Events tagged with Future students

Thursday, March 23, 2023 — 1:00 PM EDT

Title: Quasisymmetric varieties, excedances, and bases for the Temperley--Lieb algebra

Speaker: Lucas Gagnon
Affiliation: York University
Location: MC 6029 please contact Olya Mandelshtam for Zoom link

Abstract:  This talk is about finding a quasisymmetric variety (QSV): a subset of permutations which (i) is a basis for the Temperley--Lieb algebra TL_n(2), and (ii) has a vanishing ideal (as points in n-space) that behaves similarly to the ideal generated by quasisymmetric polynomials.   While this problem is primarily motivated by classical (co-)invariant theory and generalizations thereof, the course of our investigation uncovered a number of remarkable combinatorial properties related to our QSV, and I will survey these as well. 

Friday, March 24, 2023 — 3:30 PM EDT

Title: On the complexity of quantum partition functions

Speaker: David Gosset
Affiliation: University of Waterloo
Location: MC 5501 or contact Eva Lee for Zoom link

Abstract: Quantum complexity theory has been intertwined with the study of quantum many-body systems ever since Kitaev's insight that computing their ground energies is an intractable quantum constraint satisfaction problem that is complete for a quantum generalization of NP.

Monday, March 27, 2023 — 8:00 PM EDT

Title: Inverse eigenvalue problem of a graph

Speaker: Jephian C.-H. Lin
Affiliation: National Sun Yat-sen University
Location: Please contact Sabrina Lato for Zoom link

Abstract:  We often encounter matrices whose pattern (zero-nonzero, or sign) is known while the precise value of each entry is not clear. Thus, a natural question is what we can say about the spectral property of matrices of a given pattern. When the matrix is real and symmetric, one may use a simple graph to describe its off-diagonal nonzero support.

Wednesday, March 29, 2023 — 2:30 PM EDT

Title: Distance-Regular and Distance-Biregular Graphs

Speaker: Sabrina Lato
Affiliation: University of Waterloo
Location: MC

Abstract: For a given diameter d and valency k, what is the maximum number of vertices a k-regular graph of diameter d can have, and what graphs meet that bound? Although there is a straightforward counting argument to bound the number of vertices using the structural information, the problem of characterizing the graphs that meet the bound turns out to be a problem in algebraic graph theory, and helps gives rise to the notion of distance-regular graphs.

S M T W T F S
26
27
28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
1
  1. 2023 (34)
    1. March (16)
    2. February (10)
    3. January (8)
  2. 2022 (150)
    1. December (8)
    2. November (18)
    3. October (15)
    4. September (11)
    5. August (2)
    6. July (17)
    7. June (17)
    8. May (10)
    9. April (12)
    10. March (18)
    11. February (10)
    12. January (13)
  3. 2021 (103)
  4. 2020 (119)
  5. 2019 (167)
  6. 2018 (136)
  7. 2017 (103)
  8. 2016 (137)
  9. 2015 (136)
  10. 2014 (88)
  11. 2013 (48)
  12. 2012 (39)
  13. 2011 (36)
  14. 2010 (40)
  15. 2009 (40)
  16. 2008 (39)
  17. 2007 (15)