Title: Extreme scale N-body simulations and neutrino mass effects on the large scale structure of the Universe

Speaker: Hao-Ran Yu, Canadian Institute for Theoretical Astrophysics/Tsung-Dao Lee Institute

Time & Place: 周二, 2019.5.14下午2:30-4:30, 物理楼407

Abstract: Cosmological methods are promising in solving the neutrino mass problem. Accurately modelling nonlinear neutrino structures in the universe is extremely challenging. By using 86% of the then world’s fastest supercomputer Tianhe-2, our simulation TianNu breaks the world record by executing a 3-trillion-particle N-body simulation, and it discovers a number of new neutrino mass effects on the large scale structure of the universe. I will discuss our developments in N-body methods for these extreme scale simulations, and briefly two of the neutrino effects — “differential neutrino condensation” and “neutrino tidal torque”. In the second part of the talk I will expand the neutrino torque effect to the framework of “spin cosmology”, which focuses on the angular momentum alignment of dark matter halos and galaxies with large scale structure. The spin field in principle contains comparable amount of cosmic information as the density field and brings independent ways in understanding the gravitational dynamics of large scale structure.