The laws of physics as currently understood -- i.e., the laws in the best model we' ve got -- are in fact CPT-symmetric but not T-symmetric. (Because the best model we've got is a quantum field theory of the sort that the CPT theorem applies to; and because CP symmetry is violated (1) by that model and (2) in reality, according to the available evidence.)
You understand that the claim is that that is just a historical accident about the way the model was built? The idea that C and P reverse automatically if T is reversed does not make any new predictions that the old model did not. The idea that CPT symmetry is favoured by some kind of experimental evidence seems completely wrong to me. Since the two models are totally equivalent experimentally, this is an issue for Occam.
You understand that the claim is that that is just a historical accident about the way the model was built?
There is a mathematical theorem that says that no model of the same kind can fail to have CPT symmetry. There are robust experimental results that say that the real world doesn't have CP symmetry. Therefore, it is not an accident that given the general kind of model it is it has CPT symmetry but not T symmetry.
If you are claiming that it's a historical accident that we have a QFT model and not a CA-type model, then show your evidence. Specifically,...
http://lifeboat.com/blog/2011/06/dear-dr-hawking
Hey guys, my quantum physics is not powerful enough to understand this guy... Can anyone help me out with this one?
Thanks LW