Massive graviton as a testable cold dark matter candidate

TL;DR

This paper proposes a gravity model with a massive tensor graviton that could serve as cold dark matter, potentially detectable through future gravitational wave experiments, and consistent with current pulsar timing constraints.

Contribution

It introduces a consistent gravity model with a massive graviton as a cold dark matter candidate, linking modified gravity to dark matter phenomenology.

Findings

Graviton mass constrained by pulsar timing to about (10^{15} cm)^{-1}

Non-relativistic gravitational waves could form cold dark matter

Model predicts accelerated expansion due to dark energy component

Abstract

We construct a consistent model of gravity where the tensor graviton mode is massive, while linearized equations for scalar and vector metric perturbations are not modified. The Friedmann equation acquires an extra dark-energy component leading to accelerated expansion. The mass of the graviton can be as large as $\sim (10^{15}{cm})^{-1}$, being constrained by the pulsar timing measurements. We argue that non-relativistic gravitational waves can comprise the cold dark matter and may be detected by the future gravitational wave searches.