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arXiv · 2404.06375

Emergent Modified Gravity

Martin Bojowald·Erick I. Duque
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Abstract

A complete canonical formulation of general covariance makes it possible to construct new modified theories of gravity that are not of higher-curvature form, as shown here in a spherically symmetric setting. The usual uniqueness theorems are evaded by using a crucial and novel ingredient, allowing for fundamental fields of gravity distinct from an emergent space-time metric that provides a geometrical structure to all solutions. As specific examples, there are new expansion-shear couplings in cosmological models, a form of modified Newtonian dynamics (MOND) can appear in a space-time covariant theory without introducing extra fields, and related effects help to make effective models of canonical quantum gravity fully consistent with general covariance.

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Martin Bojowald, Erick I. Duque. 2024-04-09. Emergent Modified Gravity. https://doi.org/10.1088/1361-6382/ad36a8

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