FROM ATOMS TO PLANETS AND STARS: WHAT CAN WE LEARN FROM AB INITIO SIMULATIONS?

François Soubiran – CEA DAM-DIF

The field of Research on compact objects ranging from planets to stars and neutron stars is very vivid with numerous dedicated observational campaigns. For instance, the transit detection method led to exquisite discoveries in the field of exoplanet, triggering some important paradigm shifts in our conception of planetary systems. But these observational data rely on the accurate determination of their stellar companions properties. In order to comprehend the structure, evolution and formation of the different compact objects it is crucial to understand the microphysics at play. With the advent of significantly improved computer capabilities and new numerical techniques, ab initio simulations proved to be an important asset in this area. They provide precise determinations of the physical properties of materials relevant for planets and stars on a wide range of thermodynamic conditions. In this presentation I will give a few examples of the capabilities of such simulations at the atomic scale. I will also explain how the microphysics can provide strong constraints on the global properties of stars and of planets, even on the habitability for the latter.