Many celestial bodies such as stars or planets contain matter that is exposed to high temperatures and pressure - experts refer to this as warm dense matter (WDM). Although this condition on Earth only occurs in the Earth's core, research into WDM creates fundamental prerequisites for numerous future areas such as clean energy, harder materials or a better understanding of our solar system. A team led by the Center for Advanced Systems Understanding (CASUS) at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has now shown that warm dense matter behaves significantly differently than assumed, which calls into question its previous description.
In order to be able to research the exotic state of warm dense matter on Earth, it is artificially created in the laboratory. This is achieved, among other things, by compression using powerful lasers. However, important parameters such as temperature or density cannot be measured directly. Theoretical models are therefore of central importance for the evaluation of WDM experiments. Such simulation models for the theoretical description of warm dense matter are being developed. Contrary to the expectation that the samples react more strongly the more they are "disturbed" by the laser radiation (linear reactions), these models show the opposite result: contrary to this assumption, the system reacts significantly weaker the stronger the disturbance (non-linear reactions). These results have far-reaching implications for the interpretation of experiments with warm dense matter.
Research into warm dense matter is not only important for understanding the structure of planets such as Jupiter and Saturn or our solar system and its development, but is also used in materials science, for example in the development of super-hard materials. However, it could play the most important role for the energy industry by contributing to the realization of inertial confinement fusion, an almost inexhaustible and clean energy source with future potential.
