The mass of the graviton and the cosmological constant

TL;DR

This paper demonstrates that in a de Sitter background, the graviton naturally acquires a mass related to the cosmological constant, ensuring the gravitational field maintains its degrees of freedom.

Contribution

It provides a precise relation between the graviton mass and the cosmological constant in de Sitter space, highlighting a fine-tuning condition for gravitational perturbations.

Findings

Graviton mass in de Sitter space is given by m_g^2 = -2/3 Λ.

The graviton's degrees of freedom are preserved with this mass.

The result links the cosmological constant to the properties of gravitational waves.

Abstract

We show that the graviton acquires a mass in a de Sitter background given by $m_{g}^{2}=-{2/3}\Lambda.$ This is precisely the fine-tuning value required for the perturbed gravitational field to mantain its two degrees of freedom.