Instantons and color symmetry breaking in the vacuum

Abstract

The instanton interaction in QCD generates an effective potential for scalar quark-antiquark condensates in the color singlet and octet channels. For three light quark flavors the cubic term in this potential induces an octet condensate and ``spontaneous breaking'' of color in the vacuum. Realistic masses of the rho- and eta'-mesons are compatible with renormalization-group-improved instanton perturbation theory.

Comments: 8 pages,LaTex,modified instanton vertex,improved mass of eta'