The atomic nucleus is often described as a chaotic quantum system, e.g. to model the nuclear reactions that are crucial for nucleosynthesis, i.e. the formation of the elements in the universe. By their very nature, models are simplifications of physical reality. One of our research focuses is to investigate under which conditions these simplifications are useful and when they are no longer applicable and therefore need to be adapted.

We have recently made significant progress in the study of fluctuations observed in the gamma decay of radioactive nuclei. Using a newly developed experimental method, we can now investigate whether the quantum states within an atomic nucleus are described as a chaotic system or rather by simpler nuclear structure models. Our initial results suggest that nature is more complex and that the answer may lie somewhere in between.