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arXiv · 1703.04403

Analytic expressions of amplitudes by the cross-ratio identity method

Kang Zhou
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Abstract

In order to obtain the analytic expression of an amplitude from a generic CHY-integrand, a new algorithm based on the so-called cross-ratio identities has been proposed recently. In this paper, we apply this new approach to a variety of theories including: non-linear sigma model, special Galileon theory, pure Yang-Mills theory, pure gravity, Born-Infeld theory, Dirac-Born-Infeld theory and its extension, Yang-Mills-scalar theory, Einstein-Maxwell theory as well as Einstein-Yang-Mills theory. CHY-integrands of these theories which contain higher-order poles can be calculated conveniently by using the cross-ratio identity method, and all results above have been verified numerically.

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Kang Zhou. 2017-03-13. Analytic expressions of amplitudes by the cross-ratio identity method. https://doi.org/10.1140/epjc%2Fs10052-017-4941-3

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