Is it necessary that for an E/M wave of given frequency which can pass through a medium of given refractive index, it should lose some of its intensity. Practically, this must be necessary because of imperfections in the crystal or other defects.
Also I think that if the photons collide with the nucleus, there has to be a loss in intensity, but I intend to ignore the effect of the direct collision with the nucleus which would be very small as is expected. So, are there any other reasons for intensity loss? Assume that we are talking about glass and red (monochromatic) light.
Edit: I read that glass is transparent in the visible range of light because in the visible range, photons cannot supply exactly the energy to the electrons for the electrons to absorb it and jump to a excited state. If we assume this, then a monochromatic light will either get reflected or refracted. How can both occur in the same situation?
Hence, can we choose a monochromatic light of such energy that it is less than the energy required to excite the electrons present in the material, and hence the material is unable to absorb the photons at all? (assuming complete uniformity in the crystal design of the material throughout). Hence there will be no intensity loss, theoretically.