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arXiv · 1504.03027

Modified Gravity and Large Scale Flows

Jeremy Mould·Matthew Colless·Pirin Erdogdu·Heath Jones·John Lucey·Yin-Zhe Ma·Christina Magoulas·Christopher M Springob
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Abstract

Reconstruction of the local velocity field from the overdensity field and a gravitational acceleration that falls off from a point mass as r^-2 yields velocities in broad agreement with peculiar velocities measured with galaxy distance indicators. MONDian gravity does not. To quantify this, we introduce the velocity angular correlation function as a diagnostic of peculiar velocity field alignment and coherence as a function of scale. It is independent of the bias parameter of structure formation in the standard model of cosmology and the acceleration parameter of MOND. A modified gravity acceleration consistent with observed large scale structure would need to asymptote to zero at large distances more like r^-2, than r^-1.

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Jeremy Mould, Matthew Colless, Pirin Erdogdu, Heath Jones, John Lucey, Yin-Zhe Ma, Christina Magoulas, Christopher M Springob. 2015-04-12. Modified Gravity and Large Scale Flows. https://arxiv.org/abs/1504.03027

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