X-rays: a century of discovery, diffraction, and dynamical theory
The International Year of Light provides a good opportunity to revisit the early studies on the optical properties of X-rays. X-rays were discovered by W. C. Röntgen on the evening of 8 November 1895 while he was redoing some of Hertz’s experiments on cathode rays. By the end of the year, even before informing the world of his discovery, he had observed the basic properties of X-rays: like light, they propagate as straight lines and are diffused by turbid media, but are not deflected by a prism, nor refracted or reflected by matter; they pass through bodies, as shown by the radiograph of his wife’s hand.