Using Globular Clusters to Test Newtons Law of Gravity
نویسندگان
چکیده
New measurements of the velocity dispersion of the globular cluster ω Centauri allow to trace its gravitational potential down to an acceleration of 8 × 10 cm s. It is found that the dispersion profile remains flat well inside the tidal radius as soon as the acceleration of gravity approaches a0, a result that finds its simplest explanation within the contest of MOND. A similar behavior is observed in the globular cluster M15 showing this is not a peculiar features of ω Centauri. This result is surprising and suggestive of a failure of Newton’s law at low accelerations.
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