Using Globular Clusters to Test Newton?s Law of Gravityy

Riccardo Scarpa; Gianni Marconi; Roberto Gilmozzi

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Using Globular Clusters to Test Newton?s Law of Gravityy

Riccardo Scarpa·Gianni Marconi·Roberto Gilmozzi

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Abstract

New measurements of the velocity dispersion of the globular cluster omega Centauri allow to trace its gravitational potential down to an acceleration of 8e-9 cm/s/s. It is found that the dispersion profile remains flat well inside the tidal radius as soon as the acceleration of gravity approaches a_0, a result that finds its simplest explanation within the contest of Modified Newtonian dynamics. A similar behavior is observed in the globular cluster M15 showing this is not a peculiar features of omega Centauri. This result is surprising and suggestive of a failure of Newton's law at low accelerations.

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Riccardo Scarpa, Gianni Marconi, Roberto Gilmozzi. 2003-08-24. Using Globular Clusters to Test Newton?s Law of Gravityy. https://arxiv.org/abs/astro-ph/0308416

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