RENORMALIZATION IN TRUNCATED PARISI-SOURLAS MODEL
Keyword(s):
The Parisi-Sourlas model is truncated by ignoring irrelevant terms and introducing an N-vector field. The β-functions for the model of 4−ε dimensions are calculated up to two-loop order in the dimensional regularization scheme. By using the β-functions, the critical exponents are evaluated up to ε2-order. The critical exponents of the truncated Parisi-Sourlas model are compared with those of the ordinary N-vector model. It is found that this model roughly corresponds to the (N−2)-vector model. In fact, the ghost-like fields contribute to the critical exponents in the opposite way, being contrasted with the ordinary N-vector field.