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arXiv · 1011.5741

The MOND Fundamental Plane

V. F. Cardone·G. Angus·A. Diaferio·C. Tortora·R. Molinaro
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Abstract

Modified Newtonian Dynamics (MOND) has been shown to be able to fit spiral galaxy rotation curves as well as giving a theoretical foundation for empirically determined scaling relations, such as the Tully - Fisher law, without the need for a dark matter halo. As a complementary analysis, one should investigate whether MOND can also reproduce the dynamics of early - type galaxies (ETGs) without dark matter. As a first step, we here show that MOND can indeed fit the observed central velocity dispersion $\sigma_0$ of a large sample of ETGs assuming a simple MOND interpolating functions and constant anisotropy. We also show that, under some assumptions on the luminosity dependence of the Sersic n parameter and the stellar M/L ratio, MOND predicts a fundamental plane for ETGs : a log - linear relation among the effective radius $R_{eff}$, $\sigma_0$ and the mean effective intensity $\langle I_e \rangle$. However, we predict a tilt between the observed and the MOND fundamental planes.

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V. F. Cardone, G. Angus, A. Diaferio, C. Tortora, R. Molinaro. 2010-11-26. The MOND Fundamental Plane. https://doi.org/10.1111/j.1365-2966.2010.18081.x

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