This book provides an understanding of the theoretical foundations for
the calculation of electromagnetic processes. Photon production
processes are particularly important in astrophysics, since almost all
of our knowledge of distant astronomical objects comes from the
detection of radiation from these sources. Further, the conditions
therein are extremely varied and a wide variety of naturally occurring
electromagnetic phenomena can be described by limiting forms of the
basic theory.
The first chapter reviews some basic principles that are the
underpinnings for a general description of electromagnetic phenomena,
such as special relativity and, especially, relativistic covariance.
Classical and quantum electrodynamics (QED) are then formulated in the
next two chapters, followed by applications to three basic processes
(Coulomb scattering, Compton scattering, and bremsstrahlung). These
processes are related to other phenomena, such as pair production, and
the comparisons are discussed.
A unique feature of the book is its thorough discussion of the
nonrelativistic limit of QED, which is simpler than the relativistic
theory in its formulation and applications. The methods of the
relativistic theory are introduced and applied through the use of
notions of covariance, to provide a shorter path to the more general
theory. The book will be useful for graduate students working in
astrophysics and in certain areas of particle physics.