Jeudi 1 juin 2017

The "Joint Seminar" is a research seminar in Arithmetic and Algebraic Geometry, organized by the research groups in Dijon, Freiburg, and Strasbourg. The seminar meets roughly once per semester in Strasbourg, for a full day.

There are about three talks per meeting, both by invited guests and by speakers from the organizing universities. We aim to leave ample room for discussions and for a friendly chat.

Organizers : Giuseppe Ancona (Strasbourg), Frédéric Déglise (Dijon) and Annette Huber (Freiburg)

The talks are open for everyone. Contact one of the organizers if you are interested in attending the meeting. We have some (very limited) funds that might help to support travel for some junior participants.

The seminar will meet in Strasbourg, June 1rst in the conference room of the institute (IRMA).

  • Jeudi 1 juin 2017

  • 09:30

    Localization of locally analytic admissible p-adic representation

    — Christine Huyghe (IRMA)

    (joint work with D. Patel, T. Schmidt, M. Strauch). Let G be a reductive group, Lie(G) its Lie algebra; X the flag variety of G. In the complex case, Beilinson-Bernstein and Brylinski-Kashiwara proved in the 80's that there is an equivalence of categories between the central representations of Lie(G) and the D-modules over the flag variety X. In this talk I will explain a p-adic analogous of this theorem. In this case G is a split reductive group, and representations we are considering are the central locally analytic representations of the Qp-points of the group G.
  • 10:30

    — Coffee Break

  • 11:00

    p-adic Hodge theory in motivic homotopy

    — Frédéric Déglise (Dijon)

    I will present a work in collaboration with Wiesia Niziol which aims to incorporate p-adic Hodge theory into the framework of modules over ring spectra, in the sense of Morel-Voevodsky's motivic homotopy theory. Our main result is the identification of "modules over syntomic cohomology" as a full subcategory of the derived category of potentially semi-stable representations, making use of ideas of Beilinson and Drew. I will then present an ongoing project to extend Fontaine semi-stable comparison to a suitable notion of syntomic modules. The later should be compared to Saito mixed Hodge modules, and our objective is to get some kind of p-adic Riemann-Hilbert correspondence.
  • 12:00

    If you wish to have lunch with us please send an email to ancona@math.unistra.fr by Monday 22nd May

    — Lunch

  • 14:30

    Tate Motives in Representation Theory

    — Wolfgang Soergel (Freiburg)

    A variant of the formalism of motivic sheaves, where the Tate objects do not extend among one another, can explain the phenomenon of graded versions of categories of representations underlying the character formulas of Kazhdan-Lusztig. This is joint work with Matthias Wendt.