Martin Hairer (Fields Medal 2014) explains his current research on universality classes and how it links to the unsolved Millennium Problem on Yang-Mills and the Mass Gap Hypothesis.

Martin’s work looks at interfaces generated through random processes – which can be modelled using the video game Tetris. We begin by discussing ‘Ballistic Deposition’ which belongs to the ‘KPZ Universality Class’, before moving on to ‘Random Ballistic Deposition’ which gives rise to a completely new universality class which Martin names the ‘Brownian Castle’. Finally, Martin explains how his research in stochastic processes has led him to the Yang-Mills Mass Gap Hypothesis – one of 7 Millennium Problems that has a $1-million prize…

Part 1 on the original ‘Tetris Model’ is here.