“We are actually living in a million parallel realities every single minute.” -Marina Abramovic
Ever since quantum mechanics first came along, we’ve recognized how tenuous our perception of reality is, and how — in many ways — what we perceive is just a very small subset of what’s going on at the quantum level in our Universe. Then, along came cosmic inflation, teaching us that our observable Universe is just a tiny, tiny fraction of the matter-and-radiation filled space out there.
The observable Universe might be 46 billion light years in all directions from our point of view, but there’s certainly more, unobservable Universe just like ours beyond that. Image credit: Wikimedia Commons users Frédéric MICHEL and Azcolvin429, annotated by E. Siegel.
There are very real possibilities of other Universes, including ones with different fundamental laws and constants, differing quantum outcomes existing in disconnected regions of space, and even the fantastic one of parallel Universes and alternate versions of you and me. It’s a fascinating possibility, but what does physics have to say about whether it reflects our reality?
A huge number of separate regions where Big Bangs occur are separated by continuously inflating space in eternal inflation. But unless there’s a truly infinite amount of space out there, the number of possible outcomes grows faster than the number of possible Universes like ours. Image credit: Karen46 of http://www.freeimages.com/profile/karen46.