What i meant by ' the mirror reflect light?

Answer 1

it means that the light reflecs

Reflection is surprisingly poorly understood in quantum terms. This is demonstrated by the fact that a mirror moving in a vacuum reflects light back to a source at the speed c with respect to the 'rest frame' of the ('non existant') vacuum, not with respect to the moving mirror.

This indicates some of our current fundamental assumptions are wrong.

One possible logical solution is that the ion surface (plasmon) charge at all matter surfaces interacts and convert the speed to the local speed c each side of the transition zone (plasma is often a 'two part' phenomena). (The 'discrete field' model). No other solutions consistent with special relativity and QM have yet been proposed.