Has physics neared the end of its tether? I recently saw a strange National Geographic special about scientists positing the existence of parallel universes in which things that have not happened in our universe are happening. For example, if you decide to go one way on a street, there is a universe in which you are going the other way, and this “splitting” goes on pretty much infinitely, for every action. This idea is premised on quantum behavior, the way in which subatomic particles appear to be in more than one place at the same time.
There are also replicas of us throughout the universe. The explanation for this is that there are a limited number of molecules in existence, and so only a limited number of combinations is possible. It stands to reason that we all have had to be copied quite a few times because there aren’t enough molecules to make entirely new combinations every time somebody pops into existence. I wasn’t sure, but I think that the universes in which we are going the other way on the street were different from the universes in which our replicas are living their own lives, separate from our decisions.
It was all very puzzling. The only bit of actual science seemed to be some observations of a galaxy of stars sliding out of place. Things became clearer, however, when a female physicist propounded the main idea — that we not think of our world as being unique in any way. There are probably dozens of worlds like ours all over the place in the multiverse, so our old Earth is really quite mundane and run of the mill. Physicists have known about quantum behavior and the notion of parallel universes splitting off from subatomic particles for decades, but they used to ignore it. They have lately taken it up again, conveniently in time to counter calculations of the astronomical odds against the elements of life developing as they have done here. And the other clarifying point was that in the bizarro parallel universe, the 9/11 attacks could have been carried out by Christian fundamentalists, an idea which must be very gratifying for some.
I suppose physicists could devote themselves to figuring out why, given the inexplicability and unpredictability of quantum behavior, we still have a relatively understandable world. But perhaps there are things even science does not want to know.