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arXiv · 2402.14787

Landau Singularities from Whitney Stratifications

Martin Helmer·Georgios Papathanasiou·Felix Tellander
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Abstract

We demonstrate that the complete and non-redundant set of Landau singularities of Feynman integrals may be explicitly obtained from the Whitney stratification of a certain map. As a proof of concept, we leverage recent theoretical and algorithmic advances in their computation in order to determine this set for nontrivial examples of two-loop integrals. Interestingly, different strata of the Whitney stratification describe not only the singularities of a given integral, but also those of integrals obtained from kinematic limits, e.g. by setting some of its masses or momenta to zero.

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Martin Helmer, Georgios Papathanasiou, Felix Tellander. 2024-02-22. Landau Singularities from Whitney Stratifications. https://arxiv.org/abs/2402.14787

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