Testing modifications of gravity

Dwarf galaxies test the proposal that the appearance of dark matter is due to a change in the law of gravity at low acceleations (<~ 10^-1^ cm s^-2^). The observed acceleration in bright galaxies eceeeds 25% of this value. We model six dwarf galaxies with low accelerations and show that Milgrom's non-Newtonian theory fails. Since these systems have large ratios of H I mass to luminosity (M_HI_/L), the non-Newtonian theory cannot be fitted by arbitarily lowering the mass-to-light ratio of the stellar component.