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MOND mass-to-light ratios for galaxy groups

Mordehai Milgrom
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Abstract

I estimate MOND M/L values for nine galaxy groups that were recently studied by Tully et al.. Instead of the large M/L values that they find with Newtonian dynamics (up to 1200 solar units) the MOND estimates cluster around 1 solar unit. Tully et al. find a systematic and significant difference between the M/L values of groups that do not contain luminous galaxies and those that do: Dwarfs-only groups have larger M/L values (by a factor of about 5). The MOND M/L values do not show this trend; the Newtonian disparity is traced back to the dwarfs-only groups having systematically smaller intrinsic accelerations (similar sizes, but rather smaller velocity dispersions).

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Mordehai Milgrom. 2002-08-27. MOND mass-to-light ratios for galaxy groups. https://doi.org/10.1086/344253

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