Boson

Boson, one of the 4 major classes of elementary particles (the others being the leptons, mesons, and baryons). The bosons have no mass. They include photons, gluons, and, hypothetically, the graviton. Bosons were named for the Indian physicist Satyendranath Bose, who with Albert Einstein developed a statistical theory of the behavior of these particles in the 1920s.

See also: Particle physics.