Every time you put milk into your coffee and watch it mix and realize that you can’t unmix that milk from your coffee, you are learning something profound about the Big Bang, about conditions in the very, very early universe. This is just a giant clue that the real universe has given to us to how the fundamental laws of physics work.
Sorry to say this, but the standard of physics at Caltech has gone down greatly. When you learn that you can't unmix milk from your coffee you simply learn that physical systems that occupy a very, very, very large volume of phase space require a lot of work to be reduced to a very, very, very, small volume of phase space. The increase of entropy would be true even if God created the universe as described in the book of Genesis. It would be true even if we were heading to the Big Crunch. Now if you contemplate why your milk and coffee and you yourself exist, then you are learning something about the initial conditions of the universe. You realize that you and the milk and the coffee could have arisen only from a preceding state with lower entropy, and thus, at the Big Bang, the Universe must have been in a relatively low entropy state. Now that is something profound. But that is not what Sean Carroll writes.
