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arXiv · 2107.04558

Tree-level scattering amplitudes in nonlocal field theories

Leonardo Modesto·Gianluca Calcagni
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Abstract

We prove in two ways that, for a special class of nonlocal field theories consistent with linear and non-linear stability at the classical level, and with unitarity and super-renormalizability or finiteness at the quantum level, the $n$-point tree-level scattering amplitudes are the same as those of the underlying local theory. In particular, the $n$-point amplitudes of nonlocal gravity, with or without coupling to matter, are the same as for Einstein's general relativity.

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Leonardo Modesto, Gianluca Calcagni. 2021-07-09. Tree-level scattering amplitudes in nonlocal field theories. https://doi.org/10.1007/jhep10(2021)169

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