Is There a Universe That Exists?

The problem with all those other universes that you have in the different versions of my traverses is that we can't observe them. So why do physicists believe that those other universes actually exist? Well, it's because they show up in their mathematics. It's not that there are any observations that speak against their existence either. If you want to, you can believe in those other universes with copies of you. But you shouldn't think that science actually delivers evidence for it.