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RichardKennaway comments on [LINK] Sean Carrol's reflections on his debate with WL Craig on "God and Cosmology" - Less Wrong
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Really? I don't know fundamental physics (I take this to mean quantum mechanics and general relativity) well enough to directly say anything about it. However, as far as I know, all of the mesoscopic stuff (electromagnetism, elasticity, thermodynamics, chemical processes, etc. on the scale of everyday objects) obeys causal differential equations, by which I mean the subject matter of this book. The same is true, to the extent that I know anything of the matter, of quantum mechanical descriptions of the time evolution of a system. Some of these also have non-causal formulations (e.g. principles of least action), but there is always a causal description: one that does not require any future boundary conditions in order to calculate future trajectories.
If physicists don't explicitly talk about causes, it's because the concept is too basic and agreed-on to need talking about. They don't talk much about "truth" either. Or "arithmetic".
Classical physics, excluding thermodynamics, is invariant under time reversal. I certainly wouldn't call that causal, but maybe I'm missing something.
Also quantum physics, in no-collapse interpretations. (Except for a few processes like kaon decays, that arguably are time invariant "in spirit" because they are CPT invariant).
A couple of points:
Sort of true, although to make a "causal description" of GR one has to do unspeakable violence to the Einstein equation, which simply states that curvature = energy-momentum density. It also excludes many of the popular solutions with closed timelike curves and other anomalies. In any case, if you don't need a causal formulation, or if you can derive it from a non-causal one, then asserting that causality is essential in physics would be reaching.
That's not true. Physicists do explicitly talk about causality, as in, how much of the future can be influenced by the past. Scott Aaronson recently wrote a paper about it.
All that said, however, I believe that what SC and especially WLC meant by causes in their debate was "external causes", more in a sense of a creator, or at least fire in the equations, not the mundane idea of equations of physics being castable in a hyperbolic form. And that vague notion of external causes is what SC objected too.
You are quoting out of context. The issue is the cause of the big bang and the cause of the particular values of fundamental constants. That physical laws say that the past causes the future is relevant to neither of these points.
(Shminux said the same thing, but buried it by pursuing your tangent.)