Electromagnetism: Maxwell Equations, Wave Propagation and Emission

Preface

The scientific study of electric and magnetic forces started as two distinct sciences during the second half of the 18^th Century. The concepts of electric and magnetic fields were introduced as independent constructs to facilitate the calculation of forces. However, after the discovery by Oersted in 1819 that an electric current produces a magnetic field, and the discovery by Faraday in 1831 that a variable magnetic field induces currents, it became clear that electric and magnetic fields are related and that they are very important physical concepts. In 1873, Maxwell unified electricity and magnetism in a single theory, called electromagnetism, based on four fundamental equations. An important prediction of this theory was the existence of electromagnetic waves that propagate with the speed of light. This prediction was confirmed experimentally by Hertz in 1887.

Thanks to the discovery of induction, the large-scale production of electricity became possible, opening the door to a new technological era in the second half of the 19^th Century. The discovery of electromagnetic waves and the development of electronics generated a real revolution in telecommunications in the 20^th Century with considerable economical, social, cultural and political impact.

The electromagnetic field, which is an association of the electric and magnetic fields, is a real physical object with energy, momentum, and angular momentum, which may be static or propagating as waves exactly like sound, ...