Tropical sampling from Feynman measures

Michael Borinsky; Mathijs Fraaije

doi:10.1016/j.cpc.2025.109846

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arXiv · 2504.09613

Tropical sampling from Feynman measures

Michael Borinsky·Mathijs Fraaije

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Abstract

We introduce an algorithm that samples a set of loop momenta distributed as a given Feynman integrand. The algorithm uses the tropical sampling method and can be applied to evaluate phase-space-type integrals efficiently. We provide an implementation, momtrop, and apply it to a series of relevant integrals from the loop-tree duality framework. Compared to naive sampling methods, we observe convergence speedups by factors of more than $10^6$.

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Michael Borinsky, Mathijs Fraaije. 2025-04-13. Tropical sampling from Feynman measures. https://doi.org/10.1016/j.cpc.2025.109846

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