Does a Light Pulse Undergo Phase Shift in a Denser Medium?

[oreo]

When a pulse of light enters a denser medium(slow medium) then is there phase shift or rather it passes unshifted?

 

[phinds]

When a pulse of light enters a denser medium(slow medium) then is there phase shift or rather it passes unshifted?

Interesting question. I can't give an answer other than my opinion which is that it does not ... it just slows down a bit. To me, it seems as though a phase shift as it enters the medium would imply a discontinuity and I can't see that happening.

 

[Doc Al]

When a pulse of light enters a denser medium(slow medium) then is there phase shift or rather it passes unshifted?

There is no phase shift of the transmitted pulse. (There will be a phase shift of the reflected pulse.)