We study the effective potential of three-dimensional O(N) models. In statistical physics the effective potential represents the free-energy density as a function of the order parameter (Helmholtz free energy), and, therefore, it is related to the equation of state. In particular, we consider its small-field expansion in the symmetric (high-temperature) phase, whose coefficients are related to the zero-momentum 2j-point renormalized coupling constants g(2j). For generic values of N, we calculate g(2j) to three loops in the field-theoretic approach based on the E-expansion. The estimates of g(2j), or equivalently of r(2j) = g(2j)/g(4)(j-1), are obtained by a constrained analysis of the series that takes into account the exact results in one and zero dimensions. (C) 2000 Elsevier Science B.V. All rights reserved.
The effective potential of N-vector models: a field-theoretic study to O(epsilon(3))
VICARI, ETTORE
2000-01-01
Abstract
We study the effective potential of three-dimensional O(N) models. In statistical physics the effective potential represents the free-energy density as a function of the order parameter (Helmholtz free energy), and, therefore, it is related to the equation of state. In particular, we consider its small-field expansion in the symmetric (high-temperature) phase, whose coefficients are related to the zero-momentum 2j-point renormalized coupling constants g(2j). For generic values of N, we calculate g(2j) to three loops in the field-theoretic approach based on the E-expansion. The estimates of g(2j), or equivalently of r(2j) = g(2j)/g(4)(j-1), are obtained by a constrained analysis of the series that takes into account the exact results in one and zero dimensions. (C) 2000 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
