An Introduction to Classical Electromagnetic Radiation

This book provides the basic concepts necessary for an introduction to the classical theory of radiation. The reader is first introduced to Maxwell's equations and then led through their basic properties (Chapters 1 and 2). Non-uniform plane waves are treated in Chapter 3 with a discussion of the two and three dimensional cases. Many examples of two and three dimensional electromagnetic fields are given, and the physics of practical devices is also analysed. Geometrical rays, as well as the notion of a Gaussian beam, are introduced at this stage, and the link between electromagnetism and optical principles is amplified in Chapter 4 (the Huyghens principle, transmission through an aperture, scattering cross-section). The electromagnetic radiation from charge and current distributions is obtained in a general form from potential theory (Chapter 5), followed quite naturally by the classic illustration of the fields produced by a moving charge in the classical (v/c <<1) and relativistic (v/c~1) cases. Important physical examples (synchrotron radiation, Cherenkov radiation) are also considered in detail. The last two chapters treat the various problems associated with dipole radiation, from scattering by small objects (with, as an example, the colour and polarization of sky light) to the determination of the fields from various shapes and configurations of antenna. The reader is provided throughout all the chapters with abundant problems and examples. A much appreciated feature is the inclusion in the text, whenever necessary, of the required mathematical bases: numerical solutions of Maxwell's equation, Fourier transforms (Chapter 1), the stationary phase method (Chapter 3), the Dirac function (Chapter 5) and a review of vector analysis (Annex B). These mathematical sections will be specially useful for advanced undergraduates who may need some mathematical tools and, thus, will not need to search for these in more specialized books. The main focus of the book is to provide the reader with the fundamentals of the classical theory of radiation. This aim is well complemented by examples from a variety of fields. Since the purpose of the book is not to provide a general treatment of electromagnetism or electrodynamics, the reader cannot expect to find some of the topics usual in other electrodynamics texts, such as relativistic transforms of electromagnetic fields (although the Lorentz condition is mentioned) or a discussion of the causality principle in the derivation of the Green function. However, within the scope of the book, these topics are not essential for an understanding of electromagnetic radiation and can therefore be omitted. I feel that the author has covered the essentials of the subject of electromagnetic radiation. The reader, even the advanced undergraduate, will be able to follow the mathematical steps, as well as the physical insights. A historical introduction (paragraphs 1.1 and 2.7) also broadens the reader's knowledge of the field, a feature rarely found in other texts. The large number of figures and the numerous examples also facilitate the reading of the book. This book appears to me to be a very useful textbook that is accessible to a very broad category of readers, from advanced undergraduates to researchers, since it starts with the basic physics and covers quite extensively the field of electromagnetic radiation. For a reader who is interested in electromagnetism and electrodynamics, it is an excellent companion to the classical and more fundamental text books, such as Jackson's Classical Electrodynamics, Landau and Lifshitz's The Classical Theory of Fields or Stratton's Electromagnetics Theory. In summary, I heartily recommend this book, An Introduction of Classical Electromagnetic Radiation, to all my colleagues who teach the subject of electromagnetic radiation, to students who follow such courses and to researchers active in this field.