Since the publication of the ?rst edition of this book, we have become
deeply involved in astrophysics research, particularly the study of the
interstellar medium. Modeling scattering particles as layered spheres or
as aggregates of spherical scatterers, expanding the electromagnetic
?eld in a series of vector multipole ?elds, and resorting to the
T-matrix approach for averaging over the orientations of a dispersion of
nonspherical particles are e?ective tools for studying scattering
theory, which we described and extensively applied in the ?rst edition
of this book. In fact, these tools also proved to be adequate for
studying cosmic dust, even when they must be applied to a new range of
current problems. We refer, for example, to the description of
mechanical interaction of electromagnetic radiation with cosmic dust
grains, which is believed to be of paramount importance in determining
the dynamics of the grains. Since this book is conceived as a summary of
our work, the desire to
encompassallnewtopicsledustorevisebothitscontentanditsstructure. Of
course, beyond the changes that we outline below, all chapters were
carefully revised. Marginal changes and additions were made in Chap. 1,
while Chap. 2 has been substantially revised to cover the light of
general polarization and, in particular, with thedescription ofthestate
ofpolarization ofelectromagnetic waves of general form. In this chapter
we reserved ample space for the r- resentation of the kinematics of the
scattering processes both in the plane of scattering and in the
meridional planes.
