Testing the Self-Consistency of MOND With Three-Dimensional Galaxy Kinematics

We propose a technique to test the idea that non-standard dynamics, rather than dark matter halos, might be responsible for the observed rotation curves of spiral galaxies. In the absence of non-luminous matter, a galactic disk's rotational velocity and its vertical velocity dispersion can be used jointly to test the self-consistency of the galaxy's dynamics. A specific illustrative example, using recent measurements of the disk kinematics of M33, shows this to be a promising approach to assess the viability of Modified Newtonian Dynamics (MOND).