Math Calendar

Friday, April 26, 2024
13:00-15:00
HFG 610
Friday Fish
Anna Nieuwenhuis – Holonomy from the algebroid point of view
In these talks we will first introduce holonomy groups, which arise from parallel transport on fibrations with a connection. We will state the classical Ambrose–Singer theorem, which states that the Lie algebra of these holonomy groups is generated by the curvature. Instead of proving this theorem in the classical way, we move to a Lie algebroid point of view. The connection induces a Lie algebroid that acts on the fibration. We then search for integrations of this Lie algebroid. By computing their isotropy groups, we can prove the classical Ambrose–Singer theorem, but we will have gained a lot more information along the way.
15:00-16:00
Minnaert 0.13
MSc presentation Anouk Eggink- Diophantine Maps

Supervisor: Gunther Cornelissen

Second reader: Valentijn Karemaker

 

Abstract:

My thesis is about Hilbert's tenth problemand Diophantine maps. Hilbert's tenth problem asks for an algorithm that givena polynomial equation with coefficients in the integer decides whether or notthis equation has a solution over the integers. In 1970 it has been proven thatsuch an algorithm does not exist. But mathematicians did not stop here, sincewe can easily generalize this problem: Does there exist an algorithm that,given a system of polynomial equations with coefficients in some ring R_0, decideswhether or not it has a solution in some ring R that contains R_0? The maintool that is used to get negative answers for various rings is to reduce theproblem to the integers. I have formalized this type of reduction viaDiophantine maps, which I will introduce in my talk. 

Then we will move to Hilbert's tenthproblem over some noncommutative rings. In my thesis I have proven severalresults about Hilbert's tenth problem over the twisted polynomial rings andvariants thereof. I also looked at differential polynomials and its divisionring of fractions. In my talk I will introduce some of these rings and some ofthe results I have proven.

I will assume knowledge of (polynomial)rings and fields and some knowledge of logic.

Monday, April 29, 2024
12:00-13:00
HFG 610
Freudenthal topology seminar
Lennart Meier - Atiyah's Real K-Theory

Atiyah's Real K-Theory is a C2-spectrum with fixed points KO and underlying spectrum KU. We present a modern-style construction of it and give streamlined proofs of its basic properties. 

Freudenthal topology seminar
Wednesday, May 1, 2024
13:00-14:00
BBG 161
AG seminar talk
Felix Wierstra - The Mumford conjecture
Abstract: The Mumford conjecture is an important result that computes the cohomology of the moduli space of curves in the stable range and was originally proved by Madsen and Weiss about 20 years ago. Recently, a new alternative proof of the Mumford conjecture was given by Bianchi. In this talk, I will discuss a version of Bianchi's proof which was further streamlined by Das and Petersen.
Thursday, May 2, 2024
16:00-17:00
HFG 611
Applied Math Seminar
János Flesch (Maastricht) for May 2, Equilibrium in stochastic games with Borel measurable evaluations
Tuesday, May 7, 2024
12:00-13:00
HFG 610
Freudenthal topology seminar
Maximilien Péroux - TBD
Tuesday, May 14, 2024
12:00-13:00
HFG 610
Freudenthal topology seminar
TBD - TBD
Wednesday, May 15, 2024
13:00-14:00
BBG 083
AG Seminar talk
Bianca Gouthier - tbd
Abstract: tbd
Thursday, May 16, 2024
16:00-17:00
HFG 611
Applied Math Seminar
Maosheng Yang (TU Delft)
Title: TBA
Abstract: TBA
Tuesday, May 21, 2024
10:00-11:00
KBG - ATLAS
AG Seminar talk
Rahul Pandharipande - Higher genus GW theory of the Hilbert scheme of points of the plane
Abstract: The quantum cohomology of the Hilb(C2,n) is determined by the operator of quantum multiplication by the divisor class (and was computed 20 years ago in work with Okounkov). I will explain how to think about the higher genus theory from several perspectives: CohFT, MNOP, and, in the case of genus 1, the intersection theory of the moduli space A_g of PPAVs. The talk is connected to recent joint and disjoint work of several mathematicians: S. Canning, F. Greer, A. Iribar Lopez, C. Lian, S. Molcho, D. Oprea, A. Pixton,and  H.-H. Tseng.
12:00-13:00
HFG 610
Freudenthal topology seminar
TBD - TBD
14:00-17:00
Ruppert Paars
Gongshow PhD UGC

TBD

Tuesday, May 28, 2024
12:00-13:00
HFG 610
Freudenthal topology seminar
TBD - TBD
16:00-17:00
HFG 611
UGC Seminar
Raymond Cheng (Hannover) - TBA
Wednesday, May 29, 2024
13:00-14:00
BBG 083
AG Seminar talk
Young-hoon Kiem - tbd
Abstract: tbd
Wednesday, June 5, 2024
13:00-14:00
BBG 083
AG Seminar talk
Thibault Poriet - tbd
Abstract: tbd
Thursday, June 6, 2024
16:00-17:00
HFG 611
Applied Math Seminar
Bernhard von Stengel (London School of Economics)
Friday, June 7, 2024
11:00-16:00
Mark Kac seminar in mathematical physics and probability
Yvan Velenik (U Geneva) and F. den Hollander (UL)
Wednesday, June 12, 2024
13:00-14:00
BBG 083
AG Seminar talk
Raju Krishnamoorthy - tbd
Abstract: tbd
Thursday, June 20, 2024
16:00-17:00
HFG 611
Applied Math Seminar
Gergely Bodo (UvA)
Wednesday, June 26, 2024
13:00-14:00
Minnaert 0.14
AG Seminar talk
Lucien Hennecart - tbd
Abstract: tbd
Thursday, June 27, 2024
16:00-17:00
HFG 611
Applied Math Seminar
Francesca Bartolucci (TU Delft)
Title : TBA
Abstract: TBA
Thursday, September 5, 2024
16:00-17:00
MI talk Yuri Kuznetsov
Title: Recent progress in the numerical bifurcation analysis of delay differential equations
Abstract: TBA