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Mateo Carmona (Nov 28 2021 at 19:13):As part of A Series of Trimester Programs on Triangle Groups, Belyi Uniformization, and Modularity (Youtube)
30th November 2021
Grothendieck's path from Topology to Arithmetic: Dessins d'enfants and the game of Lego-Teichmüller.
Speaker - Leila Schneps, CNRS France.
Time: Tuesday 16:00 Hrs IST (GMT +5:30).
Abstract: I will discuss Grothendieck-Teichmüller theory and introduce Grothendieck's original text, the Esquisse d'un Programme.
I will show how he envisaged to deepen the theory of dessins d'enfants into Grothendieck-Teichmüller theory.
Grothendieck was interested in surgery on topological surfaces and how this action translates into maps between moduli spaces of Riemann surfaces. These topological operations become not only geometric but even arithmetic, and give information about the absolute Galois group. This interplay between pure topology and arithmetic, fascinated Grothendieck. It would be a partly historical talk about the origins of these ideas.
Jens Hemelaer (Nov 29 2021 at 11:30):The talk will be livestreamed at this link: https://www.youtube.com/watch?v=2dcm_m-FDyE
It seems that the other talks in the trimester program are often livestreamed as well, the links are posted here on Twitter.
Mateo Carmona (Nov 29 2021 at 14:37):I was informed that "due to inevitable reasons we have postponed the talk".
I am going to be alert about the new date.
Mateo Carmona (Dec 15 2021 at 00:13):In case you missed it https://youtu.be/OQvOXCbcy8I