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arXiv · 2204.03190

Universal Treatment of Reduction for One-Loop Integrals in Projective Space

Bo Feng·Jianyu Gong·Tingfei Li
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Abstract

Recently a nice work about the understanding of one-loop integrals has been done in [1] using the tricks of the projective space language associated to their Feynman parametrization. We find this language is also very suitable to deal with the reduction problem of one-loop integrals with general tensor structures as well as propagators with arbitrary higher powers. In this paper, we show that how to combine Feynman parametrization and embedding formalism to give a universal treatment of reductions for general one-loop integrals, even including the degenerated cases, such as the vanishing Gram determinant. Results from this method can be written in a compact and symmetric form.

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Bo Feng, Jianyu Gong, Tingfei Li. 2022-05-19. Universal Treatment of Reduction for One-Loop Integrals in Projective Space. https://doi.org/10.1103/physrevd.106.056025

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