Earth? Some people think there are multiple universes; different realities. Sophia Chen on the book Many Worlds:
Many Worlds says, why don’t we just treat you, the observer, as your own quantum mechanical system? You’re made of quantum mechanical particles also. So what happens when you, the observer, looks for the electron? The electron starts in a superposition of many possible locations. When you look, you evolve into a combined system of you and the electron in a superposition. The superposition consists of the electron being here and you seeing it here, plus the electron being there and you seeing it there, and so on.
Uh, OK. So that means multiple universes all close together? Wait. It gets worse.
We know our observable universe looks the same, on average, many billions of light-years away from here. There’s a cutoff to how far we can see, so it could be infinitely big. If the universe is infinitely big, and it looks the same everywhere, that guarantees that infinite copies of something exactly like you exist out there.
There must be a world out there where Apple rules and prices are lower.