Implications of Time-reversal asymmetric quantum physics

Schneibster
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So what is the implication of time-reversal asymmetry in relativistic physics, now that we know that quantum mechanics is not time-reversal symmetric to 14 standard deviations?
 
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Schneibster said:
So what is the implication of time-reversal asymmetry in relativistic physics, now that we know that quantum mechanics is not time-reversal symmetric to 14 standard deviations?

GR is known to be in conflict with several aspects of quantum mechanics. Some successor theory (to one or both) is needed. The majority view is that GR is classical, successful, approximate theory with the same relation to some successor as Maxwell's equations are to QED.
 
PAllen said:
GR is known to be in conflict with several aspects of quantum mechanics.
This one makes two I know of, one old one added to one I just found out about; the old one is the infinite probabilities when attempting to accomplish the first quantization of gravity. Are there yet others?

This is actually pretty definitive, I've had some conversations back when it wasn't clear that CP violation necessarily proved T reversal asymmetry, with some folks who thought I was nutty for saying it did and that it accounted for baryon asymmetry. I'm now hearing that once all the CKM and PMNS matrix mixing angles are figured out, we expect to see that it exactly accounts for the matter-antimatter asymmetry, and that the statistics have bent toward this determination as more BaBar results have come in- correct me if I'm wrong.

PAllen said:
Some successor theory (to one or both) is needed. The majority view is that GR is classical, successful, approximate theory with the same relation to some successor as Maxwell's equations are to QED.
That makes sense. Still, it's not any of the obvious low-order quantum theories.
 
General Relativity does not know about the details of particle physics, its only contact with matter is via the stress energy tensor. If particle physics is not time reversal invariant, does that have something to say about Tμν? Does Tμν have to be complex or something?
 
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From $$0 = \delta(g^{\alpha\mu}g_{\mu\nu}) = g^{\alpha\mu} \delta g_{\mu\nu} + g_{\mu\nu} \delta g^{\alpha\mu}$$ we have $$g^{\alpha\mu} \delta g_{\mu\nu} = -g_{\mu\nu} \delta g^{\alpha\mu} \,\, . $$ Multiply both sides by ##g_{\alpha\beta}## to get $$\delta g_{\beta\nu} = -g_{\alpha\beta} g_{\mu\nu} \delta g^{\alpha\mu} \qquad(*)$$ (This is Dirac's eq. (26.9) in "GTR".) On the other hand, the variation ##\delta g^{\alpha\mu} = \bar{g}^{\alpha\mu} - g^{\alpha\mu}## should be a tensor...
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