Cómo se pronuncia "photon:"

and even a new conceptual model of the photon.

But why do the atoms emit light just because another photon passes by? It's actually pretty

at once, until it interacts with the outside world - normally a photon

The laser pointer on the moon is basically the same - each photon travels to the moon

have no mass. The one for electromagnetism, for instance, is the photon.