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arXiv · 2308.02847

Saturating unitarity bounds at U-duality symmetric points

Guillaume Bossard·Adrien Loty
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Abstract

It has recently been shown that the leading Wilson coefficient in type II string theory can take (almost) all values allowed by unitarity, crossing symmetry and maximal supersymmetry in D=10 and D=9 dimensions. This suggests that string theory might define the unique consistent quantum theory of gravity with maximal supersymmetry. We study the minima of the leading Wilson coefficient in D=6, 7 and 8 dimensions and find the global minimum at the point in moduli space with maximal symmetry. The minimum value turns out to always be negative for D<8.

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Guillaume Bossard, Adrien Loty. 2023-08-05. Saturating unitarity bounds at U-duality symmetric points. https://doi.org/10.1007/jhep10(2023)110

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