UNIVERSALITY FOR INTERACTING ORIENTED SELF-AVOIDING WALK - A TRANSFER-MATRIX CALCULATION

In this paper we perform transfer matrix calculations to study the two -dimensional problem of oriented self-avoiding walks on a square latti ce where nearest neighbor interactions depend on the relative orientat ion (parallel or antiparallel) between different parts of the path. Ou r main purpose is to verify a conformal field theory conjecture that t he entropic exponent gamma, which is related to the number of such wal ks, varies continuously with the energy of the parallel interaction. W e find no evidence of this behavior, but see many unexpected features for the model, such as the existence of a line of a points belonging t o the universality class of polymer collapse on a Manhattan lattice. F inally we study the phase diagram in the parallel and antiparallel int eraction planes and we conjecture a crucial role for the standard a po int.