Halos of Modified Gravity

TL;DR

This paper explores a modified gravity model where the local cosmological constant varies with curvature, predicting halos around objects that could explain dark matter effects in galaxies and are potentially observable with future experiments.

Contribution

It introduces a simple modification of general relativity allowing the local cosmological constant to depend on curvature, predicting observable halos around spherically symmetric objects.

Findings

Halos of modified gravity can surround spherical objects.

Mass of objects plus halos can be significantly larger than internal mass.

Local cosmological constant in the solar system could be much larger than cosmic value.

Abstract

We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space-time curvature, predicts the existence of halos of modified gravity surrounding spherically-symmetric objects. We show that the gravitational mass of an object weighed together with its halo can be much larger than its gravitational mass as seen from inside the halo. This effect could provide an alternative explanation of the dark-matter phenomenon in galaxies. In this case, the local cosmological constant in the solar system must be some six orders of magnitude larger than its cosmic value obtained in the supernovae type Ia experiments. This is well within the current experimental bounds, but may be directly observable in the future high-precision experiments.