Kepler motion on single-sheet hyperboloid
  The classical Kepler-Coulomb problem on the single-sheeted hyperboloid $H^{3}_1$ is solved in the framework of the Hamilton--Jacobi equation. We have proven that all the bounded orbits are closed and periodic. The paths are ellipses or circles for finite motion. 
Yu.A. Kurochkin, V.S. Otchik, L.G. Mardoyan, D.R. Petrosyan, G.S.   Pogosyan
math-ph math.MP