Cambridge University Press eBooks

Interference

Ralph F. Baierlein

Published Jun 19, 2012• 0 citations

Abstract

In making some experiments on the fringes of colors accompanying shadows, I have found so simple and so demonstrative a proof of the general law of the interference of two portions of light, which I have already endeavored to establish, that I think it right to lay before the Royal Society a short statement of the facts which appear to me so decisive. Thomas Young, Bakerian Lecture, November 24, 1803 Interference defined In chapter 3, we framed the question, can we account for the behavior of light by supposing that light is wave motion of some kind? So far, the logic of our response has been of this form: we asked experimentally, do waves have property X that we know light possesses? For “property X ,” we took the existence of reflection the equality of the angles of reflection and incidence the existence of refraction, and Snell's law, in the sense that, in refraction, the ratio of sines is independent of the angle of incidence. Each time, we could answer, yes, waves do have this property X that we know light possesses. Beyond these tests, we found that the wave theory's prediction for the index of refraction – namely, a specific ratio of wave speeds – was resoundingly confirmed by Michelson's measurements of. Things are going well for a wave theory of light. The time has come to shift the perspective and to change the logic of the testing.

DOI: 10.1017/cbo9781139170307.006

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