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arXiv · 2402.04150

Soft Algebras for Leaf Amplitudes

Walker Melton·Atul Sharma·Andrew Strominger
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Abstract

Celestial MHV amplitudes are comprised of non-distributional leaf amplitudes associated to an AdS$_3$ leaf of a foliation of flat spacetime. It is shown here that the leaf amplitudes are governed by the same infinite-dimensional soft `$S$-algebra' as their celestial counterparts. Moreover, taking the soft limit of the smooth three-point MHV leaf amplitude yields a nondegenerate minus-minus two-point leaf amplitude. The two- and three-point MHV leaf amplitudes are used to compute the plus-minus-minus leaf operator product coefficients.

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Walker Melton, Atul Sharma, Andrew Strominger. 2024-02-06. Soft Algebras for Leaf Amplitudes. https://arxiv.org/abs/2402.04150

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