I remember a rather excellent story in the British science fiction comic 2000AD some time in the late 80s that addressed the issue of parallel universes. It began, “In an infinite universe, everything is possible, therefore everything exists. These are Globs…” The Globs had discovered how to glook down interdimenional glook tubes, which sucked the intelligence out of human beings. I always think of that story when parallel universes are discussed. Why shouldn’t Globs exist?
I also seem to remember that mathematics proves that there are different sizes of infinity. Perhaps Derb can demonstrate that one for us. Or, more importantly, tell us how that can mean anything.