Universal sextic effective interaction at criticality
A. I. Sokolov, E. V. Orlov, V. A. Ul’kov
Abstract
The renormalization group approach in three dimensions is used to estimate the universal critical value of dimensionless sextic effective coupling constant for the Ising model. Four–loop expansion for g6 is calculated and resummed resulting in g ∗ 6 = 1.596, while the most accurate estimate for g ∗ 6 is argued to be equal to 1.61. 1 The critical thermodynamics of the three–dimensional Ising model is known to be described by Euclidean scalar field theory with the Hamiltonian H =