It's About Time, Entropy, and Other Universes

"Does Time Run Backward in Other Universes?"
Scientific American (May 2008)

"One of the most basic facts of life is that the future looks different from the past. But on a grand cosmological scale, they may look the same

"The basic laws of physics work equally well forward or backward in time, yet we perceive time to move in one direction only—toward the future. Why?

"To account for it, we have to delve into the prehistory of the universe, to a time before the big bang. Our universe may be part of a much larger multiverse, which as a whole is time-symmetric. Time may run backward in other universes...."

This article is a pretty good discussion of the current state of knowledge and speculation about how the universe works. Or, rather, how one aspect of it works: time and entropy.

It's also moderately heavy reading: I wouldn't recommend trying to finish it during a coffee break.