Feynman Integral Reduction and Landau Singularities
Federico Coro, Pavel P. Novichkov, Ben Page, Qian Song
TL;DR
The paper tackles the computational challenge of Feynman integral reduction by linking syzygy relations to Landau singularities through the Baikov representation. It develops a Landau-decomposition framework that expresses the critical syzygy module as a sum over Landau-geometry components, implemented via a determinantal, saturation-based construction of Fitting syzygies. The approach is demonstrated on two-loop, five-point examples, including the double-box and a pentabox family relevant to $pp \rightarrow t\\overline{t}H$, showing compact analytic generators organized by infrared loci and enabling cross-topology reuse. This provides a physically transparent reduction mechanism with potential for stable, efficient computations in high-precision collider amplitudes.
Abstract
We propose that Feynman integral reduction is controlled by solutions of the Landau equations. We study integral relations with prescribed propagator powers using syzygy methods and discuss how syzygies can be expressed as a sum over components of the Landau singularity locus. This leads to a determinantal approach to solving the syzygy problem, giving rise to highly compact and physically transparent solutions. We demonstrate the method in applications to planar two-loop five-point integrals relevant for the $pp \rightarrow t\overline{t}H$ process. Our results suggest an efficient method of Feynman integral reduction and provide a novel physical perspective on the problem.
