Positivity bounds in vector theories

TL;DR

This paper derives new positivity bounds on effective field theory coefficients for ghost-free massive vector models, expanding the allowed parameter space and exploring analogies between different models under fundamental physical principles.

Contribution

It introduces novel positivity bounds for Generalized Proca models, including new interactions, and compares these bounds with Proca Nuevo, revealing interesting analogies.

Findings

New positivity bounds for Generalized Proca models.

Expanded parameter space due to additional interactions.

Analogies between Generalized Proca and Proca Nuevo coefficients.

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.