3 October
Tuesday, September 30, 2025
Sunday, September 7, 2025
Autumn 2025
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From Wikipedia |
11, 18, 25 Sep 2025
Jerzy Kocik
Coxeter groups, and an unconventional view on the unimodular group (with pictures)
Part 1: Coxeter groups (the idea)
Part 2: Modular group as a Coxeter group
Part 3: "Supermodular" group and an unexpected application
For part 1, you may consult a nicely written text by J. Baez: Coxeter and Dynkin diagrams.
Tuesday, December 3, 2024
Wednesday, November 20, 2024
Saturday, November 2, 2024
Autumn 2024
7 and 14 Nov, Thursday
Jerzy Kocik
A certain expansion (evolvement) of ${\rm SL}(2,\mathbb Z)$ and its role as the symmetry group of the Apollonian "time crystal."
Tuesday, October 22, 2024
Autumn 2024
Wednesday, October 16, 2024
Autumn 2024
Jerzy Kocik
Wednesday, September 25, 2024
Autumn 2024
26 Sep, 3 Oct, and 10 Oct
K.V. ShajeshConjugate functions: A correspondence between analytic functions on a complex plane and electrostatic configurations in two dimensions
Part 3: Examples
Thursday, September 19, 2024
Wednesday, September 4, 2024
Autumn 2024
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From https://people.math.harvard.edu/~knill/pedagogy/pde/index.html |
5 Sep and 12 Sep
Mathew Gluck
How do researchers in PDEs think about PDEs
Abstract: The classical Poisson problem, say with homogeneous Dirichlet boundary data, seeks to determine which source functions are in the image of the Dirichlet Laplacian. In this talk I will briefly discuss the classical formulation of Poisson’s problem. I will then discuss the modern formulation (i.e., the weak formulation) of this problem in the case that the source is square integrable. Compared to the classical formulation, the modern formulation of Poisson’s problem requires a bit more up-front cost to understand. Specifically, one must (a) carefully specify both the domain and the codomain of the Laplacian and (b) completely overhaul how they understand the Laplacian. However, this extra up-front cost of understanding pays off. Indeed, the existence-uniqueness theory for the modern formulation of Poisson’s problem is much simpler than that for the classical formulation.
Students with interest in PDEs or related topics are especially encouraged to attend.