Nonlocal metric formulations of MOND with sufficient lensing

TL;DR

This paper introduces nonlocal metric gravity models that replicate MOND behavior in ultra-weak fields, matching solar system tests and lensing data without dark matter, potentially arising from quantum effects.

Contribution

The authors develop nonlocal metric modifications of gravity that reproduce MOND phenomenology and lensing without dark matter, consistent with solar system constraints.

Findings

Models reproduce MOND force in ultra-weak fields

Models match gravitational lensing observations

Models agree with solar system tests

Abstract

We demonstrate how to construct purely metric modifications of gravity which agree with general relativity in the weak field regime appropriate to the solar system, but which possess an ultra-weak field regime when the gravitational acceleration becomes comparable to $a_0 \sim 10^{-10} {\rm m/s}^2$. In this ultra-weak field regime, the models reproduce the MOND force without dark matter and also give enough gravitational lensing to be consistent with existing data. Our models are nonlocal and might conceivably derive from quantum corrections to the effective field equations.