|physics QCD a theory describing the strong interaction in terms of quarks and gluons, with the colour of quarks used as an analogue of charge and the gluon as an analogue of the photon|
|[C20: chromodynamics from |
A quantum field theory of the strong force that explains the interaction between particles with color charge, such as quarks and gluons. In quantum chromodynamics, particles interact through the strong force by exchanging gluons, which are the carriers of the strong force (much as photons are the carriers of the electromagnetic force in quantum electrodynamics). The theory is particularly important in theories of the atomic nucleus, whose nucleons are composed of quarks.