MEAN-FIELD, INSTANTONS AND FINITE BARYON DENSITY

Instantons create a non-local interaction between the quarks, which at finite baryon density leads to the formation of a scalar diquark cond ensate and color superconductivity. A mean field approach leads to a s elf-consistent description of the [(q) over bar q] and [qq] condensate s and shows the inevitability of a BCS type instability at the Fermi s urface. The role of the rearrangement of the instanton ensemble for th e QCD phase transitions is also discussed.