The 1916 PhD Thesis of Johannes Droste and the Discovery of Gravitational Repulsion

One of the biggest mysteries of astrophysics is the question of how highly energetic particles in relativistic jets and cosmic rays are accelerated. Recently, it has been suggested that gravitational repulsion is the mechanism responsible for these phenomena. The little known concept of gravitational repulsion was first introduced by Johannes Droste in his Ph.D. thesis submitted to H.A. Lorentz in 1916. It was written in Dutch. We provide a translation.