Precision check on triviality of phi^4 theory by a new simulation method

TL;DR

This paper introduces a new simulation method combining strong coupling expansion and random current representation to precisely study the triviality of phi^4 theory in various dimensions.

Contribution

The paper presents a novel simulation approach that enables high-precision analysis of phi^4 theory's triviality with low computational cost.

Findings

High-precision estimates of the renormalized coupling in the Ising limit.

Results for the unbroken phase in 3, 4, and 5 dimensions.

Insights into the triviality question via finite size scaling.

Abstract

We report precise simulations of phi^4 theory in the Ising limit. A recent technique to stochastically evaluate the all-order strong coupling expansion is combined with exact identities in the closely related Aizenman random current representation. In this way high precision estimates of the renormalized coupling are possible at low CPU cost. As a sample application we present results for the unbroken phase of the Ising model in dimensions 3, 4 and 5 and investigate the question of triviality by studying a finite size scaling continuum limit.