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  • Letter
  • Open Access

Landau singularities from Whitney stratifications

Martin Helmer1, Georgios Papathanasiou2,3,4,*, and Felix Tellander4,5,6,†

  • *Contact author: g.papathanasiou@phys.uoa.gr
  • †Contact author: felix@tellander.se
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Phys. Rev. D 114, L011901 – Published 6 July, 2026

DOI: https://doi.org/10.1103/8tk7-3gkn

Abstract

We demonstrate that the complete and nonredundant 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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  36. We thank Erik Panzer for confirming this.

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Outline

Information

Phys. Rev. D 114, L011901– Published 6 July, 2026
  • Received 24 July 2024
  • Accepted 26 May 2026
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