RESONANT MULTIPLE-SCATTERING OF LIGHT

This educational work presents a new approach towards resonant interac tion between classical light and matter. The interaction between light and matter is considered from three different points of view: the lig ht picture (where the material degrees of freedom have been integrated out, and leaving one with scattering theory), the matter picture (whe re the radiative degrees of freedom have been eliminated and providing one essentially with atomic physics). In addition the polariton appro ach is discussed, in which the degrees of freedom of light and matter are treated on the same footing. Although the first approach will by f ar be given most of the attention, we will frequently emphasize the eq uivalence of the three methods. Much of the presented material is self contained.We demonstrate that in the dynamical properties of multiple scattering of light the ''matter'' properties play a dominant role. Se veral ''paradigms of atomic physics'' will be discussed from the view point of light scattering theory. We shall introduce the far-reaching analogy between the dielectric ''Mie'' sphere in classical optics, and the two-level atom in semi-classical atomic physics. This mapping tur ns out to be much more faithful than the widely used analogy between s cattering theory for De Broglie waves and classical waves. In scatteri ng theory the semi-classical two-level atom is equivalent to a point s catterer.