19/05/2026
Today (Wednesday) is Dies Academicus and we have two inaugural lectures in mathematics:
11:15, Lecture Room XII
Prof. Dr. Joshua Lam
Explain like I'm five: What is a differential equation?
In school, we all learn to solve equations: linear equations were ok, and there's a formula for quadratic equations. Somewhat later, we hear about differential equations: they come with strange symbols like d/dt, and teachers told us that they govern everyday physics, like how planets orbit, coffee cools, or stock markets crash, ..., but perhaps, just like for me, differential equations never really made sense to you the way usual equations did. In this talk, I will discuss how I overcame my fears of differential equations. I will give a brief, biased, and hopefully intuitive tour of the world of differential equations, including the works of Gauss, Riemann, Eisenstein, and Hilbert. I will try to highlight the appearance of these exotic equations in almost all branches of mathematics and science, including the study of tilings, dynamics, and even whole numbers.
14.15, Lecture Room XII
Prof. Dr. Tudor Padurariu
Curves and symmetries
In geometry, one starts by studying manifolds, spaces locally modeled by copies of the real or complex numbers. To understand a manifold of interest, such as a three-dimensional flat space or a four-dimensional curved shape, one approach is to classify special objects living on it, such as closed lines or spheres, alternatively, real or complex curves. Sometimes the collection of such objects is finite, and one is interested in counting them. Sometimes it is infinite, and the objects are parametrized by a new geometric space, called a moduli space, which is in itself a fascinating object.
Understanding the structure underlying these counts and these new spaces has been a driving problem across many areas of mathematics in recent decades, and continues to be so. In this talk, I will survey some aspects of these problems, focusing on the symmetries that these counts exhibit, related to infinite-dimensional Lie algebras and S-duality.