Math Calendar

Friday, November 24, 2017
11:00-12:00
BBG 106
Master seminar Scientific Computing
Sem Mulder - No inflation EnKF
11:00-12:00
HFG 610
Friday Fish
Charlotte Kirchhoff-Lukat - Branes with boundary and symplectic methods for stable generalised complex manifolds
Generalised complex geometry (introduced by Hitchin and Gualtieri in the early 2000's) interpolates between ordinary complex and symplectic geometry. Stable generalised complex manifolds (first introduced by Cavalcanti and Gualtieri in 2015) provide a class of examples of generalised complex manifolds that admits neither a symplectic nor a complex structure. Their generalised complex structure is, up to gauge equivalence, fully determined by a Poisson structure which is symplectic everywhere except on a real codimension 2 submanifold. I will describe how to generalise a range of symplectic techniques to these manifolds, and describe their natural generically Lagrangian submanifolds, in particular a new type called Lagrangian brane with boundary. I will discuss local deformations and how such branes might arise as objects of a Fukaya category for certain stable generalised complex manifolds.
12:00-13:00
BBG 106
Master seminar Scientific Computing
Sangeetika Ruchi - Supermodelling
13:00-15:00
HFG 610
Friday Fish
Kay Werndli - Functorial operations and the Microsupport of Sheaves
First, we quickly review some functorial operations of sheaves on a space, such as (derived) tensor products and some of the six Grothendieck operations. Afterwards, we investigate the interaction of these operations with the microsupport of sheaves on a manifold.
Tuesday, November 28, 2017
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Geometry and Algebra
Chloe Martindale (Technische Universiteit Eindhoven) - tba
Wednesday, November 29, 2017
10:00-11:45
HFG 611
Guest Lecture
Ruud van der Pas (Oracle) - Shared Memory Parallel Performance To The Extreme
Abstract:
In this talk, we explore the boundaries of shared memory parallelization.
Through several real-world case studies we show what it takes to make Tera Byte sized memory problems scale when using up to 2,048 threads in a single SPARC based system.

As will be explained, and demonstrated, to achieve this kind of scalability, memory driven optimizations are crucial, but processor pipeline operations like atomic operations, cannot be ignored either.

Biography: Ruud van der Pas is Distinguished Engineer at Oracle, Santa Clara, CA, USA.
He is an expert on shared-memory paralllel programming and author of the recently published book "Using OpenMP—The Next Step”, MIT Press October 2017.

The guest lecture is part of the Mastermath course Parallel Algorithms and is open to all interested. The lecture is followed by a question and answer session.
For more information: Rob Bisseling ( r.h.bisseling@uu.nl )
Thursday, November 30, 2017
16:00-17:00
HFG 611
Complex Systems Seminar
Odo Diekmann (UU) - TBA
Title:
Abstract:
Friday, December 1, 2017
11:00-12:00
BBG 106
Master seminar Scientific Computing
Kilian Bakker - Variational data assimilation
12:00-13:00
BBG 106
Master seminar Scientific Computing
Hanna Liu - Data assimilation on slow manifold
Tuesday, December 5, 2017
13:15-14:00
HFG 610
SIAM Student Chapter talk
Nick Luiken - Efficient Methods for Determining the Regularization Parameter in Inverse Problems
Inverse problems deal with retrieving intrinsic properties of dynamical
systems from measured data. Often, these problems are ill-posed which
means that a solution either doesn’t exist, is not unique, or is highly sensitive
to small perturbations in the data. To solve these ill-posed inverse
problems a method called regularization is used. Regularization is the
process of adding prior knowledge to the problem to stabilize it. We focus
on so-called Tikhonov regularization. The importance of the prior
knowledge is controlled by the regularization parameter. Choosing this
parameter is not an easy process: it is a highly nonlinear problem and
there is no physical meaning attached it. We discuss various methods
for choosing the regularization parameter and describe how to efficiently
estimate it.
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
Seminar Geometry and Analysis - tba
tba
Thursday, December 7, 2017
16:00-17:00
HFG 611
Complex Systems Seminar
Jan Bouwe van den Berg (VU) - TBA
Title:
Abstract:
Friday, December 8, 2017
13:15-14:15
Duistermaat
Extra Number Theory Talk
Jens Forsgard (Geneve) - t.b.a.
Monday, December 11, 2017
08:59-10:40
BBG023
Orientation on Mathematical Research Student Presentations (a-c)
09:00-09:30
(a) Grassmannians and Representation Theory of GL(n)
09:35-10:05
(b) The Poincare conjecture
10:10-10:40
(c) Weapons of Math Destruction
16:00-18:00
Ruppert 042
Movie preview
Galois - Story of a revolutionary mathematician
Tuesday, December 12, 2017
15:30-16:00
HFG Library
Institute Tea
Monday, December 18, 2017
08:59-10:40
BBG023
Orientation on Mathematical Research Student Presentations (a-c)
09:00-09:30
(a) Metastability through random walks
09:35-10:05
(b) Addition of ordinals
10:10-10:40
(c) Multiple zeta values
Tuesday, December 19, 2017
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
Seminar Geometry and Analysis - tba
tba
Tuesday, December 26, 2017
15:30-16:00
HFG Library
Institute Tea
Tuesday, January 2, 2018
15:30-16:00
HFG Library
Institute Tea
Friday, January 5, 2018
13:15-14:15
Duistermaat
Extra Number Theory Talk
Valentijn Karemaker (UPenn) - Dynamics of Belyi maps
Abstract: A (genus 0) Belyi map is a finite map from the projective line to itself, branched exactly at 0, 1, and infinity. Such maps can be described combinatorially by their generating systems.
Assuming further that 0, 1, and infinity are both fixed points and the unique ramification points above 0, 1, and infinity respectively yields dynamical Belyi maps, since the resulting maps can be iterated and will therefore exhibit dynamical behaviour.
We will discuss several results on the dynamics, reductions, and monodromy of dynamical Belyi maps, and the interplay between these.
(This is joint work with J. Anderson, I. Bouw, O. Ejder, N. Girgin, and M. Manes.)
Monday, January 8, 2018
08:59-10:05
BBG023
Orientation on Mathematical Research Student Presentations (a-b)
09:00-09:30
(a) DNA of pathogens helps to infer transmission paths
09:35-10:05
(b) Apollonian circle packings and the local-global conjecture
Tuesday, January 9, 2018
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
t.b.a. () - t.b.a.
Monday, January 15, 2018
08:59-10:40
BBG023
Orientation on Mathematical Research Student Presentations (a-c)
09:00-09:30
(a) Evolutionary Game Theory on networks
09:35-10:05
(b) S-immersions and the h-principle
10:10-10:40
(c) The Fermi-Pasta-Ulam problem
Tuesday, January 16, 2018
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
t.b.a. () - t.b.a.
Monday, January 22, 2018
08:59-10:40
BBG023
Orientation on Mathematical Research Student Presentations (a-c)
09:00-09:30
(a) An alternative probability theory based on belief functions
09:35-10:05
(b) The homotopy transfer theorem
10:10-10:40
(c) Supersingular Isogeny Diffie–Hellman
Tuesday, January 23, 2018
12:00-13:00
HFG Library
Bring Your Own Lunch (BYOL)
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
Julie Desjardins (MPIM Bonn) - t.b.a.
Thursday, January 25, 2018
16:00-17:00
HFG 611
Complex Systems Seminar
Isabelle Schneider (Berlin) - TBA
Title:
Abstract:
Tuesday, January 30, 2018
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
Cecília Salgado (MPIM Bonn/Instituto de Matemática - UFRJ) - t.b.a.
Tuesday, February 6, 2018
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
Leila Schneps (Parijs) - t.b.a.
Tuesday, February 13, 2018
15:30-16:00
HFG Library
Institute Tea
16:00-17:00
HFG 610
Utrecht Geometry Center Seminar
t.b.a. () - t.b.a.
Tuesday, February 20, 2018
12:00-13:00
HFG Library
Bring Your Own Lunch (BYOL)
15:30-16:00
HFG Library
Institute Tea
Tuesday, February 27, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, March 6, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, March 13, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, March 20, 2018
12:00-13:00
HFG Library
Bring Your Own Lunch (BYOL)
15:30-16:00
HFG Library
Institute Tea
Tuesday, March 27, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, April 3, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, April 10, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, April 17, 2018
12:00-13:00
HFG Library
Bring Your Own Lunch (BYOL)
15:30-16:00
HFG Library
Institute Tea
Tuesday, April 24, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, May 1, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, May 8, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, May 15, 2018
15:30-16:00
HFG Library
Institute Tea
Tuesday, May 22, 2018
12:00-13:00
HFG Library
Bring Your Own Lunch (BYOL)
15:30-16:00
HFG Library
Institute Tea