> Another possibility is that they bounce backward in time, and try again.. which is silly. This sounds like the single-electron universe theory[0] But in the

> Another possibility is that they bounce backward in time, and try again.. which is silly. This sounds like the single-electron universe theory[0] But in the electron case, we experience the single electron in multiple places at once. In your case, if the photon were trying all possibilities by going forward and backward in time, wouldn't we experience the photon in all places at once? [0] https://en.m.wikipedia.org/wiki/One-electron_universe https://en.m.wikipedia.org/wiki/One-electron_universe