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arXiv · 2406.12959

Where is tree-level string theory?

Jan Albert·Waltraut Knop·Leonardo Rastelli
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Abstract

We investigate the space of consistent tree-level extensions of the maximal supergravities in ten dimensions. We parametrize theory space by the first few EFT coefficients and by the on-shell coupling of the lightest massive state, and impose on these data the constraints that follow from $2 \to 2$ supergraviton scattering. While Type II string theory lives strictly inside the allowed region, we uncover a novel extremal solution of the bootstrap problem, which appears to contain a single linear Regge trajectory, with the same slope as string theory. We repeat a similar analysis for supergluon scattering, where we find instead a continuous family of extremal solutionswith a single Regge trajectory of varying slope.

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Jan Albert, Waltraut Knop, Leonardo Rastelli. 2024-06-18. Where is tree-level string theory?. https://arxiv.org/abs/2406.12959

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