On 7/28/2013 5:40 PM, Warren D Smith wrote:
Asimov: I don't really believe in the 2nd Law of Thermodynamics anyway for large or high-entropy initial conditions. (E.g., although the universe near us is expanding, galaxies and stars are being formed at the same time.) -------------------------------------------------------------------------
So let me bring up a related subject, as long as we're discussing physics. There are two striking aspects of the universe that are so difficult to address that physics can't touch them (so far): a) the flow of time, and b) conscious awareness. These two things must be very closely related. But very mysterious. --jeez.. A.S.Eddington once stated (1927),
QUOTE If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations—then so much the worse for Maxwell's equations. If it is found to be contradicted by observation—well these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation. END QUOTE
and, quite so. The 2nd law is true. It actually is a theorem of mathematics in Von Neumann's formulation of quantum mech with his defn of "entropy" (entropy increases during "measurements", stays same rest of time).
Being "a theorem of mathematics" just means it follows from some assumed axioms. Von Neumann's formulation is like decoherence theory without mentioning the environment. So it has the same weakness plus one more.
Now if the universe were to turn round and start contracting, I assure you entropy would continue to not decrease (and to increase).
If you just did a CPT transformation on the state of the universe you'd have universe that was obeying all the same laws of physics, except it was contracting - and hence the entropy would be decreasing. Of course no one living in this universe would notice this because the physical arrow of time would still point in the direction of expansion. So yes entropy increasing (on average) is a kind of tautology.
If the universe started out high entropy, it would not matter either. This is a statement about enormous probabilistic "forces." It holds regardless of the shrinking or expanding of the universe which is an irrelevancy. This whole ludicrous myth was started by S.Hawking in his popular book "history of time" and even though Hawking later publicly stated that him saying this was the greatest and most humiliating error he ever made in his life, this absurd myth then attained a life of its own.
Now in my paper I cited I pointed out that general relativity DOES say something about the direction of time (unlike every other physical theory in the standard model if "measurement" is regarded as not existing). Namely, there are theorems in GR like black holes can merge but not bifurcate. But can white holes bifurcate? I think so; it is only statistically improbable because of the retarded radiation boundary condition.
Efficient gravity wave emitters can exist but not absorbers. Small perturbations of the Schwarzschild metric die out with time, not grow.
That's because they radiate away energy. Brent
Previous authors have claimed GR also says nothing about time direction... the resolution of that paradox is subtle and discussed in my paper.
I therefore claimed that since this is the ONLY place in accepted physics that says something about time direction, the arrow of time (and hence measurement, entropy, etc etc) must derive from it.
There are a lot of philoso-physicists who seem to think via religious/hope
"reasoning" that the arrows of time, phenomena of quantum "measurement," etc, somehow arise from nongravitational physics. They have nothing solid and never will.
They need to come round to my picture.
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