…he was bored with the “will it fly” question: so here you are, a new question. Have a play with this one: may be scope for some interesting analyses.
What happens when light is reflected vertically off a mirror? Does it briefly, ever so briefly, slow to zero as it changes direction?
Nao
The human race is a species so incredibly intelligent that it has invented
Gods to explain anything it does not understand…although my friend Dave
said no amount of Gods will ever explain how a bra can be removed without
disturbing the T-shirt. I told him the process is called a Moebius strip.
The other side of the T-shirt remains unreachable.
The human race is a species so incredibly intelligent that it has invented
Gods to explain anything it does not understand…although my friend Dave
said no amount of Gods will ever explain how a bra can be removed without
disturbing the T-shirt. I told him the process is called a Moebius strip.
The other side of the T-shirt remains unreachable.
In the split split split split split second that it hits the mirror, the light would stop for just that smlal amount of time, and then reflect back at the speed of light
The way you are wording your question it sounds like you are objectifying light, as if it were some sort of matter that would be bound to Newtonian mechanics… I’m not falling into that trap!
Be it a particle or a wave, a photon can be created or destroyed, given the proper conditions. Whilst traversing a high-Z material, a photon has a decent probability of converting into an electron-positron pair. That pair also has a probability (albeit smaller) of self-annihilating, leaving a photon in it’s place. In effect, the photon would have disappeared and reappeared at a later time in a different place, and no one would know any better.
In the phenomenon known as reflection, a photon becomes absorbed by the reflecting media, exciting an atom therein. Unable to maintain its excited state, the atom relaxes and releases a photon. This released photon is not the same photon that first struck the atom. With sufficient knowledge of quantum mechanics, one can derive the Fresnel equations showing that the photon will be released at an angle equal to its incidence upon the reflecting media. Treating light as an electromagnetic wave, one can also make such a derivation using basic principles of electrodynamics.
So the short answer is no. The photon never stops, and assuming a perfect reflector, the photon never even slows down. It simply disappears and reappears a short time later with a different trajectory.
We always labelled our photons in physics class so that we knew which were which… what’s happening in education these days?
AFAIK, there really isn’t any sense of a change in speed with photons, just frequency/wavelength and direction. Is it possible to slow one down? The light that just barely escapes from a black hole at the event horizon is still travelling at c, is it not?
Also, under general relativity, I understand, there is no sense of a photon’s trajectory, since they can only travel in straight lines. Is that part of the definition of general relativity, or is that just a consequence of such?
(I’ll just stay in my happy little bubble, don’t even tell me it’s a particle. 
)
