Photon

Name:
Photon
Detailed information:
The unit (quantum) of electromagnetic radiation. Light waves, γ rays, X rays, etc. consist of photons. Photons are discrete concentratiosn of energy that seem to have no rest mass and move at the speed of light. Their nature can be described only in mathematical terms. Photons are emitted when electrons move from one energy state to another, as in an excited atom.See Radiation.