Organizers: Harry Tamvakis, Tom Haines, Jeffrey Adams
When: Mondays or Wednesdays @ 2pm
Where: Online for fall 2020
Pre-2012 Archives: Spring 2012 | Fall 2011 | Spring 2011 | Fall 2010 | Spring 2010 | Fall 2009 | Spring 2009 | Fall 2008

The seminar is being held via Zoom. Here is the zoom link. The password is the first six Fibonacci numbers (starting at 0).

Algebra Number Theory Seminar 

  • Robert Cass, September 14: A mod p geometric Satake isomorphisms
  • Sam Mundy, September 30:  An Arthur packet for real splilt G2
  • Dan Ciubotaru, October 5: An elliptic Fourier transform for unipotent representations of p-adic groups - (Note: the recording starts a few seconds late. The top lines of the slide say: Gamma is a finite group, (V,delta) is a representation, and v is in V)
  • Igor Rapinchuk, October 21: Algebraic groups with good reduction
  • Laura Rider, October 26: Modular perverse sheaves on the affine flag variety
  • XuhuaHe, November 11: Affine Deligne-Luztig varieties and generalized affine Springer fibers (slides)
  • Eugen Hellmann 1, November 16: On the Derived Category of the Iwahori-Hecke algebra 1 (slides)
  • Eugen Hellmann 2, November 18: On the Derived Category of the Iwahori-Hecke algebra 2 (slides)
  • Jessica Fintzen, November 23: Representations of p-adic groups (slides)
  • Jessica Fintzen , November 30: From representations of p-adic groups to congruences of automorphic forms
  • Lucas Mason-Brown, December 14: What is a unipotent representation? (slides)

Archives: 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021

  • A mod p geometric Satake isomorphism

    Speaker: Robert Cass (Harvard) - http://people.math.harvard.edu/~rcass/

    When: Mon, September 14, 2020 - 2:00pm
    Where: Zoom
  • An Arthur packet for real split G_2

    Speaker: Sam Mundy (Columbia University) - Abstract: In this talk we will have fun manipulating Arthur parameters for the exceptional group G_2. We will use these parameters to construct certain Arthur packets for G_2 via the work of Adams--Johnson. This is motivated by trying to understand cohomological properties of CAP representations for G_2.

    When: Wed, September 30, 2020 - 2:00pm
    Where: https://umd.zoom.us/j/96890967721
  • An elliptic Fourier transform for unipotent representations of p-adic groups

    Speaker: Dan Ciubotaru (Oxford) - Abstract: An important ingredient in the character theory of finite groups of Lie type is Lusztig's nonabelian Fourier transform which is the change of basis matrix between the basis of irreducible characters and the basis of "almost characters" (trace functions for character sheaves). The expectation is that a similar picture should exist for admissible representations of reductive p-adic groups, and in the case of representations with unipotent cuspidal support, Lusztig (2014) proposed several conjectures. Independently, Moeglin and Waldspurger defined an involution on the space of tempered unipotent representations of the odd orthogonal groups as part of their proof of the stability of tempered unipotent L-packets. Motivated by a more recent reformulation of this involution by Waldspurger (2017), we define a "nonabelian Fourier transform" on the space of elliptic representations of a semisimple p-adic group and verify, for split exceptional groups, that it commutes, via maximal parahoric restrictions, with Lusztig's Fourier transform for the finite reductive quotients.

    When: Mon, October 5, 2020 - 2:00pm
    Where: https://umd.zoom.us/j/96890967721
  • Algebraic groups with good reduction

    Speaker: Igor Rapinchuk (Michigan State University) - https://sites.google.com/site/irapinchuk1/home

    When: Wed, October 21, 2020 - 2:00pm
    Where: Zoom
  • TBA

    Speaker: Laura Rider (University of Georgia) - Modular Perverse Sheaves on the affine Flag Variety

    When: Mon, October 26, 2020 - 2:00pm
    Where: https://umd.zoom.us/j/96890967721
  • Affine Deligne-Lusztig varieties and Generalized affine Springer fibers

    Speaker: Xuhua He (CUHK) -

    When: Wed, November 11, 2020 - 8:00am
    Where: Online
  • On the derived category of the Iwahori-Hecke algebra, I

    Speaker: Eugen Hellmann (U. Münster) -

    When: Mon, November 16, 2020 - 2:00pm
    Where: Online
  • On the derived category of the Iwahori-Hecke algebra, II

    Speaker: Eugen Hellmann (U. Münster) -

    When: Wed, November 18, 2020 - 2:00pm
    Where: Online
  • Representations of p-adic groups

    Speaker: Jessica Fintzen (Cambridge U./Duke U.) -

    When: Mon, November 23, 2020 - 2:00pm
    Where: Online
  • From representations of p-adic groups to congruences of automorphic forms

    Speaker: Jessica Fintzen (Cambridge U. / Duke U.) -

    When: Mon, November 30, 2020 - 2:00pm
    Where: Online
  • A local Langlands conjecture for disconnected groups

    Speaker: Tasho Kaletha (U. Michigan) -

    When: Mon, December 7, 2020 - 2:00pm
    Where: Online
  • What is a unipotent representation?

    Speaker: Lucas Mason-Brown (Oxford University) -

    When: Mon, December 14, 2020 - 2:00pm
    Where: Online
  • TBA

    Speaker: Pol van Hoften (King's College London) -

    When: Mon, February 8, 2021 - 2:00pm
    Where: Online
  • TBA

    Speaker: Pol van Hoften (King's College London) -

    When: Wed, February 10, 2021 - 2:00pm
    Where: Online