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arXiv · 2208.12631

Positivity bounds in vector theories

Claudia de Rham·Laura Engelbrecht·Lavinia Heisenberg·Alice Lüscher
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Abstract

Assuming unitarity, locality, causality, and Lorentz invariance of the, otherwise unknown, UV completion, we derive a new set of constraints on the effective field theory coefficients for the most general, ghost-free Generalized Proca and Proca Nuevo massive vector models. For the Generalized Proca model, we include new interactions that had not been previously considered in the context of positivity bounds and find these additional terms lead to a widened parameter space for the previously considered interactions. Although, the Generalized Proca and Proca Nuevo models are inequivalent, we find interesting analogues between the coefficients parameterizing the two models and the roles they play in the positivity bounds.

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Claudia de Rham, Laura Engelbrecht, Lavinia Heisenberg, Alice Lüscher. 2022-08-26. Positivity bounds in vector theories. https://doi.org/10.1007/jhep12(2022)086

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