There is definitely more than one electron, if only because when you create an electron-positron pair, you can then annihilate those two with each other, and that doesn’t form a loop with the others.
If the only thing keeping them the same were identity, then these virtual electrons could be different. And don’t bring up ‘borrowed’ energy or mass—going off-shell is just a dynamical feature like position or velocity.
There’s also the observed matter-antimatter asymmetry. Even if you want to argue that virtual electrons aren’t real and thus don’t count, it still seems to be the case that there are a lot more electrons than positrons. If it was just one electron going back and forth in time, we’d expect at most one extra electron.
Not to mention the fact that positrons = electrons going backwards in time only works if you ignore gravity.
There is definitely more than one electron, if only because when you create an electron-positron pair, you can then annihilate those two with each other, and that doesn’t form a loop with the others.
If the only thing keeping them the same were identity, then these virtual electrons could be different. And don’t bring up ‘borrowed’ energy or mass—going off-shell is just a dynamical feature like position or velocity.
There’s also the observed matter-antimatter asymmetry. Even if you want to argue that virtual electrons aren’t real and thus don’t count, it still seems to be the case that there are a lot more electrons than positrons. If it was just one electron going back and forth in time, we’d expect at most one extra electron.
Not to mention the fact that positrons = electrons going backwards in time only works if you ignore gravity.
“Well, maybe they are hidden in the protons or something”
;-)