Calculation of critical pomeron intercept with block-spin methods

Abstract

The single-site energy eigenvalues and field matrix elements of reggeon field theory are accurately calculated. Using the block-spin approximation with realistic parameters, the phase transition is studied in one and two dimensions using different methods. In one dimension, the use of blocks with one site and one link gives a critical temperature in agreement with that predicted by the high-temperature expansion. In two dimensions, the methods with critical temperature around the high-temperature expansion result, give a critical pomeron intercept larger than 1.05 in the physical range.