Gravitational Waves in New General Relativity

TL;DR

This paper analyzes the linearized vacuum equations of New General Relativity using cosmological perturbation theory to count degrees of freedom without complex Hamiltonian methods.

Contribution

It provides a straightforward method to determine the degrees of freedom in various versions of New General Relativity through linearized analysis.

Findings

Primary constraints are easily identified without Hamiltonian techniques.

Count of linearized degrees of freedom for each version of New General Relativity.

Clarifies the viability of models based on their degrees of freedom.

Abstract

The models of New General Relativity have recently got attention of research community, and there are some works studying their dynamical properties. The formal aspects of this investigation have been mostly restricted to the primary constraints in the Hamiltonian analysis. However, it is by far not enough for counting their degrees of freedom or judging whether they are any good and viable. In this paper we study linearised equations in vacuum around the trivial Minkowski tetrad. By taking the approach of cosmological perturbation theory we show that the numbers of primary constraints are very easily seen without any need of genuine Hamiltonian techniques, and give the full count of linearised degrees of freedom in the weak field limit of each and every version of New General Relativity without matter.