American Journal of Physics

About the statistical meaning of group velocity

Wencheng Wang, Cheng-Ming Chen

Published Aug 1, 1990• 3 citations

Abstract

The propagation velocity of light in a medium is the transport velocity of the energy. According to the theory of wave motion, this velocity is also the group velocity of light. But, by using quantum theory, it is proved that the group velocity is not the instantaneous velocity of a photon, but rather the statistical average velocity of photons in a medium.

DOI: 10.1119/1.16397

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