the size of the multiverse
I’ve been thinking recently about the size of the multiverse, and how we experience the multiverse in movies. It’s showing up a lot at present, particularly in the Marvel Cinematic Universe, as well as older shows such as Sliders.
The reason, or a reason, why I’ve been having these thoughts is that I think the multiverse has to be much more complicated than what we’re seeing in its representations. And this comes from some nineteenth century mathematics due to Georg Cantor.
My understanding of the standard interpretation of the multiverse is that at each moment, reality branches to take into account all possibilities. One issue with this description is that at each moment, there are infinitely many possibilities, and so the structure is remarkably difficult to imagine.
There is a way of approaching this structure, but there is a piece of information we need first. Namely, if we have an infinite branching of possibilities at each moment, then one question we have to ask is, which infinity.
And this is the piece of nineteenth century mathematics. Infinity is not a unitary concept: there are multiple sizes of infinity. Strange, yes? But more than this, we mathematicians have a machine for comparing infinities, and a machine for generating a larger infinity from any given infinity, and other questions such as whether there are infinities between the ones we can construct using our machine.
But in movies and in television, the multiverse is often portrayed as a discrete object, the different universes separated from one another and labelled. And I’m happy to agree that this might be easier.
But one of the thoughts I can’t shake, one of many, is how it might be possible to describe the multiverse in a way that takes all of this on board, for an audience that may not have had exposure to this reality of multiple different infinities.
Challenges, oh all the challenges. Perhaps this story has already been written and I just haven’t come across it, and if this is the case, please do let me know.
multijimbo 