Intrinsic Cutoff and Acausality for Massive Spin 2 Fields Coupled to Electromagnetism

TL;DR

This paper investigates the limitations of massive spin 2 fields coupled to electromagnetism, revealing an intrinsic cutoff linked to strong interactions and acausality, with implications for high-spin particle detection.

Contribution

It introduces a model-independent UV cutoff for massive spin 2 fields using the Stueckelberg formalism, connecting high-spin pathologies to fundamental theoretical constraints.

Findings

Identification of an intrinsic UV cutoff for the system

Link between cutoff and acausality in high-spin fields

Implications for high-spin particle detection

Abstract

We couple a massive spin 2 particle to electromagnetism. By introducing new, redundant degrees of freedom using the Stueckelberg formalism, we extract an intrinsic, model independent UV cutoff of the effective field theory describing this system. The cutoff signals both the onset of a strongly interacting dynamical regime and a finite size for the spin 2 particle. We show that the existence of a cutoff is strictly connected to other pathologies of interacting high-spin fields, such as the Velo-Zwanziger acausality. We also briefly comment on implications of this result for the detection of high spin states and on its possible generalization to arbitrary spin.