time the second law might finally be eliminated?]
     

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  3. Feb 5, 2008 #2

    marcus

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    Ooops!
    I was just reading and responding to your other thread, and what you said reminded me of Penrose ideas. So I was recommending a Penrose lecture to you.

    And here I find you are already ahead of me! You have already been thinking about his proposal.

    So my post on the other thread was not necessary. I was talking about this lecture:
    www.newton.cam.ac.uk/webseminars/pg+ws/2005/gmr/gmrw04/1107/penrose/

    OK, so I will look at what he says on page 730 of his book and get back to you later this evening.
    ======================

    BTW my suspicion is that the second law requires an observer, who determines what shall be the macrostates.
    So although I respect Penrose and follow what he says with much interest, I do not fully accept his conclusions about the cosmological bounce. I don't think one can so easily conclude that a bounce would violate the second law. (who is the observer?)

    I have to help my wife fix supper, but later this evening I will think about it some more. thanks for raising some interesting issues!
     
    Last edited: Feb 5, 2008
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