On the DLR equation for the (λ:phi4:+b:phi2:+μphi, μnot =0)2 Euclidean quantum field theory: The uniqueness theorem

The Dobrushin-Lanford-Ruelle (DLR) equation is studied in a certain space of measures in the case of 2-dimensional λ:phi4:+b:phi2:+μphi, μnot =0, euclidean quantum field theory. The uniqueness theorem stating that for any μnot =0 there exists unique, translationally invariant 8-regular solution of the corresponding DLR equation is proved. The theorem is proved by combining the Lee-Yang theorem with the general van Hove type theorem for infinite volume free energy densities. copyright 1989 Academic Press, Inc