I’ve been reading, or really listening to “The Hidden Reality” by Brian Greene. Greene is one of the scientists who can make advanced science accessible to the general public. There are too few of them left since the passing of Carl Sagan and Stephen J Gould. Anyway, The Hidden Reality is all about the concept of parallel universes or the multiverse. Greene describes all the various kinds of universes that might exist.
It is an interesting book and an intriguing subject. I’m skeptical about the multiverse concept though. The problem is that there is no evidence that any of the various multiverses actually exist. And, given that each universe in a multiverse is self-contained with no means of communicating with one another, it is not likely that we will ever have such evidence. As I said, it is an interesting concept, but unless they can come up with a testable hypothesis about the matter, I don’t think that it can be, strictly speaking, science. You might as well argue about how many angels can dance on the head of a pin.
By the way, the number of angels that can dance on the head of a pin is infinite. Angels are not composed of matter/energy and do not take up physical space, you see.