I am glad to share the slides of my recent talk at the ICBS Satellite Conference on Algebraic and Arithmetic Geometry, where I explained how Fraïssé theory and Galois theory can be extended and linked through a unified topos-theoretic framework that can possibly be applied to the problem of constructing motives and understanding the “independence of l” properties of l-adic cohomology.
Tag Archives: Unification
Videos of the Paris event of the Grothendieck Institute
The videos of the recent conference organized by the Grothendieck Institute at the Institut Henri Poincaré are now available from the Institute’s YouTube channel:
The event consisted in a round table with Alain Connes, Johanna Grothendieck and Laurent Lafforgue, moderated by Stéphane Dugowson and preceded by two brief presentations by Mateo Carmona, Coordinator of the Centre for Grothendieckian Studies, and myself.
Enjoy the videos!
Visit to China
From the 10th to the 26th of July I will be visiting the BIMSA, a world-class research institution established by the Chinese Ministry of Science and Technology and led by Prof. Shing-Tung Yau, to participate in the Inaugural International Congress of Basic Science (ICBS).
I will also give a plenary talk on the 12th at the ICBS Satellite Conference on Algebraic and Arithmetic Geometry on Toposic Galois-Fraïssé theory and motivic toposes; the abstract is as follows:
We will present an abstract topos-theoretic framework for building Galois-type theories in a variety of different mathematical contexts : this unifies and generalizes Grothendieck’s theory of “Galois categories” and Fraïssé’s construction of homogeneous structures in model theory. This theory notably allows one to construct fundamental groups in many classical contexts such as finite groups, finite graphs, motives and many more. We will in particular present an approach based on it for building “motivic toposes” and investigating the independence from l of l-adic cohomology.

Visions in mathematics: from Grothendieck to the present day
The Grothendieck Institute is hosting a conference for the general public on 14 June 2023 at the Institut Henri Poincaré in Paris. This meeting, entitled “Visions in mathematics: from Grothendieck to the present day“, will explore, with talks by Mateo Carmona, Alain Connes, Stéphane Dugowson, Johanna Grothendieck, Laurent Lafforgue and myself, the issues raised by the person and visionary work of A. Grothendieck from a philosophical, literary and sociological perspective. It will also discuss mathematical themes such as topos theory and its future in today’s mathematical landscape, industrial research and the dissemination of scientific knowledge.
The conference is free of charge and open to all upon prior registration on the Institute’s website.
Looking forward to seeing many of you there!

Talk at Logica Universalis Webinar
On Wednesday the 17th of May at 4 CET I will give a talk at the Logica Universalis Webinar on the contents of my paper “The unification of Mathematics via Topos Theory”, originally written in 2010 and recently published in the book “Logic in Question” (Studies in Universal Logic, Springer-Birkhäuser, 2022).
The talk will be accompanied by a short presentation of the Grothendieck Institute by Laurent Lafforgue.
Looking forward to seeing many of you there!
Video of Higher Structures Seminar talk
The video of my recent talk at the Higher Structures Seminar is now available:
Videos of the inaugural event of the Grothendieck Institute
The videos of the inauguration of the Grothedieck Institute, which took place on the 3rd of December in Mondovì, are now available from YouTube.
The event was held in Italian, with transations from French of Johanna Grothendieck and Laurent Lafforgue’ talks. Stil, automatic translated subtitles are available in all languages, through the relevant YouTube option.
Thanks again to all the speakers, and to the Municipality of Mondovì for the collaboration in the organization of this event!
Visit to Luxembourg
Tomorrow and on Friday I shall visit the University of Luxembourg, and give a talk on toposes as ‘bridges’ and their applications to artificial intelligence. More details about the talk can be found here.
Looking forward to it!
F1 World Seminar
Tomorrow, Wednesday the 22nd of March, at 14:30 CET, I shall give a talk on toposes as ‘bridges’ at the F1 World Seminar.
The talk can be attended through Zoom; to receive the link to connect, you have to subscribe to the seminar’s mailing list.
Further information is avaiable at the Seminar’s webpage.
Higher Structures Seminar
Tomorrow, Tuesday the 13th of March, I will give an online introductory talk to the theory of toposes as ‘bridges’ at the Higher Structures Seminar of the Feza Gursey Center for Physics and Mathematics at 16:45 (Istanbul local time) or 14:45 (CET).
You can attend the talk through Zoom, by clicking on this link and inserting the following credentials: Meeting ID: 969 5659 6842; Passcode: 442777.
Looking forward to seeing many of you there!