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If visible light strikes the surface of a mirror the angle of reflection equals the angle of in incidence. The light waves, or photons must surely penetrate a silvered surface more than just the first layer of silver atoms. If so, it seems that some diffraction within those few layers of silver atoms must take place. Where can I find a treatise on this topic?

A good book to look at is "QED : The strange theory of light and matter" by R.P.Feynman. It does not address the question you have asked but several related ones, and that too at a fairly simple level.

jasjeet s bagla

Actually, it is important to remember the length scales involved here. The wavelengths of visible light are about 1000 times longer than typical spacings between atoms, so the light will penetrate at least a distance of that order. So, in fact, perfectly classical descriptions of the electric and magnetic fields in the light describe what is going on very well. Check out an advanced classical optics book, and it should discuss the principles behind reflection, refraction, and absorption in terms of the classical electromagnetic behavior, which works just fine for visible light.

Arthur Smith

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