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arXiv · 1807.08434

Two-loop D-dimensional unitarity and dual conformal symmetry

Zvi Bern·Michael Enciso·Harald Ita·Mao Zeng
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Abstract

In this talk we show that dual conformal symmetry has unexpected applications to Feynman integrals in dimensional regularization. Outside $4$ dimensions, the symmetry is anomalous, but still preserves the unitarity cut surfaces. This generally leads to differential equations whose RHS is proportional to $(d-4)$ and has no doubled propagators. The stabilizer subgroup of the conformal group leads to integration-by-parts (IBP) relations without doubled propagators. The above picture also suggested hints that led us to find a nonplanar analog of dual conformal symmetry.

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Zvi Bern, Michael Enciso, Harald Ita, Mao Zeng. 2018-07-23. Two-loop D-dimensional unitarity and dual conformal symmetry. https://arxiv.org/abs/1807.08434

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