Classical Electrodynamics

Electromagnetic theory is one of the fundamental pillars of physics, providing the framework for understanding electric and magnetic fields and their interactions. It is essential not only for classical physics but also for modern advancements in engineering, communications, and quantum mechanics. This chapter introduces the historical development of electrodynamics and the significance of Maxwell’s equations, which form the foundation of classical electromagnetism. The origins of electromagnetic theory can be traced back to early observations of static electricity and magnetism. The ancient Greeks, particularly Thales of Miletus, noted that rubbing amber could attract small objects, laying the groundwork for electrostatics. By the 17th century, William Gilbert’s studies on magnetism and Benjamin Franklin’s experiments on electricity further developed the understanding of electric and magnetic phenomena. The 18th and 19th centuries saw rapid progress, with Charles-Augustin de Coulomb formulating the inverse-square law of electrostatics and André-Marie Ampère discovering the relationship between current and magnetic fields. Michael Faraday’s groundbreaking work on electromagnetic induction demonstrated that a changing magnetic field could induce an electric current, setting the stage for the unification of electricity and magnetism.