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arXiv · 2312.06759

Five-point Superluminality Bounds

Francesco Serra·Leonardo G. Trombetta
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Abstract

We investigate how the speed of propagation of physical excitations is encoded in the coefficients of five-point interactions. This leads to a superluminality bound on scalar five-point interactions, which we present here for the first time. To substantiate our result, we also consider the case of four-point interactions for which bounds from S-matrix sum rules exist and show that these are parametrically equivalent to the bounds obtained within our analysis. Finally, we extend the discussion to a class of higher-point interactions.

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Francesco Serra, Leonardo G. Trombetta. 2023-12-11. Five-point Superluminality Bounds. https://doi.org/10.1007/jhep06(2024)117

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