Renormalization-group description of nonequilibrium critical short-time relaxation processes: A three-loop approximation

摘要

The influence of nonequilibrium initial values of the order parameter on its evolution at a critical point is described using a renormalization group approach of the field theory. The dynamic critical exponent theta of the short time evolution of a system with an n-component order parameter is calculated within a dynamical dissipative model using the method of epsilon-expansion in a three-loop approximation. Numerical values of theta for three-dimensional systems are determined using the Pade-Borel method for the summation of asymptotic series.