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arXiv · 1512.06801

Recursion relations from soft theorems

Hui Luo·Congkao Wen
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Abstract

We establish a set of new on-shell recursion relations for amplitudes satisfying soft theorems. The recursion relations can apply to those amplitudes whose additional physical inputs from soft theorems are enough to overcome the bad large-z behaviour. This work is a generalization of the recursion relations recently obtained by Cheung et al for amplitudes in scalar effective field theories with enhanced vanishing soft behaviours, which can be regarded as a special case of those with non-vanishing soft limits. We apply the recursion relations to tree-level amplitudes in various theories, including amplitudes in the Akulov-Volkov theory, amplitudes containing dilatons of spontaneously-broken conformal symmetry.

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Hui Luo, Congkao Wen. 2016-03-02. Recursion relations from soft theorems. https://doi.org/10.1007/jhep03(2016)088

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