A quark cannot degenerate into a photon because they are fundamentally different types of particles with distinct properties and quantum numbers.
Quarks are elementary particles that are subject to the strong nuclear force, which is mediated by gluons. Quarks possess a property called color charge, which comes in three different types: red, green, and blue (these are just labels and have no relation to actual colors). Quarks interact with each other through the exchange of gluons, and due to the property of color confinement, they are always confined within composite particles called hadrons, such as protons and neutrons.
On the other hand, photons are elementary particles that are carriers of the electromagnetic force. They have zero mass and no electric charge. Photons do not possess color charge or participate in the strong nuclear force. They interact with charged particles, such as electrons, through the electromagnetic interaction.
The conservation of fundamental properties is a fundamental principle in particle physics. Quarks and photons have different quantum numbers, such as electric charge, color charge, and mass, and these properties are conserved during particle interactions. Therefore, a quark cannot spontaneously degenerate or transform into a photon because it would violate the conservation of these quantum numbers.
However, it's worth mentioning that quarks can emit or absorb photons through electromagnetic interactions with charged particles. This occurs, for example, in processes like Compton scattering or electron-positron annihilation, where the exchange of a photon mediates the interaction between quarks and other particles.