The spectrum of teleparallel gravity

TL;DR

This paper explores the broad spectrum of teleparallel gravity, generalizing existing models with new functions and clarifying degrees of freedom, potentially leading to UV-complete theories and new gravitational wave polarizations.

Contribution

It introduces a general covariant quadratic form for the frame field in arbitrary dimensions, extending New General Relativity with nine functions of the d'Alembertian operator.

Findings

Clarification of degrees of freedom via covariant propagator derivation

Models can incorporate UV completion of gravity

Potential for additional gravitational wave polarizations

Abstract

The observer's frame is the more elementary description of the gravitational field than the metric. The most general covariant, even-parity quadratic form for the frame field in arbitrary dimension generalises the New General Relativity by nine functions of the d'Alembertian operator. The degrees of freedom are clarified by a covariant derivation of the propagator. The consistent and viable models can incorporate an ultra-violet completion of the gravity theory, an additional polarisation of the gravitational wave, and the dynamics of a magnetic scalar potential.