Field-theoretic techniques and critical dynamics. I. Ginzburg-Landau stochastic models without energy conservation

Abstract

Renormalization techniques of field theory are used to prove (order by order to all orders) dynamical scaling laws on a Ginzburg-Landau stochastic model studied by Halperin, Hohenberg, and Ma. The dynamical exponent is calculated to order ${\epsilon }^3$ and so is the new exponent ${\omega }_b$, which governs the vanishing of the imaginary part of the (renormalized) kinetic coefficient, and appears among the corrections to scaling. Difficulties of previous calculations taking a microscopic approach to the critical dynamics of a Bose system are commented upon.