physics question how fast does something produce light.

The photons don’t join together, like cars on a train. The photons don’t really interact with each other.

If you do an experiment that measures the wave behavior of your light, you’ll see wave behavior. If you do something that measures particle behavior, you’ll see photons. What it’s doing when you aren’t measuring, you really can’t say.

I’m not saying you’re wrong 'cause I don’t really know myself but wave front theory(wavelets) works on assumptionm that the leading egde of the light can always be assumed to be made of tiny points sources of wave that just happen to interfere constructively only in the dircetion of the beam and destructively all other directions, doen’t this assume the photons are interacting with eachother?