Diploma Thesis from the year 2011 in the subject Mathematics - Geometry, grade: 1,0, Humboldt-University of Berlin (Institut fur Mathematik), language: English, abstract: Based on the work of Adams and Stuck as well as on the work of Zeghib, we classify the Lie groups which can act isometrically and locally effectively on Lorentzian manifolds of finite volume. In the case that the corresponding Lie algebra contains a direct summand isomorphic to the two-dimensional special linear algebra or to a twisted Heisenbergalgebra, we also describe the geometric structure of the manifolds if they are...