Nonperturbative renormalization group approach to the Ising model: a derivative expansion at order $\partial^4$

TL;DR

This paper uses a nonperturbative renormalization group method with a derivative expansion at order  to accurately compute critical exponents for the 3D Ising model, improving previous results.

Contribution

It introduces a th order derivative expansion in the nonperturbative RG approach to enhance the precision of critical exponent calculations for the Ising model.

Findings

Critical exponent  = 0.632

Anomalous dimension ta = 0.033

Significant improvement over lower-order calculations

Abstract

On the example of the three-dimensional Ising model, we show that nonperturbative renormalization group equations allow one to obtain very accurate critical exponents. Implementing the order $\partial^4$ of the derivative expansion leads to $\nu=0.632$ and to an anomalous dimension $\eta=0.033$ which is significantly improved compared with lower orders calculations.