I’m interested in the formation of the large scale structure in our Universe using numerical simulations on cosmological scales.
After an early inflationary phase, our Universe is in a highly homogeneous state with tiny density perturbations. These density perturbations gravitationally collapse and form the structures that we can observe in our Universe today: from the temperature fluctuations measured in the Cosmic Microwave Background (CMB), to the filamentary structure of the cosmic web, individual galaxies and galaxy clusters, down to stars and planets.
Gravitational collapse is a non-linear process and requires numerical simulations to be accurately modelled. My work is mainly been in the context of large scale structure formation using numerical N-body simulations. In particular, I’m exploiting the Lagrangian mapping from coordinates in the initial condition to the late time positions and velocities to
- gain insight into the emergence of dark matter velocity dispersion (or stress) which allowed me to derive a new classification method of the cosmic web
- create a database of initial conditions for cosmological zoom-in simulations with a user friendly web front-end.
- Large Scale Velocity Dispersion and the Cosmic Web (M. Buehlmann, O. Hahn), MNRAS, Volume 487, Issue 1, July 2019, Pages 228–245, arXiv: 1812.07489