Fixed Points in Quantum Theories

Abstract

Exact renormalization group flow equations are treated numerically and phase structure is obtained. The phase structure of the phi^4 model is calculated. Convergence behavior of the critical exponents are investigated in two cases where Wegner-Houghton related sharp cutoff and Litim’s regulator used as N increases. Critical exponent nu is found to be 0.685399 and 0.649169 for the Wegner-Houghton and Litim’s regulator case respectively at N=10. It’s clear from the plots that in the latter situation critical exponents converge faster compared to the former situation.