Precise Theory of Orbits in General Relativity with Cosmological Constant
Dr. Georgios Kraniotis
Texas A&M University

      The time-like geodesic equations resulting from the Kerr gravitational metric element are derived and solved exactly including the contribution from the cosmological constant. The geodesic equations are derived, by solving the Hamilton-Jacobi partial differential equation by separation of variables. The solutions can be applied in the investigation of the motion of a test particle in the Kerr and Kerr-(anti) de Sitter gravitational fields. In particular, we apply the exact solutions of the time-like geodesics i) to the precise calculation of dragging (Lense-Thirring effect) of a satellite's spherical polar orbit in the gravitational field of Earth assuming Kerr geometry, ii) assuming the galactic centre is a rotating black hole we calculate the precise dragging of a stellar polar orbit aroung the Galactic centre for various values of the Kerr parameter including those supported by recent observations. The exact solution of non-spherical geodesics in Kerr geometry is obtained by using the transformation theory of elliptic functions. The exact solution of the geodesics that derive from the Schwarzschild solution with a cosmological constant (i.e. non-rotating case) is applied to the precise calculation of the perihelion precession of the orbit of planet Mercury around the Sun.