Decoupling of pion coupling f_(π) from quarks at high density in three models, and its possible observational consequences

Chiral symmetry is restored at high density, quarks become nearly massless and pion, the Goldstone of the symmetry breaking decouples from the quarks. What happens at high density is important for finding the density dependence of Strange Quark Matter (SQM), - which in turn is relevant for understanding the structure of compact stars.