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arXiv · 2303.02125

One-loop calculations in the chirality-flow formalism

Andrew Lifson·Simon Plätzer·Malin Sjodahl
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Abstract

In a few recent papers we introduced the chirality-flow formalism, which was shown to make calculations of tree-level Feynman diagrams simple and transparent. Chirality flow, which is based on the spinor-helicity formalism, allows to often immediately analytically write down a tree-level Feynman diagram in terms of spinor inner products. In this paper, we argue that there is also a significant simplification of the Lorentz structure at the one-loop level, at least when using the four-dimensional formulation of the four-dimensional helicity scheme. Additionally, we find that the possible terms in a tensor decomposition of loop integrals are highly constrained, and therefore the tensor reduction procedure is simplified.

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Andrew Lifson, Simon Plätzer, Malin Sjodahl. 2023-03-03. One-loop calculations in the chirality-flow formalism. https://arxiv.org/abs/2303.02125

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