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arXiv · 1909.04055

Triangle diagram, Distance Geometry and Symmetries of Feynman Integrals

Barak Kol·Subhajit Mazumdar
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Abstract

We study the most general triangle diagram through the Symmetries of Feynman Integrals (SFI) approach. The SFI equation system is obtained and presented in a simple basis. The system is solved providing a novel derivation of an essentially known expression. We stress a description of the underlying geometry in terms of the Distance Geometry of a tetrahedron discussed by Davydychev-Delbourgo [1], a tetrahedron which is the dual on-shell diagram. In addition, the singular locus is identified and the diagram's value on the locus's two components is expressed as a linear combination of descendant bubble diagrams. The massless triangle and the associated magic connection are revisited.

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Barak Kol, Subhajit Mazumdar. 2020-04-15. Triangle diagram, Distance Geometry and Symmetries of Feynman Integrals. https://doi.org/10.1007/jhep03(2020)156

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