PhD defence, Monday 14 October 2019. Peter Skovlund Madsen.

2019.10.14 |

When a quantum mechanical system contains many particles, the full mathematical model of the system quickly becomes complicated and computationally heavy for computers to handle. For this reason, it is useful to have access to simpler models, which in an appropriate sense approximates the full model and exhibit many of the same characteristics.

During his studies, M.Sc. Peter Skovlund Madsen investigated a class of mathematical models describing large systems of so-called fermionic particles (think electrons), focusing on the cases where the systems is at positive temperature, or in the presence of a strong magnetic field. The models are very general and describe large atoms and molecules, among other things. In the dissertation, approximate models are derived, which in certain parameter regimes can be used to calculate ground state energies as well as particle densities of ground states.

The PhD degree was completed at the Department of Mathematics, Science and Technology, Aarhus University.

This résumé was prepared by the PhD student.

**Time:** Monday 14 October 2019 at 14.15

**Place:** Building 1531, room 215, Auditorium D3, Department of Mathematics, Aarhus University, Ny Munkegade 116, 8000 Aarhus C

**Title of PhD thesis:** *Semi-classical limits of large fermionic systems. A modern approach based on de Finetti theorems*

**Contact information:** Peter Skovlund Madsen, e-mail: psm@math.au.dk, tel.: +45 21674715

**Members of the assessment committee:**

Chargé de Recherche Nicolas Rougerie, French National Centre for Scientific Research, CNRS – LPMMC, Université Grenoble Alpes, France

Professor Daniel Ueltschi, Mathematics Institute, University of Warwick, United Kingdom

Associate Professor Erik Skibsted, Department of Mathematics, Aarhus University (chair)

**Main supervisor: **Professor Søren Fournais, Department of Mathematics, Aarhus University

The defence is public.

The PhD thesis is available for reading at the Graduate School of Science and Technology/GSST, Ny Munkegade 120, building 1521, 8000 Aarhus C.

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