Modifying partition functions: a way to solve the sign problem

TL;DR

The paper proposes a method to address the sign problem by modifying the partition function and reconstructing observables, demonstrated on a simple 1D integral.

Contribution

It introduces a novel approach of modifying the partition function to solve the sign problem and reconstruct original observables.

Findings

Method yields correct results despite severe sign problems

Applicable to theories with complex sign issues

Validated on a simple 1D integral

Abstract

A possible method to solve the sign problem is developed by modifying the original theory. Considering several modifications of the partition function, the observable in the original theory is reconstructed from the identity connecting the observables in the original and modified theories. We demonstrate that our method gives the correct results even if the original theory has the severe sign problem by using a simple 1-dimensional integral.