Research group
Within the group we study various aspects of general relativity, such as the gravitational field inside and outside rotating stars, perturbation theory in cosmology and the coupling between gravity and matter in a kinetic description of matter.
For rotating stars we have, e.g., found that solutions describing the interior of the stars not always may be matched to external solutions for which the gravitational field vanishes at large distances. In cosmology we have used a coordinate invariant method to study the behavior of small disturbances, such as the propagation of gravitational waves and the growth of density fluctuations. Currently we are studying how matter and gravity mutually influence each other in a kinetic description of matter, given by the Boltzmann equation. Particle formation in cosmological models is also studied, using quantum kinetic theory.