How an electron behaves in an atom, or how it moves in a solid, can be predicted precisely with the equations of quantum mechanics. These theoretical calculations agree fully with the results obtained from experiments. But complex quantum systems, which contain many electrons or elementary particles—such as molecules, solids or atomic nuclei—can currently not be described exactly, even with the most powerful computers available today. The underlying mathematical equations are too complex, and the computational requirements are too large. A team led by Professor Michael Bonitz from the Institute of Theoretical Physics and Astrophysics at Kiel University (CAU) has now succeeded in developing a simulation method, which enables quantum mechanical calculations up to around 10,000 times faster than previously possible. They have published their findings in the current issue of the renowned scientific journal Physical Review Letters.