Quartet unconstrained formulation for massive higher spin fields

TL;DR

This paper extends an unconstrained gauge-invariant formulation to describe free massive higher spin fields in flat space of any dimension, providing a local, simple, and minimal auxiliary field Lagrangian.

Contribution

It introduces a generalized unconstrained Lagrangian for massive higher spin fields applicable in arbitrary dimensions, simplifying previous formulations.

Findings

Lagrangian is local and free from higher derivatives

Uses minimal auxiliary fields for gauge invariance

Applicable to arbitrary spacetime dimensions

Abstract

We generalize the unconstrained description of free massless higher spin fields previously developed in [Nucl.Phys. B 779 (2007) 155] to the case of free massive higher spin fields in a flat space of arbitrary dimension. The Lagrangian is given in an easy-to-handle form for an arbitrary value of spin. It is local, free from higher derivative terms, and involves a minimal number of auxiliary fields needed for an unconstrained gauge invariant description of a free massive higher spin field in arbitrary dimension.