Photon

Discrete bundle of light energy. Light of a given energy (frequency) cannot be broken up indefinitely. Rather for a given frequency it comes in discrete bundles with energy (h = Planck’s constant and ν= frequency):

It is often useful to think of light as a bunch of particle photons; whereas, at other times it is useful to think of light as a wave. This is termed the “wave-particle duality.” The idea of the photon was advanced by Albert Einstein in his theory of the photoelectric effect.


Some or all content above used with permission from J. H. Wittke.