The gluon holds together quarks to form protons and neutrons. Mills equations for quark and gluon fields. Photon energy and gluon energy are also carried by massless particles. It consists solely of gluon particles, without valence quarks. The force carrier particle of the strong interaction is the gluon, a massless boson. Hadrons with explicit valence gluon content would also be considered exotic. Gluon field configurations called instantons are closely related to this anomaly. The particle that carries the strong nuclear force is thought to be a gluon. The gluon is a particle with a spin of 1. Also in 1976, he published two papers suggesting techniques for finding the gluon in annihilations. The gluon has negative intrinsic parity. Wu was a key contributor to the discovery of gluon. These are the "color labels" on the gluon. Each gluon carries one color charge and one anticolor charge.