Recursive Landau Analysis

TL;DR

This paper introduces a recursive method leveraging unitarity to efficiently compute Landau singularities in n-point scattering amplitudes, advancing analysis of complex Feynman diagrams in particle physics.

Contribution

It presents a novel recursive approach for calculating Landau singularities directly in kinematic space, applicable to complex multi-loop Feynman diagrams.

Findings

Enables rapid analytic computation of Landau singularities for a broad class of diagrams.

Provides new predictions for two- and higher-loop processes in the Standard Model.

Improves upon existing methods in speed and scope of singularity analysis.

Abstract

We propose a recursive method that makes use of the basic principle of unitarity to calculate the Landau singularities of n-point scattering amplitudes directly in kinematic space. For a vast class of Feynman diagrams, the method enables rapid analytic computation of Landau singularities beyond current state-of-the-art technology. This includes new predictions relevant for two- and higher-loop processes in the Standard Model involving both massive quarks and electroweak particles.