- Photons are massless particles in the Standard Model of particle physics because they do not have any rest mass.
- Photons are the smallest and most basic unit of light and electromagnetic energy, which move at the speed of light and carry no electrical charge.
- Photons do not interact with other particles through the strong nuclear force, unlike other particles, such as protons and neutrons, which do have mass.
- Photons also do not have any inertial or gravitational mass, as they do not interact with other particles that would give them mass.
- Since photons don’t have mass, they can travel at the speed of light.