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How do gluons differ from photons?

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subatomic particle The Large Hadron Collider (LHC), the world's most powerful particle accelerator. At the LHC, located underground in Switzerland, physicists study subatomic particles.

While both gluons and photons are massless gauge bosons with a spin of 1 that mediate fundamental forces, they differ significantly in their interactions and properties.123

The primary distinction lies in their charge:
* Photons are electrically neutral and do not carry electric charge. Consequently, they do not interact directly with one another.234
* Gluons carry a "strong charge" known as colour. Because they possess this charge, gluons can interact with each other through the strong nuclear force.124

These differences have profound physical consequences. While the electromagnetic force mediated by photons can extend across infinite distances, the self-interaction of gluons limits the range of the strong force to approximately $10^{- 15}$ metres. This self-interaction is also responsible for the confinement of quarks within composite particles like protons and neutrons, as gluons prevent colour-charged particles from being isolated in nature.2345