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arXiv · 1312.2021

Living with the Wrong Sign

Patrick Cooper·Sergei Dubovsky·Ali Mohsen
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Abstract

We describe a UV complete asymptotically fragile Lorentz-invariant theory exhibiting superluminal signal propagation. Its low energy effective action contains "wrong" sign higher dimensional operators. Nevertheless, the theory gives rise to an S-matrix, which is defined at all energies. As expected for a non-local theory, the corresponding scattering amplitudes are not exponentially bounded on the physical sheet, but otherwise are healthy. We study some of the physical consequences of this S-matrix.

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Patrick Cooper, Sergei Dubovsky, Ali Mohsen. 2013-12-06. Living with the Wrong Sign. https://doi.org/10.1103/physrevd.89.084044

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