Describes the use of free-electron lasers as a source of coherent radiation over a broad range of wavelengths from the far-infrared to the far-ultraviolet regions of the spectrum. Discusses some applications of these lasers, including medicine and strategic defense. (TW)

Discusses refraction in terms of the deviation of light. Points out that in physics courses where very little mathematics is used, it might be more suitable to describe refraction entirely in terms of the deviation, rather than by introducing Snell's law. (DH)

A retroreflector is a mirror that removes distortion from a light beam. Describes experiments using the retroreflector as well as related phenomena. (JN)

This book is designed to help teachers bolster their content knowledge by focusing on specific science concepts regarding the topic of light. The book covers three scientific models of light and discusses the observations that can be explained by each model. Chapters include: (1) "LightN-The Early Years"; (2) "Colorful Waves"; (3) "Focus, People,…

A discussion of the possible existence of tachyons, particles that travel faster than light, and their theoretical properties. Suggests that if tachyons were found, the consequences for relativity theory, quantum mechanics and the concept of casuality would be far-reaching. Concludes that the final answer rests with the experimentalist.…