BEIJING UNIV,DEPT TECH PHYS,BEIJING 100871,PEOPLES R CHINA
; ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING 100039,PEOPLES R CHINA
; BEIJING UNIV,DEPT PHYS,BEIJING,PEOPLES R CHINA
We developed the MIT bag crystal model for nuclear matter in two aspects. First, we proved a DELTAmu=4 selection rule in the harmonic expansion of quark wave function by group theory. It enables us to push the maximum Dirac quantum number kappa(m) up from 7 to 15, therefore improving our calculation for the energy band and wave functions of quarks. Then, by a multipole expansion of the color fields we calculate the color interaction energy between quarks. These developments enable us to calculate the energy per nucleon in nuclear matter as done previously for a free nucleon. A nuclear equation of state is derived.