Theoretical astrophysics in Oldenburg is primarily dedicated to the study of gravitation. This includes Albert Einstein's general theory of relativity, but also alternative theories of gravity. The field theory working group deals with theoretical models of astrophysical objects such as neutron stars, white dwarf stars and black holes. With the help of analytical and numerical methods, objects are also studied that were previously only predicted theoretically: Boson stars, wormholes and black objects in higher dimensions.