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arXiv · 0802.1122

Dynamical friction in modified Newtonian dynamics

C. Nipoti·L. Ciotti·J. Binney·P. Londrillo
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Abstract

We have tested a previous analytical estimate of the dynamical friction timescale in Modified Newtonian Dynamics (MOND) with fully non-linear N-body simulations. The simulations confirm that the dynamical friction timescale is significantly shorter in MOND than in equivalent Newtonian systems, i.e. systems with the same phase-space distribution of baryons and additional dark matter. An apparent conflict between this result and the long timescales determined for bars to slow and mergers to be completed in previous N-body simulations of MOND systems is explained. The confirmation of the short dynamical-friction timescale in MOND underlines the challenge that the Fornax dwarf spheroidal poses to the viability of MOND.

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C. Nipoti, L. Ciotti, J. Binney, P. Londrillo. 2008-03-31. Dynamical friction in modified Newtonian dynamics. https://doi.org/10.1111/j.1365-2966.2008.13192.x

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