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arXiv 2003.058772020-03hep-phhep-th

The chirality-flow formalism

Andrew Lifson, Christian Reuschle, Malin Sjodahl

备注：: 44 pages, 3 figures; Version accepted by EPJC. Minor typo corrections
发表信息：: Eur. Phys. J. C 80, 1006 (2020)
DOI：: 10.1140/epjc/s10052-020-8260-8

英文摘要：

We take a fresh look at Feynman diagrams in the spinor-helicity formalism. Focusing on tree-level massless QED and QCD, we develop a new and conceptually simple graphical method for their calculation. In this pictorial method, which we dub the chirality-flow formalism, Feynman diagrams are directly represented in terms of chirality-flow lines corresponding to spinor inner products, without the need to resort to intermediate algebraic manipulations.

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