New massive spin two model on curved space-time

TL;DR

This paper develops a new ghost-free massive spin two particle model on curved space-time by introducing specific non-minimal coupling terms, extending previous Minkowski space models to curved backgrounds.

Contribution

It constructs a ghost-free massive spin two model on curved space-time with novel non-minimal coupling terms, addressing previous issues with ghost instabilities.

Findings

The model remains ghost-free on curved space-time.

New non-minimal coupling terms are proposed.

The theory extends previous Minkowski space models.

Abstract

We have proposed a new ghost-free model with interactions of massive spin two particles in Phys.\ Rev.\ D {\bf 90} (2014) 043006 [arXiv:1402.5737 [hep-th]]. Although the model is ghost-free on the Minkowski space-time, it is not obvious whether or not this desirable property is preserved on curved space-time. In fact, Buchbinder et al. already pointed out that the Fierz-Pauli theory is not ghost-free on curved space-time without non-minimal coupling terms. In this paper, we construct a new theory of massive spin two particles with non-minimal coupling on curved space-time and show that the model can be ghost-free. Furthermore, we propose new non-minimal coupling terms.