ABSTRACT
Particles and gases absorb and scatter radiation spectrally, and without detailed understanding of the wave nature of light, it will be impossible to determine their optical properties and their contributions to the radiative energy balance. In addition, as the object sizes get smaller, as is the case of micro-and nanoscale objects, the EM wave propagation needs to be considered in detail to calculate the energy exchange between them. Only with the use of EM theory can we consider polarization, coherence, and radiation tunneling, along with the propagation of radiative energy between such structures. In this chapter, we provide the general expressions for the EM wave theory and consider their use for determining surface properties. Finally, we briežy describe how the EM theory can be used to derive the RTE.
