High Dimensional Expanders

Expander graphs, particularly Ramanujan graphs, have been a major focus of research over the last five decades. This research has yielded fruitful interactions between mathematics and computer science, with applications from one field benefiting the other. In recent years, a high dimensional theory of expanders has started to emerge.

In this lecture, Alexander Lubotzky will survey some of the achievements and challenges of this new theory. He will explain why this theory is not just a generalization but also an area that leads to new horizons in pure mathematics (such as topological overlapping) and computer science (such as property testing and locally testable codes).