What is the theory of quantum chromodynamics?
In theoretical physics, quantum chromodynamics (QCD) is the theory of the strong interaction between quarks mediated by gluons. Quarks are fundamental particles that make up composite hadrons such as the proton, neutron and pion.
What is meant by quark confinement?
But a single quark is never found alone. Instead, when particles are smashed together and quarks are detected, they are described like ends of rubber bands that stretch, but eventually pull quarks back together again. This is known as quark confinement.
Who invented chromodynamics?
Harald Fritzsch, one of the pioneers of quantum chromodynamics, recalls some of the background to the development of the theory 40 years ago. Fig. 1.
What is quarks color charge?
Quarks have a color charge of red, green or blue and antiquarks have a color charge of antired, antigreen or antiblue. Gluons have a combination of two color charges (one of red, green, or blue and one of antired, antigreen, or antiblue) in a superposition of states which are given by the Gell-Mann matrices.
Are there anti quarks?
Antiquarks are the antiparticles of the quark, which have the opposite charge and baryon number. Antiquarks have the same mass and energy at rest as quarks.
Why are gluons confined?
Confinement. Since gluons themselves carry color charge, they participate in strong interactions. These gluon-gluon interactions constrain color fields to string-like objects called “flux tubes”, which exert constant force when stretched. Due to this force, quarks are confined within composite particles called hadrons.
What QCD means?
Quality, cost, delivery (QCD), sometimes expanded to quality, cost, delivery, morale, safety (QCDMS), is a management approach originally developed by the British automotive industry.
What are the 8 gluons?
The strong nuclear force which binds these together inside the nucleons is mediated by gluons which must carry a color-anticolor charge. This seems to give 9 types of gluon: red anti-red, red anti-blue, red anti-green, blue anti-red, blue anti-blue, blue anti-green, green anti-red, green anti-blue, green anti-green.
Does gluon have mass?
Photons, which carry the force between the electrons, are there- fore massless. In contrast to electromagnetism, the range of the strong force does not extend outside the nuclei of atoms. This fact would imply that gluons are very massive. Gluons, however, appear to be massless.