Bienvenue sur le site du laboratoire J.-L. Lagrange
Alisson Pellissier-Michel Boulevard de l’Observatoire CS 34229 06304 Nice Cedex 4 France
Galaxies in our Universe are not randomly distributed, but rather follow the filamentary structure of the cosmic web. Filaments intersect in nodes which host hundreds to thousands of galaxies that are gravitationally bound to each other forming so called galaxy clusters. These clusters of galaxies occupy a special position in the Universe’s hierarchy : they are the most massive and the largest objects that have had time to undergo gravitational collapse. They constitute powerful cosmological probes, and from their properties we can learn a lot about the physical processes governing the evolution of our Universe.
In this context, I am particularly interested in the evolution of galaxy clusters and understanding how are they are shaped by different physical processes such as turbulence, magnetic fields and relativistic cosmic rays. For this purpose, I am performing multi-physics hydrodynamical simulations of galaxy clusters in a cosmological environment using the RAMSES code.
Master’s degree in astrophysics, Universtity of Côte d’Azur, Nice
Bachelor’s degree in physics, University of Aix-Marseille, Marseille
Michael Buehlmann Boulevard de l’Observatoire CS 34229 06304 Nice Cedex 4 France
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