Sharp boundaries for the swampland

@article{CaronHuot2021SharpBF,
  title={Sharp boundaries for the swampland},
  author={Simon Caron-Huot and Dalimil Maz{\'a}{\vc} and Leonardo Rastelli and David Simmons-Duffin},
  journal={Journal of High Energy Physics},
  year={2021}
}
Abstract We reconsider the problem of bounding higher derivative couplings in consistent weakly coupled gravitational theories, starting from general assumptions about analyticity and Regge growth of the S-matrix. Higher derivative couplings are expected to be of order one in the units of the UV cutoff. Our approach justifies this expectation and allows to prove precise bounds on the order one coefficients. Our main tool are dispersive sum rules for the S-matrix. We overcome the difficulties… 
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