“Structure Formation and the Cosmic Web” with Oliver Hahn (University of Vienna, Austria)

A distinct prediction of our cosmological model is that tiny fluctuations seeded in the primordial Universe have grown under gravity to form the astrophysical objects we observe today. As a consequence of this formation process, on large scales, the matter in our Universe forms the cosmic web: an intricate network-like structure of filaments, sheets, nodes and large almost empty voids. This structure is at the interface between the ‘linear’ regime of cosmic structure formation and the deeply ‘nonlinear’ regime of galaxy formation. It thus fundamentally connects cosmology (and thereby fundamental physics) with the galaxy formation process. In this talk, we discuss how the cosmic web thereby plays a key role in our understanding of how galaxy formation connects to cosmic structure formation, how this connection can influence our interpretation of cosmological observables in the precision era, and how it can serve as a cosmological probe of the mildly non-linear scales. 

Oliver Hahn is a Professor for Data Science in Astrophysics and Cosmology at the University of Vienna (Austria) since 2020. He obtained his PhD in physics from ETH Zurich, Switzerland. He then worked as a postdoctoral researcher at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University (USA) from 2009-2012, before returning to ETH Zurich as an Ambizione postdoctoral fellow. In 2015, he joined the Université de la Côte d’Azur and the Observatoire de la Côte d’Azur (France) as a professor of Physics. Also in 2015 he received an ERC Starting Grant. His research interests center around the modelling of cosmic structures on supercomputers and range from the modelling of dark matter, galaxy clusters, to precision simulations of the large-scale structure, and include questions of numerical methods, data analysis, and high-performance computing.   

Webinar was recorded on October 20, 2022