Pauls Dirac's equations denote the way that matter and antimatter collapse together to annhilate and give off radiation. So you end up having an electron exploding when it touches an anti-electron (positron). If the time value in Dirac's equation is positive it describes the movement of the electron, if it's negative it describes the motion of the positron.
So this means that it's possible that the positron that causes the annhilation, is actually the same electron that it annhilates with, but travelling backwards through time. This positron will then travel backwards through time until it annhilates again, switches time-direction and becomes an electron. You can imagine the timeline of the electron-positron looking like interstellar pong. Because we only see individual moments of time, we percieve there to be billions upon billions of elctrons, but it could be exactly the same electron, which would explain why they are all identical.
obviously there are some issues with this, like the unbalanced amount of anti-matter to matter ratio, and conservation of energy etc. I'm not a master physicist so I can't really answer these questions, but I heard this from Michio Kaku, so go bug him, also he deserves credit.
