Galaxy rotation curves in superfluid vacuum theory

Logarithmic superfluid theory of physical vacuum suggests that gravity has a multiple-scale structure, where one can recognise sub-Newtonian, Newtonian, logarithmic, linear and quadratic (de Sitter) terms in the induced space-time metric and effective potential. To test the theory's predictions on a galactic scale, we apply best-fitting procedures to the rotation curve data obtained from 15 galaxies by the HI Nearby Galaxy Survey, assuming their stellar disk's parameters to be fixed to the mean values measured using photometric methods. Although the fitting results seem to be sensitive to the stellar disk model chosen, they correspond closely with the observational data, even for those galaxies for which the rotation velocity profiles do not have flat regions.