Science Education

Early theories on the nature of heat and light

Ned D. Heindel, Nancy C. Warner

Published Mar 1, 1969• 0 citations

Abstract

Abstract Though no simple picture has been invented affording a mechanical model of a light ray, by combining the notions of waves and particles a logically consistent theory has been devised which seems essentially capable of accounting for the properties of light as we know them. Radio rays, heat rays, visible and ultra‐violet light, X‐rays, gamma rays and cosmic rays all are thus different varieties of light. We find from our experiments on diffraction and interference that light consists of waves. The photoelectric effect and the scattering of X‐rays give equally convincing reasons for believing that light consists of particles. For centuries it has been supposed that the two conceptions are contradictory. Goaded on, however, by obstinate experiments we seem to have found a way out. We continue to think of light propagated as electromagnetic waves; but whenever the light does something, it does it as photons. In reply to our question, what is light, the answer seems to come, waves and particles, light is both.

DOI: 10.1002/sce.3730530210

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