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arXiv · 2012.04472

Weyl-Invariant Gravity and the Nature of Dark Matter

Meir Shimon
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Abstract

The apparent missing mass in galaxies and galaxy clusters, commonly viewed as evidence for dark matter, could possibly originate from gradients in the gravitational coupling parameter, $G$, and active gravitational mass, $M_{act}$, rather than hypothetical beyond-the-standard-model particles. We argue that in (the weak field limit of) a Weyl-invariant extension of General Relativity, one can simply affect the change $\Phi_{b}(x)\rightarrow\Phi_{b}(x) + \Phi_{DM}(x)$, where $\Phi_{b}$ is the baryon-sourced potential and $\Phi_{DM}$ is the `excess' potential. This is compensated by gradients of $GM_{act}$ and a fractional increase of $O(-4\Phi_{DM}(x))$ in the baryon density, well below current detection thresholds on all relevant scales.

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Meir Shimon. 2020-12-06. Weyl-Invariant Gravity and the Nature of Dark Matter. https://doi.org/10.1088/1361-6382%2Fabeae5

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