Well I read [1] [2] that they do have gravity... which is probably a more direct answer to what you're asking. I'm not sure what counts as "mass" for a photon p

Well I read [1] [2] that they do have gravity... which is probably a more direct answer to what you're asking. I'm not sure what counts as "mass" for a photon per se, except that I assume there's an effective mass via the energy. [1] https://www.quora.com/How-does-a-photon-exert-gravitational-pull/answer/Giordon-Stark https://www.quora.com/How-does-a-photon-exert-gravitational-... [2] https://physics.stackexchange.com/a/22878 https://physics.stackexchange.com/a/22878