Optimization of field-dependent nonperturbative renormalization group flows

TL;DR

This paper studies how the choice of momentum cutoff affects nonperturbative renormalization group flows in the 3D Ising model and demonstrates an optimization method to improve critical exponent accuracy.

Contribution

It introduces a simple optimization approach for field-dependent nonperturbative RG flows, enhancing the precision of critical exponents in the 3D Ising model.

Findings

Optimized critical exponents: ν=0.628, η=0.044

Effective optimization via the principle of minimal sensitivity

Improved accuracy in nonperturbative RG flow calculations

Abstract

We investigate the influence of the momentum cutoff function on the field-dependent nonperturbative renormalization group flows for the three-dimensional Ising model, up to the second order of the derivative expansion. We show that, even when dealing with the full functional dependence of the renormalization functions, the accuracy of the critical exponents can be simply optimized, through the principle of minimal sensitivity, which yields $\nu = 0.628$ and $\eta = 0.044$.