"graviton." YourDictionary, n.d. Web. 06 December 2018. <https://www.yourdictionary.com/graviton>.
graviton. (n.d.). Retrieved December 06th, 2018, from https://www.yourdictionary.com/graviton
A hypothetical particle postulated in supergravity theory to be the quantum of gravitational interaction, mediating the gravitational force. Like all force carriers, the graviton is a boson. It is presumed to have an indefinitely long lifetime, zero electric charge, a spin of 2, and zero rest mass (thus travelling at the speed of light). The graviton has never been detected.