Using Feynman's Tree Theorem to Evaluate Loop Integrals Numerically

TL;DR

This paper introduces a novel numerical method for evaluating loop integrals in quantum field theory using Feynman's Tree Theorem, enabling efficient NLO event generation through phase-space integration.

Contribution

The paper presents a new approach that replaces loop integrals with phase-space integrals over on-shell particles, facilitating direct NLO event simulation.

Findings

Method successfully computes loop integrals numerically.

Enables combined phase-space and loop integration for NLO events.

Improves efficiency of higher-order quantum calculations.

Abstract

We report on a new method for the numerical evaluation of loop integrals, based on the Feynman Tree Theorem. The loop integrals are replaced by phase-space integration over fictitious extra on-shell particles. This integration can be performed alongside with the Monte-Carlo integration of ordinary phase-space, directly leading to NLO event generation.