Cosmology in Delta-Gravity

TL;DR

This paper introduces a novel gravity model with two symmetric tensors that aligns with general relativity in classical tests but predicts accelerated cosmic expansion without dark energy and offers a new perspective on dark matter.

Contribution

The paper proposes a two-tensor gravity model that reproduces GR predictions locally while explaining cosmic acceleration and dark matter phenomena.

Findings

Model matches all classical tests of GR

Predicts accelerated expansion without dark energy

Provides a new approach to dark matter

Abstract

We present a model of the gravitational field based on two symmetric tensors. Gravity is affected by the new field, but outside matter the predictions of the model coincide exactly with general relativity, so all classical tests are satisfied. We find that massive particles do not follow a geodesic while massless particles trajectories are null geodesics of an effective metric. We study the Cosmological case, where we get an accelerated expansion of the universe without dark energy. We also introduce the possibility to explain dark matter with $\tilde{\delta}$ gravity.