Originally Posted by **wavesearcher** From the perspective of a photon, are all photons on top of each other in the same place? |

What do you mean "on top of each other"?

Now, particles traveling at the speed of light are a little tricky to talk about but I'll give you a quick rundown.

As an object goes faster and faster it "sees" the distance along its direction get smaller. This is the Fitzgerald contraction. As a result the faster the object goes the shorter the trip. (In the object's reference frame, of course.) We can take the limit of this idea as apply it to photons.... It takes a photon no time at all to get from one place to another. (wrt the reference frame on the photon.)

As far as a "pile up" is concerned the photons may not age at all between particles to interact with but there is nothing to say that they all arrive at the same time.

That's the best guess I can make. Does that answer your question or is it something else you were asking about?

-Dan