Recent Progress of Lattice Qcd in China

Particle physics and gauge field theories are frontiers of fundamental sciences of matter. According to Yang and Mills, any basic theory of interacting matter should satisfy gauge invariance. QCD has been accepted to be the most successful gauge theory of strongly interacting particles. In QCD, hadronic matter is composed of quarks, and interactions between them are mediated by eight massless gluons generated by the SU(3) gauge group. Asymptotic freedom of QCD at short distances makes the perturbative calculations of high-energy processes possible. At low energy scales, however, QCD has many important properties which can not be studied perturbatively, like confinement of quarks and gluons, vacuum structure, chiral-symmetry breaking, glueball masses, hadronic spectrum and weak interaction processes, and behaviors of hadronic matters at high temperature or high density. Lattice gauge theory (LGT) has developed into a promising first principle non-perturbative approach to these phenomena. The basic idea , as proposed by K. Wilson in 1974, is to replace the continuous space and time by a discrete grid: