light quantum

noun

Physics.

1. photon.

Word History and Origins

Origin of light quantum¹

First recorded in 1920–25

Example Sentences

At the same time, Einstein defined a new entity: a particle of light, the “light quantum,” now called the photon.

From New York Times

“There is no definite information on the length of time elapsing during the process of absorption of a quantum of energy photo-electrically by an electron,” they reported, “and the so-called length of a light quantum—if such a concept has meaning—is equally unknown experimentally.”

From Literature

Himself a founding father of the early quantum theory and author of the light quantum hypothesis, he sensed that here was a problem that could not be reconciled with classical concepts and imperatively required new ideas and approaches.

From Scientific American

Relativity deals with time, space, gravity, the finite speed of light; quantum mechanics with particles, electricity, the action of light.

From Time Magazine Archive