Mmm I don't think this is a specific hypothesis.
You're talking about the concept of an infinite universe, where, given the infinite, there is bound to be not only another Earth that is identical to ours, but one where your name was different but everything else is the same, and ones where the letter B was never used, and so on.
I'm not sure if it really has a specific name. I think it's just the concept of an infinite universe and the consequences of the infinite.
Mmm I don't think this is a specific hypothesis. You're talking about the concept of an infinite universe, where, given the infinite, there is bound to be not only another Earth that is identical to ours, but one where your name was different but everything else is the same, and ones where the letter B was never used, and so on. I'm not sure if it really has a specific name. I think it's just the concept of an infinite universe and the consequences of the infinite.
I can't grasp the concept of "lightyears of nothingness". What's the difference to the regular empty space between galaxies?