TRANSFER-MATRIX METHODS IN THE BLUME-EMERY-GRIFFITHS MODEL

The critical properties of the plane Blume-Emery-Griffiths (BEG) model are analyzed using two transfer matrix approaches. The two methods and the domains of their applicability are discussed. The phase diagram is derived and compared with the one obtained by the position-space renormalization group (PSRG). The critical indices ηi and conformal anomaly c are computed at Ising-like and Potts-like critical points and a good agreement with the conformal invariance predictions is found. A new, very effective method of estimating critical points is introduced and an attempt to estimate critical end points is also made. © 1990.