Spherically symmetric steady states of galactic dynamics in scalar gravity

The kinetic motion of the stars of a galaxy is considered within the framework of a relativistic scalar theory of gravitation. This model, even though unphysical, may represent a good laboratory to study in a rigorous, mathematical way those problems, such as the influence of the gravitational radiation on the dynamics, which are still beyond our present understanding of the physical model represented by the Einstein-Vlasov system. The present paper is devoted to deriving the equations of the model and to proving the existence of spherically symmetric equilibria with finite radius