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arXiv · 2110.14963

Causal representation and numerical evaluation of multi-loop Feynman integrals

William J. Torres Bobadilla
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Abstract

The loop-tree duality (LTD) has become a novelty alternative to bootstrap the numerical evaluation of multi-loop scattering amplitudes. It has indeed been found that Feynman integrands, after the application of LTD, display a representation containing only physical information, the so-called causal representation. In this talk, we discuss the all-loop causal representation of multi-loop Feynman integrands, recently found in terms of features that describe a loop topology, vertices and edges. Likewise, in order to elucidate the numerical stability in LTD integrands, we present applications that involve numerical evaluations of two-loop planar and non-planar triangles with presence of several kinematic invariants.

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William J. Torres Bobadilla. 2021-10-28. Causal representation and numerical evaluation of multi-loop Feynman integrals. https://arxiv.org/abs/2110.14963

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