If a photon does not experience time and exists in its full trajectory at a given instant, how does it “perceive” a body moving to cut its path?

Question

OK maybe ELI12 would do.

In: Physics

Answer 1

It doesn’t perceive it. It just interacts with a body somewhere on its path. From the POV of the photon, no time has passed or will ever pass. But that doesn’t mean that every photon everywhere exists forever; from the POV of the body in its path; there was no photon at one moment, then there was a photon hitting it and being absorbed. The photon experienced no time, but the electron cloud of the body that absorbed it did.