In other words, even though a single collision is time-symmetric, the development of the whole simulation is asymmetric, because the distribution of small balls at any moment is correlated with where the large balls have been but uncorrelated with where they are going next.
It would be fascinating to observe an instance of this universe that was symmetric. It is certainly possible. With the right starting conditions you could have a universe that runs forward but looks like it is being played backward. With another set of starting conditions a universe could be found that looks just as plausible running forward as backwards.
It would be fascinating to observe an instance of this universe that was symmetric. It is certainly possible. With the right starting conditions you could have a universe that runs forward but looks like it is being played backward.
It would be fascinating to observe an instance of this universe that was symmetric. It is certainly possible. With the right starting conditions you could have a universe that runs forward but looks like it is being played backward. With another set of starting conditions a universe could be found that looks just as plausible running forward as backwards.
I describe such an instance here.