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arXiv · 2203.17057

Scaling exponents of Mellin amplitudes for deriving bounds on flat space S-matrices from bounds on chaos

Mitsuhiro Nishida
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Abstract

We study an inequality between a scaling exponent $A$ in the Regge limit of tree-level flat space S-matrices with external massless scalars and another scaling exponent $A'$ in the Regge limit of the corresponding four-point scalar conformal correlators by using scaling exponents of Mellin amplitudes. We derive $A'\ge A$, which leads to the Regge growth bound of tree-level flat space S-matrices from the chaos bound in the flat space limit of the AdS/CFT correspondence, from polynomial boundedness of the Mellin amplitudes for local bulk descriptions. We also show $A'=A$ from the conformal block expansion in the $t$-channel with finite intermediate spins when coefficients are not small in the flat space limit.

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Mitsuhiro Nishida. 2022-03-31. Scaling exponents of Mellin amplitudes for deriving bounds on flat space S-matrices from bounds on chaos. https://arxiv.org/abs/2203.17057

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