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تسجيل مستخدم جديدUsing globular clusters to test gravity in the weak acceleration regime
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We report on the results from an ongoing program aimed at testing Newtons law of gravity in the low acceleration regime using globular clusters. It is shown that all clusters studied so far do behave like galaxies, that is, their velocity dispersion profile flattens out at large radii where the acceleration of gravity goes below 1e-8 cm/s/s, instead of following the expected Keplerian fall off. In galaxies this behavior is ascribed to the existence of a dark matter halo. Globular clusters, however, do not contain dark matter, hence this result might indicate that our present understanding of gravity in the weak regime of accelerations is incomplete and somehow incorrect.
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A test of Newtons law of gravity in the low acceleration regime using globular clusters is presented. New results for the core collapsed globular cluster NGC 7099 are given. The run of the gravitational potential as a function of distance is probed s
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Non-baryonic Dark Matter (DM) appears in galaxies and other cosmic structures when and only when the acceleration of gravity, as computed considering only baryons, goes below a well defined value a0=1.2e-8 cm/s/s. This might indicate a breakdown of N
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Stellar kinematics in the external regions of globular clusters can be used to probe the validity of Newtons law in the low acceleration regimes without the complication of non-baryonic dark matter. Indeed, in contrast with what happens when studying
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