## Math Calendar

Tuesday, March 28, 2023

17:00-18:00

KBG Atlas

Thursday, March 30, 2023

17:00-18:00

MIN201

Friday, March 31, 2023

Wednesday, April 5, 2023

13:30-14:30

HFG-409

AG Seminar talk

Fabian Reede (Hannover) - Line bundles on noncommutative algebraic surfaces

see description

Abstract: Let X be a complex algebraic surface. Let A be a (noncommutative) coherent O_X-algebra whose generic stalk is a central division algebra. Then the pair (X,A) can be thought of as a noncommutative algebraic surface. This talk deals with the moduli space of line bundles on (X,A), i.e., of locally free A-modules of rank one, in the cases where X has Kodaira dimension zero or is Fano. It turns out that the moduli space can be compactified by adding torsion-free A-modules of rank one. We will study e.g. the smoothness of this compactification and the deformation theory of the sheaves involved. This is partly joint work with U. Stuhler and with N.Hoffmann.

AG seminar webpage: https://webspace.science.uu.nl/~marse004/ag_seminar.html

Thursday, April 13, 2023

Friday, April 14, 2023

11:00-16:30

Min 0.09

Mark Kac seminar in mathematical physics and probability -- Konstantin Khanin (U Toronto) and Vanessa Jacquier (UU)

see description

**Speaker 1**: Konstantin Khanin (U Toronto)

**Time**: 11-12.45

**Title**: The KPZ problem and Statistics of Stochastic Flows

**Abstract**: The KPZ (Kardar-Parisi-Zhang) problem is an extremely active research area which was actively studied in the last 15 years.

In this talk we will discuss a geometrical approach to the problem of the KPZ Universality.

Instead of looking at the height (interface) function and Airy processes, we will focus on the statistics of shocks and points of concentration of mass. We will also discuss the connection with the problem of the coalescing Brownian motions and coalescing fractional Brownian motions.

**Speaker 2**: Vanessa Jacquier (UU)

**Time**: 14.15-16.00

**Title**: Homogeneous and not homogeneous nucleation in the three–state Blume–Capel model

**Abstract**: We study the metastable behavior of the stochastic Blume–Capel model evolving according to the Glauber dynamics with zero boundary conditions. We will show that, due to the three–state character of the Blume–Capel model, the metastability scenario proven for periodic boundary condition changes deeply when different boundary conditions are considered.

The Hamiltonian of the Blume–Capel model depends on the magnetic field $h$ and the chemical potential $\lambda$. We study the heuristic in the whole region $\lambda,h > 0$, where the chemical potential term equally favors minus and plus spins with respect to zeroes and the magnetic field favors plusesand disadvantages minuses with respect to the zeroes, and we compere our results with the Blume-Capel model with periodic boundary conditions. Then, we analyze in detail the region $\lambda>h>0$. In this region, we identify the unique metastable state $\underline{-1}$, we compute the energy barrier from $\underline{-1}$ to the stable state $\underline{+1}$, and we find an estimate for the asymptotic behavior of the transition time from the metastable to the stable state as $\beta\to\infty$, where $\beta$ is the inverse of the temperature.

Tuesday, April 18, 2023

Wednesday, April 19, 2023

13:30-14:30

HFG-409

Thursday, April 20, 2023

11:00-13:00

Utrecht BBG077

Tuesday, April 25, 2023

Wednesday, May 3, 2023

13:30-14:30

HFG-409

AG Seminar talk

Chia-Fu Yu - Arithmetic invariants on supersingular Ekedahl-Oort (EO) strata for g=4

see description

Abstract: The supersingular locus is one of main interests in algebraic geometry in characteristic p, and can be described in terms of polarised flag type quotients (PFTQs) in the sense of Li and Oort. The description for g=3 is rather explicit and is exploited by Karemaker and Yobuko and myself for investigating the arithmetic invariants of supersingular abelian threefolds, namely, the endomorphism rings and automorphism groups of them, confirming Oort's conjecture for g=3. In this talk we shall explain a general method for investigating the arithmetic invariants on supersingular EO strata, and report the progress of the joint work with Karemaker for g=4.

AG seminar webpage: https://webspace.science.uu.nl/~marse004/ag_seminar.html

AG seminar webpage: https://webspace.science.uu.nl/~marse004/ag_seminar.html

Tuesday, May 9, 2023

15:30-17:30

Nijmegen

Wednesday, May 10, 2023

11:30-12:30

TBD

Tuesday, May 23, 2023

16:00-17:00

HFG-611

Thursday, May 25, 2023

11:00-13:00

Utrecht BBG077

Tuesday, June 20, 2023

Thursday, June 22, 2023

16:00-17:00

HFG 611

Tuesday, June 27, 2023

16:00-17:00

HFG 611