Studies in the field of light radiation

✍ Scribed by Charles Fabry

• Book ID: 104123407
• Publisher: Elsevier Science
• Year: 1921
• Tongue: English
• Weight: 755 KB
• Volume: 192
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/s0016-0032(21)90715-4

✦ Synopsis

THE direct study of the phenomena of light, independently of any hypothesis, leads to the following conclusion: " Light is produced by a periodic phenomenon which is propagated."

Every radiation, however complex it may be, may be decomposed into a certain number, finite or infinite, of such periodic disturbances ; each of these is the simple element of every radiation. I propose to give in what follows a review of the researches, carried on since the days of Newton, which have led to the discovery of all possible types of radiation, and have made this subject one of the most immense fields of study that can be met in physics.

Let us recall the essential elements characterizing every propagation of a periodic phenomenon. They are three in number : I. The period is the essential element of every periodic phenomenon, and is independent of the mode of propagation. The number of periods per second, i.e., the frequency, can also serve to characterize this element;

2. The velocity, on the contrary, characterizes the propagation, independently of any idea of periodicity;

3-From the periodicity in time and the uniform propagation in space results a periodicity in space, characterized by the wavelength, i.e., the distance the disturbance is propagated during one * Presented at the Stated Meeting of the Institute held Wednesday, May I8, I92I.