Abstract

A new formalism to calculate the in-medium chiral condensate is presented. At lower densities, this approach leads to a linear condensate. If it is compatible with the famous model-independent result, the pion-nucleon sigma term could be six times the average current mass of light quarks. The modification due to QCD-like interactions may, compared with the linear extrapolation, slow the decreasing speed of the condensate with increasing densities. © 2002 Published by Elsevier Science B.V.