Vic Reiner- talks

• q-Ehrhart theory
  • Ehrhart theory and a q-analogue, Texas A&M Colloquium, April 11, 2025.
    
  • Ehrhart theory and a q-analogue, DePaul Colloquium, March 14, 2025.
    
  • Ehrhart theory and a q-analogue, UIUC Colloquium, September 19, 2024.
    
  • Ehrhart theory and a q-analogue, UMN Combinatorics Seminar, September 13, 2024.
    
  • Macaulay inverse systems and graded Ehrhart theory, Uwe Nagel 60th Birthday Fest, Notre Dame, August 12, 2024.
    
  • PechaKucha 6-slide/6-minute talk, Richard Stanley 80th Birthday Fest, Harvard University, June 4, 2024.
    
  • A q-analogue of Ehrhart theory, U. Minn. CAAG seminar chalk talk, Feb. 11, 2025.
• Descents, peaks and configuration spaces, video
  ICECA (International Conference on Enumerative Combinatorics and Applications- virtual), August 27, 2024.
  
• Combinatorics of configuration spaces: recent progress
  University of Rome- Tor Vergata Colloquium, November 3, 2023.
  
• Franceso, Polya frequency sequences, and Koszulity
  89th Seminaire Lotharingien de Combinatoire, BrentiFest, Bertinoro, March 28, 2023.
  
• Stirling representations, Koszulity, supersolvability, etc
  • Koszulity and Stirling representations Various Guise of Reflection Groups, ICMS Edinburgh, March 14,2023.
  • Stirling numbers, Koszulity, representations and supersolvability Seminaire Combinatoire et Theorie de Nombres, ICJ Lyon, October 3, 2023.
  • Stirling numbers and Koszul algebras with symmetry Symmetry, stability and interactions with computation, CIRM-Luminy, November 14,2023.
  • Stirling numbers and Koszul algebras with symmetry Seminaire Groupes, Algebre et Topologie, Univ. de Picardie-Jules Verne, Amiens, December 7, 2023.
  • Stirling numbers and Koszul algebras with symmetry Workshop on Geometric, Algebraic and Topological Combinatorics, Oberwolfach, December 11, 2023.
  • Koszulity and Stirling representations CombinaTexas, Texas A&M, April 13, 2025.
• Left-regular bands
  • Hop on the left-regular band-wagon!
    Michigan State Math Colloquium, October 27, 2022.
    
  • Invariant theory for the free left-regular band and a q-analogue
    Sectional AMS meeting at U. Mass-Amherst, October 1-2, 2022.
    
• Hooked on the work of Adin and Roichman
  Reflections: 60th birthday of Ron Adin and Yuval Roichman,
  satellite to FPSAC 2021, Bar Ilan University, Jan 10, 2022
  
• Topology of augmented Bergman complexes,
  • talk at CALICO, Univ. Oregon, Nov. 6, 2021
  • talk in Copenhagen-Jerusalem Combinatorics Seminar, Nov. 17, 2021
  • talk in AMS Southeastern Sectional Virtual Alabama, Nov. 20, 2021
  • talk in Brown Combinatorics Seminar, Apr. 19, 2022
• Invariant theory of cyclic permutations: a test case
  CA+ Conference, Minneapolis, October 30, 2021
  
• Conjecture on cohomology of Grassmannians
  Michigan State Combinatorics and Graph Theory Seminar, April 21, 2021
  
• Colorful Hochster formula and universal parameters
  • Universal parameters for Stanley-Reisner rings and a colorful Hochster formula
    (Polytop)ics, MPI-Leipzig, April 9, 2021
    
  • Resolutions of Stanley-Reisner rings and a colorful Hochster formula
    Univ. of Minnesota Commutative Algebra Seminar, May 20,2020
    (and here is a talk by Ashleigh Adams on this topic at GSCC 2021 a few weeks later)
• q-Binomials and the Grassmannian
  Polymath Jr REU 2020 problem intro talk; here is a video recording.
• Whitney numbers for poset cones
  • Whitney numbers for poset cones
    Mittag-Leffler ACOW (Algebraic Combinatorics Online Workshop, April 30,2020
    
  • Whitney numbers for poset cones
    AMS Southeastern Sectional in Gainesville FL
    Special Session on Geometric and Topological Combinatorics, Nov. 3, 2019
• Coincidental reflection groups
  • Combinatorics of the coincidental reflection groups
    FPSAC in Ljubljana, Slovenia, July 5, 2019
  • On the coincidental reflection groups
    Arrangements at Western, U. Western Ontario, May 21, 2019
  • On the coincidental reflection groups
    MAAGC, Drexel Univ., May 4, 2019
  • On invariant theory for "coincidental" reflection groups
    U. Minnesota Commutative Algebra seminar, Nov. 29, 2018.
    
• Finite reflection groups and general linear groups
  A Pan-Hemispheric Celebration of Math in Miami (ICM satellite), July 26, 2018
• Sandpiles and representation theory
  • Sandpiles and Representation Theory
    Univ. of Waterloo Algebraic and Enumerative Combinatorics Seminar, June 18, 2020.
  • Sandpiles and representation theory
    Maheshwari Colloquium at SUNY-Albany, May 4, 2018
  • Sandpiles and representation theory
    Cornell Math Colloquium (Oliver Club), Mar. 14, 2018
  • Sandpiles and representation theory
    The George Washington Univ. Colloquium, Feb. 23, 2018
  • Sandpiles and Hopf algebras
    ThibonFest, Séminaire Lotharingien de Combinatoire 78,
    Domaine St. Jacques, Ottrott, March 27, 2017
  • Sandpiles for group representations
    Great Plains Combinatorics Conference, Univ. of Kansas, May 20, 2016
• Hilbert functions for Chow rings of uniform matroids and their q-analogues
  Joint Math. Meetings, San Diego CA, Jan. 12, 2018.
• Thrall's problem and coarsenings
  Positivity in algebraic combinatorics, BIRS, August 15, 2015.
• Cyclic symmetry
  Smith College Thursday Lunch Talks, April 9, 2015.
• Representation stability
  • Sharp representation stability for configurations of points in R^d
    Loyola Univ. AMS Central Sectional Mtg., Oct. 3-4, 2015.
  • Sharp representation stability for configurations of points in R^d
    Univ. Arkansas Spring Lecture Series, March 5-7, 2015.
• q-Narayana and q-Kreweras numbers for Weyl groups
  From WachsFest, Univ. of Miami - Coral Gables, January 5-9, 2015.
• Catalan numbers,parking functions, and invariant theory
  From CanaDAM, St. Johns, Newoundland June 10-13, 2013.
• Toric partial orders
  From AMS meeting in Boulder, Colorado, April 13-14, 2013.
• Parking spaces
  From AMS meeting in Oxford, Mississippi, March 1-3, 2013.
• New twisted Gelfand pairs from reflection groups
  From "q-Series 2011: a conference honoring M. Ismail and D. Stanton"
  at Georgia Southern University, March 14-16, 2011
• P-partitions revisited
  From "Combinatorial algebra meets algebraic combinatorics"
  conference at Lakehead Univ. in Thunder Bay, January 21-23, 2011
  and Triangle Lectures in Combinatorics at NC State, March 9, 2011
• Cyclic symmetry, invariant theory, and q- and t-analogues
  (from Seminaire Lotharingien de Combinatoire, Heilsbronn, Feb. 2009)
• Face numbers of nestohedra
  (from Minisymposium Algebraische und geometrische Kombinatorik, Erlangen, Sept. 2008)
• Two talks from the AMS Winter meeting New Orlean, Jan 2007
  • Invited address: New combinatorics from the invariant theory of reflection groups
  • Special session: A generalization of the Chevalley-Mitchell theorem,
• Koszul algebras in combinatorics
  (from MSRI workshop March 2003)
• Recent progress in the topology of simplicial complexes
  (from AMS meeting in Williamstown MA, Oct. 2001)
• The Geology of Gale diagrams, extra scanned slides

• Counting and cyclic symmetry
  Sue Geller Undergraduate Lecture, Texas A&M, April 10, 2025.
  
• Counting and cyclic symmetry
  SUMS (Shenandoah Undergrad Math and Stats Conference), James Madison Univ., Nov 2, 2024.
  
• The Koszul property in algebraic combinatorics
  MPI-Leipzig Summer School in Algebraic Combinatorics
  Leipzig, Germany July 15-19, 2024
  
• q-counting and invariant theory
  Summer School in Algebraic Combinatorics
  Kraków, Poland, July 11-15, 2022
  
  • Reference: Reflection groups and enumeration, with A. Morales and N. Villamizar),
  • Slides for lecture 1, lecture 2, lecture 3, lecture 4, lecture 5.
• Cyclic and dihedral sieving
  Texas State University REU talk, July 22, 2021
• Hurwitz's factorization count and its deformations
  Helen Barton Lecture, UNC-Greensboro (via Zoom), Aug. 26, 2020.
  
• Counting trees and nilpotent endomorphisms
  U. Minnesota Combinatorics seminar (via Zoom), Mar. 27, 2020.
  
• Cyclic sieving: old and new
  Northeast Combinatorics Network's Virtual Combinatorics Colloquium, Nov. 14, 2018
  
• q-counting and representation theory
  ECCO (Encuentro Colombiano de Combinatoria) 2018 Summer School
  Barranquilla, Colombia, June 5-9, 2018
  
  • Reflection groups and enumeration,
    (with A. Morales and N. Villamizar),
    chapter in a forthcoming book of ECCO lectures by Camb. Univ. Press
  • Lecture 1 slides, exercises
  • Lecture 2 slides, exercises
  • Lecture 3 slides, exercises
  • Lecture 4 slides, exercises
• Reflection group invariant theory and generatingfunctionology
  Algebraic and Geometric Combinatorics of Reflection Groups
  Spring School, CRM-LaCIM-UQAM, Montreal, June 1-2, 2017
  • Talk part 1,
  • Talk part 2,
  • Exercise sheet
  • SAGE tutorial on reflection groups by N. Thiery
• General linear groups as reflection group 'wannabes'
  video
  • Talk 2: Catalan numbers PDF slides
  • Talk 3: reflection factorizations PDF slides
  Aisenstadt Lectures at CRM, Univ. de Montreal, March 14-17, 2017
• General linear groups as reflection group 'wannabes'
  Algebraic combinatorics and group actions, Herstmonceux Castle, UK, July 12, 2016
  
• Cyclic symmetry? You can count on it!
  Fisk Lecture, Univ. of Wyoming, March 31, 2016
  
• Reflection groups and finite general linear groups
  from a mini-course at Centro di Recerca Matematica Ennio De Giorgi, Pisa, Feb. 9-13, 2015
  during the INdAM intensive research period "Perspectives in Lie Theory"
• The Art Gallery Theorem
  UW Monthly Math Hour, May 18, 2014
  The Art Gallery Theorem
  St. John's Univ., Collegeville MN, Sept. 15, 2015, and Augsburg College, Minneapolis MN, March 9, 2016.
• Rational Catalan Combinatorics: Intro
  from AIM meeting Dec. 17-21, 2012
• Lectures on reflection group counting and q-counting
  from Algebraic and Enumerative Combinatorics Summer School in Guimaraes, Portugal, July 2012
• Algebraic combinatorics: using algebra to help one count
  Max and Rose Lorie Lecture #1, George Mason Univ., Jan 29, 2010.
  Its precursor talk
  given as a Minnesota Jr. Colloquium on Jan 24, 2006
• Lectures on matroids and oriented matroids
  from ACE Geometric Combinatorics Summer School, Univ. Vienna, 2005

• Hall-Littlewood polynomials
  U. Minn. Grad Combinatorics Seminar, Oct. 22, 2015.
• Intro to McKay correspondence
  An informal seminar in Winter 2016 at U. Minn., with 3 talks by me on Feb. 1,8,15, then one by Theo Douvropoulos on Feb. 22.
  A seminar resource list is here.
• Hodge theory and matroids
  U. Minn. Grad Combinatorics Seminar, Oct. 20 and Nov. 17, 2016.
• Topology and combinatorics of the complex of injective words
  U. Minn. Algebraic Representation Theory Seminar, Oct. 26 and Nov. 2, 2018.
• Seminar on Kraskiewicz-Weyman 1985, and video
  A mini-seminar at Minnesota, Mar. 16, 2021.
  
• Some talks on B. Steinberg's book "Representation Theory of Finite Monoids"
  U. Minn. Algebra Reading Seminar on Semigroups
  • Sept. 28 and Oct. 4, 2021
  • Apr. 12, 19, 2022
• Notes from subbing for Gregg Musiker's Math 8680 in November 2024
  • Nov 11 on McKay correspondence
  • Nov 13 on cyclic sieving phenomena
• Note from subbing for Anna Weigandt's Math 8680
  Feb 19, 2025 on Hochster and dual Hochster formulas for resolutions of Stanley-Reisner rings.

• A glimpse of Minnesota combinatorics, March 26, 2011
• A glimpse of Minnesota combinatorics, March 23, 2018
• A glimpse of Minnesota combinatorics, March 30, 2019

• 7-minute movie from April 2020,