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arXiv · 1706.01486

Curvature-Squared Multiplets, Evanescent Effects and the U(1) Anomaly in N = 4 Supergravity

Zvi Bern·Alex Edison·David Kosower·Julio Parra-Martinez
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Abstract

We evaluate one-loop amplitudes of N = 4 supergravity in D dimensions using the double-copy procedure that expresses gravity integrands in terms of corresponding ones in Yang--Mills theory.We organize the calculation in terms of a set of gauge-invariant tensors, allowing us to identify evanescent contributions. Among the latter, we find the matrix elements of supersymmetric completions of curvature-squared operators. In addition, we find that such evanescent terms and the U(1)-anomalous contributions to one-loop N = 4 amplitudes are tightly intertwined. The appearance of evanescent operators in N = 4 supergravity and their relation to anomalies raises the question of their effect on the known four-loop divergence in this theory. We provide bases of gauge-invariant tensors and corresponding projectors useful for Yang--Mills theories as a by-product of our analysis.

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Zvi Bern, Alex Edison, David Kosower, Julio Parra-Martinez. 2017-06-05. Curvature-Squared Multiplets, Evanescent Effects and the U(1) Anomaly in N = 4 Supergravity. https://doi.org/10.1103/physrevd.96.066004

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