Lorentz covariant form of extended higher-spin equations

TL;DR

This paper reformulates extended higher-spin equations in four dimensions into a Lorentz covariant form, clarifying symmetry properties and fixing previously ambiguous terms, which simplifies perturbative analysis.

Contribution

The paper presents a Lorentz covariant reformulation of extended higher-spin equations, fixing central terms and simplifying perturbative calculations.

Findings

Lorentz covariance of extended higher-spin equations is established.

Ambiguous central terms are uniquely fixed by Lorentz symmetry.

Perturbative analysis is significantly simplified.

Abstract

The extension of nonlinear higher-spin equations in d=4 proposed in [arXiv:1504.07289] for the construction of invariant functional is shown to respect local Lorentz symmetry. The equations are rewritten in a manifestly Lorentz covariant form resulting from some Stueckelberg-like field transformation. We also show that the two field-independent central terms entering higher-spin equations which are not entirely fixed by the consistency alone get fixed unambiguously by the requirement of Lorentz symmetry. One of the important advantages of the proposed approach demonstrated in the paper is the remarkable simplification of the perturbative analysis.