the infinite universe + probability = infinite versions of YOU in THIS reality
found source from the theory of max tegmark “parallel universes” (its a very readable paper with multiple levels of multiverse theory explained)
first of all, you have to remember that that the observable universe is not the whole universe.
what we call the “observable universe” is just the part of space we can see, about billions light years across. it’s limited by how far light has had time to travel since the big bang, billions years ago.
but beyond that, we don’t know where the universe ends, if it ends at all. many cosmologists believe the universe is spatially infinite, meaning it goes on forever in all directions.
therefore in a finite space matter can only arrange itself in so many ways.
atoms can only combine in a finite number of ways, especially if we’re talking about a finite region of space (example the size of earth or your body or even our galaxy). the number is mind blowing huge, but it’s still finite.
therefore there are:
- finite types of particles
- finite number of wayz to arrange them
- infinite space to “work with”
SO infinite space means those combinations will repeat, eventually.
if the universe is infinite and mostly homogeneous (same laws of physics everywhere) then every possible configuration of particles should eventually repeat, just due to the sheer scale of randomness playing out over infinite distances.
this is based on something called the poincare recurrence theorem and the infinite monkey theorem, which in simple terms if you give random processes infinite time or space, eventually even extremely unlikely outcomes will happen.
as in like if you roll a dice an infinite number of times, you will get the same sequence of rolls again eventually, not once but infinitely many times.
so in an infinite universe, there could be:
- another version of you reading this message
- a version of earth where you chose a different path
- entire regions of space that are nearly identical to ours and others that are radically different
this idea is what max tegmark calls level 1 multiverse, with the idea that parallel versions of reality exist not in other dimensions but just very very far away in regular old 3D space.
