Florian Beyer: Big bang dynamics of cosmological fluids

This talk concerns the existence and asymptotic behaviour of solutions to the relativistic Euler equations near big bang singularities. I will explain the context, with particular emphasis on the role of the equation of state in distinguishing different asymptotic regimes and on the potentially strong coupling between fluid tilt and anisotropies in the asymptotic geometry. I will conclude by discussing recent results for extremely tilted fluids on prescribed cosmological backgrounds.