## This week's discoveries: What is the shape of a knot?

A 15-minute lecture inviting the audience to understand knots by curving the space around it.

## 227 Seminar, Leiden

## Nationale Wiskunde Dagen 2015 and Nederlands Mathematisch Congres 2014

Lecture on the geometry of rotations, with many hands-on exercises (older English version).

## NSA symposium 2013

Lecture: a Random walk through number theory. About probabilistic heuristics in number theory.

## Vakantiecursus wiskunde 2013

I gave a series of lectures on G. Perelman's Ricci flow and his solution of the PoincarĂ© conjecture in the context of discrete surfaces.

## Dots & Boxes / Kamertjeverhuren

Together with Lisa Steverink and Marie-Beth van Egmond I organised the very first Dutch open Dots and Boxes championship at the University of Amsterdam.

## Lecture on quadratic reciprocity

I presented a pretty simple proof of the quadratic reciprocity law at the the Leve de wiskunde 2013 event. Here is the presentation and a short note containing the actual proof (Dutch). The actual lecture can be watched here (mine is the third presentation)

## Thesis defence dance performance

To convey the essence of my PhD thesis I gave a short dance demonstration.