Unified Brane Gravity: Cosmological Dark Matter from Scale Dependent Newton Constant

TL;DR

This paper explores how unified brane gravity predicts a scale-dependent Newton constant, which could explain the nature of cosmological and galactic dark matter by modifying gravitational interactions.

Contribution

It introduces a unified brane gravity framework that maintains massless gravitons while allowing a variable Newton constant, offering a novel approach to dark matter phenomena.

Findings

Newton constant is lower in weak-field perturbations than in cosmology.

The model suggests a potential explanation for cosmological dark matter.

A conjecture links the modified gravity to galactic dark matter effects.

Abstract

We analyze, within the framework of unified brane gravity, the weak-field perturbations caused by the presence of matter on a 3-brane. Although deviating from the Randall-Sundrum approach, the masslessness of the graviton is still preserved. In particular, the four-dimensional Newton force law is recovered, but serendipitously, the corresponding Newton constant is shown to be necessarily lower than the one which governs FRW cosmology. This has the potential to puzzle out cosmological dark matter. A subsequent conjecture concerning galactic dark matter follows.