Standard Article

Electromagnetic Radiation

  1. Wendell T. Hill III

Published Online: 15 DEC 2009

DOI: 10.1002/3527600434.eap112.pub3

Encyclopedia of Applied Physics

Encyclopedia of Applied Physics

How to Cite

Hill, W. T. 2009. Electromagnetic Radiation. Encyclopedia of Applied Physics. 1–26.

Author Information

  1. University of Maryland, Joint Quantum Institute, Department of Physics and Institute for Physical Science & Technology, College Park, MD, USA

Publication History

  1. Published Online: 15 DEC 2009


A concise review of fundamental aspects of electromagnetic radiation, light, seasoned with references to historical developments is presented. Starting with basic definitions, this chapter gives an overview of the spectrum of light from radio waves to gamma rays, details key equations describing light propagation in vacuum, polarization, radiometric parameters, diffraction, interference, and superposition. The chapter includes a discussion of photons, the close connection between Fermat's principle for light and Maupertuis's principle for matter and concludes with a brief outline of how the wave equation for light motives Schrödinger's equation for matter waves.


  • diffraction;
  • electromagnetic spectrum;
  • interference;
  • polarization;
  • photons