Magic Relations and Critical Varieties of Feynman Integrals
Abstract
Magic relations are a class of integration-by-parts identities where all integrals in the generating sector drop out. Since their presence causes several otherwise successful methods in the Feynman-integral computational pipeline to break down, they are important to detect and understand. In this paper, we take a first step toward a systematic characterization of such identities. Specifically, we observe and argue that the occurrence of magic relations always coincides with the presence of higher-dimensional critical varieties in the generating sector. This provides a practical computational test to check if a family of Feynman integrals can contain magic relations and to find them, which we implement in the ancillary Mathematica file Magic-Test.m. Additionally, we discuss how to count the number of master integrals in the presence of higher-dimensional critical varieties, classify the behavior of magic relations under symmetries, and we discuss their interplay with cuts.
Comments: 44 pages, 4 figures
Cite
@article{arxiv.2605.29789,
title = {Magic Relations and Critical Varieties of Feynman Integrals},
author = {Giulio Crisanti and Hjalte Frellesvig and Andrzej Pokraka and Sid Smith},
journal= {arXiv preprint arXiv:2605.29789},
year = {2026}
}