03/03/2016, 14:30 — 15:30 — Room P4.35, Mathematics Building
Geoffroy Horel, MPI, Bonn
The operad of little disks, differential topology and Galois theory
The operad of little $n$-disks is a fundamental object in algebraic topology that was introduced as a way of recognizing $n$-fold loop spaces. I will recall its definition and then survey some recent work of Dwyer–Hess and Boavida–Weiss relating mapping spaces between the operads of little disks and spaces of knots and higher dimensional knotted objects. I will then describe a faithful action of the absolute Galois group of $\mathbb{Q}$ on the profinite completion of the operad of little $2$-disks.
