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arXiv · 1211.5722

Modified entropic gravity revisited

Tower Wang
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Abstract

Inspired by Verlinde's idea, some modified versions of entropic gravity have appeared in the literature. Extending them in a unified formalism, we derive the generalized gravitational equations accordingly. From gravitational equations, the energy-momentum conservation law and cosmological equations are investigated. The covariant conservation law of energy-momentum tensor severely constrains viable modifications of entropic gravity. A discrepancy arises when two independent methods are applied to the homogeneous isotropic universe, posing a serious challenge to modified models of entropic gravity.

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Tower Wang. 2012-11-25. Modified entropic gravity revisited. https://arxiv.org/abs/1211.5722

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