Entropy, Kalam, and First Cause

[Alex K]

Alright.
If you trace a chain of causes and effects back far enough... well, you can't do so infinitely. Because of entropy over time, there had to have been some point at which the universe was in its "most orderly" state, and the entropy has increased from there. Wouldn't it make sense to conclude that an outside force (call it "god" if you feel like, though it isn't necessarily "god", according to any traditional understanding of that word) intervened to start the chain of cause and effect, to create the orderly universe and set it into motion?

I don't see how you would conclude that. If it randomly shifts into a more orderly state by accident in some pocket of space, that's entirely sufficient. See "eternal inflation".

One more thing: let's say you posit god as an agent which sets the entropy to a small value, and to find the most parsimonious explanation, strip it of all properties that aren't needed for that, personal God properties and all that are out of the window - what you are left with is a simple statement of the fact that the universe had once a low entropy state. There's no explanatory power there, and no handle to conclude anything about the properties of this God that would justify the name.

I'm fully aware that my personal understanding of physics is inadequate for this discussion. The explanation seems to be that physics were entirely different prior to the Big Bang, and the second law of thermodynamics didn't apply then? (at least not in the same way it does now?)

That's right, we don't know what's going on prior to the earliest moments we can capture with our current theories. In general, you have to be very careful when space expands or contracts, to take this into account in the entropy calculation. This changes things radically. If you are in a state where there is no smooth spacetime at all because of quantum gravity, then all bets are off.

In eternal inflation, everything expands, but a quantum fluctuation is enough to kick a basically empty pocket of space out of inflation. It then gets heated up and expands, and that's how you get a low entropy boundary condition. Roughly (I'm just a particle physicist, not a cosmologist!)