Inconsistencies in Verlinde's emergent gravity

TL;DR

This paper critiques Verlinde's emergent gravity proposal, highlighting internal inconsistencies and demonstrating that it fails to produce MOND-like behavior, instead reverting to standard Newtonian gravity.

Contribution

It identifies fundamental issues in Verlinde's approach, questioning its viability as a modified gravity theory on large scales.

Findings

Gravity as an entropic force is problematic to justify.

The derivation of MOND from Verlinde's framework is inconsistent.

Proper analysis recovers Newtonian gravity, not MOND.

Abstract

We point out that recent Verlinde's proposal of emergent gravity suffers from some internal inconsistencies. The main idea in this proposal is to preserve general relativity at short scales where numerous tests verified its validity, but modify it on large scales where we meet puzzles raised by observations (in particular dark matter), by using some entropic concepts. We first point out that gravity as a conservative force is very difficult (if possible at all) to portray as an entropic force. We then show that the derivation of the MOND relation using the elastic strain idea is not self-consistent. When properly done, Verlinde's elaborate procedure recovers the standard Newtonian gravity instead of MOND.