Seminary CEMPI

Our first meeting for the work group “Topologie et Matière”.

First talk

Speaker: Patrick Popescu-Pampu

Title : ‘Degrees, linking numbers, Euler characteristics and Chern numbers’

Abstract :

What do the degree of a polynomial, the linking number of two knots and the Euler characteristic of a surface have in common? All may be seen as Chern numbers of suitable complex line bundles over surfaces. This talk will be an introduction to this circle of ideas, in which by the way, topological games with circles will play a crucial role. As a preparation, one may read my outreach article about the Möbius band: http://images.math.cnrs.fr/La-bande-que-tout-le-monde-connait

Second talk

Speaker : Alberto  Amo

Title: Measurement of topological invariants in a photonic lattice

Abstract :

I will present the implementation of a Chern topological insulator in a synhtetic photonic lattice. Direct experimental access to the energy bands and eigenvectors allows us a direct measurement of the topological invariants of the system.