Causal Effective Field Theories

Abstract

Physical principles such as unitarity, causality, and locality can constrain the space of consistent effective field theories (EFTs) by imposing two-sided bounds on the allowed values of Wilson coefficients. In this paper, we consider the bounds that arise from the requirement of low-energy causality alone, without appealing to any assumptions about UV physics. We focus on shift-symmetric theories, and consider bounds that arise from the propagation around both a homogeneous and a spherically-symmetric background. We find that low-energy causality, namely the requirement that there are no resolvable time advances within the regime of validity of the EFT, produces two-sided bounds in agreement with compact positivity constraints previously obtained from $2\to 2$ scattering amplitude dispersion relations using full crossing symmetry.

38 pages, 5 figures (updated in v2)

References in corpus (11)

• Resummation of Massive Gravity
• Causality, Analyticity and an IR Obstruction to UV Completion
• Galileon inflation
• Eikonal phase matrix, deflection angle and time delay in effective field theories of gravity
• Riding on irrelevant operators
• Positivity Constraints for Pseudo-linear Massive Spin-2 and Vector Galileons
• Dispersion Relation Bounds for pi pi Scattering
• Causality Constraints on Black Holes beyond GR
• Causal vs. Analytic constraints on anomalous quartic gauge couplings
• A cautionary case of casual causality
• UV graviton scattering and positivity bounds from IR dispersion relations

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