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arXiv · 1803.08683

The Redshift-Dependence of Radial Acceleration: Modified Gravity versus Particle Dark Matter

Sabine Hossenfelder·Tobias Mistele
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Abstract

Modified Newtonian Dynamics has one free parameter and requires an interpolation function to recover the normal Newtonian limit. We here show that this interpolation function is unnecessary in a recently proposed covariant completion of Erik Verlinde's emergent gravity, and that Verlinde's approach moreover fixes the function's one free parameter. The so-derived correlation between the observed acceleration (inferred from rotation curves) and the gravitational acceleration due to merely the baryonic matter fits well with data. We then argue that the redshift-dependence of galactic rotation curves could offer a way to tell apart different versions of modified gravity from particle dark matter.

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Sabine Hossenfelder, Tobias Mistele. 2018-03-23. The Redshift-Dependence of Radial Acceleration: Modified Gravity versus Particle Dark Matter. https://doi.org/10.1142/s0218271818470107

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