Does Light Really Stop and Turn Back When Reflected?

[StevenJParkes]

Does the light stop and turn back or does it interact with the surface and make a u turn.

 

[zhermes]

When light is truly reflected, it does not 'stop'---the waveform is essentially redirected from the forward direction to the reverse direction. If you've played the game Portals, you might imagine the wave going into and back out of the same place.

If the light isn't actually reflected, but is instead absorbed and re-emitted in the reverse direction, then there is some very very small period of time between it being absorbed and re-emitted.

 

[StevenJParkes]

When light is truly reflected, it does not 'stop'---the waveform is essentially redirected from the forward direction to the reverse direction. If you've played the game Portals, you might imagine the wave going into and back out of the same place.

If the light isn't actually reflected, but is instead absorbed and re-emitted in the reverse direction, then there is some very very small period of time between it being absorbed and re-emitted.

I read an argument that light does not actually slow down when it goes from one medium into another but that it is absorbed and re-emitted. This is partly why I asked the question. Pretty sharp of you to see that.