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arXiv · 0901.3932

Can TeVeS avoid Dark Matter on galactic scales?

Nick E. Mavromatos·Mairi Sakellariadou·Muhammad Furqaan Yusaf
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Abstract

A fully relativistic analysis of gravitational lensing in TeVeS is presented. By estimating the lensing masses for a set of six lenses from the CASTLES database, and then comparing them to the stellar mass, the deficit between the two is obtained and analysed. Considering a parametrised range for the TeVeS function $mu(y)$, which controls the strength of the modification to gravity, it is found that on galactic scales TeVeS requires additional dark matter with the commonly used $mu(y)$. A soft dependence of the results on the cosmological framework and the TeVeS free parameters is discussed. For one particular form of $mu(y)$, TeVeS is found to require very little dark matter. This choice is however ruled out by rotation curve data. The inability to simultaneously fit lensing and rotation curves for a single form of $mu(y)$ is a challenge to a "no dark matter" TeVeS proposal.

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Nick E. Mavromatos, Mairi Sakellariadou, Muhammad Furqaan Yusaf. 2009-01-25. Can TeVeS avoid Dark Matter on galactic scales?. https://doi.org/10.1103/physrevd.79.081301

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