2020 Nov 05

2:30pm to 3:30pm

2021 Jan 13

# Analysis seminar: Tracey Balehowsky (Helsinki)

12:00pm to 1:00pm

2020 Nov 04

# Analysis Seminar: Xavier Lamy (Toulouse) — On relaxed harmonic maps with anisotropy

12:00pm to 1:00pm

## Location:

Zoom
Consider maps $u:R^n\to R^k$ with values constrained in a fixed
submanifold, and minimizing (locally) the energy $E(u)=\int W( abla u)$. Here $W$ is a positive definite quadratic form on matrices.
Compared to the isotropic case $W( abla u)=| abla u|^2$ this may look
like a harmless generalization, but the regularity theory for general
$W$'s is widely open. I will explain why, and describe results with
Andres Contreras on a relaxed problem, where the manifold-valued
constraint is replaced by an integral penalization.
2020 Nov 25

# Analysis Seminar: Massimiliano Morini (Parma) "TBA"

12:00pm to 1:00pm

Zoom
2020 Oct 22

# Colloquium: Ehud de Shalit (HUJI) — Difference equations and elliptic functions

2:30pm to 3:30pm

A power series f is said to satisfy a p-Mahler equation (p>1 a natural number) if it satisfies a functional equation of the form
a_n(x).f(x^{p^n}) + ... + a_1(x).f(x^p) + a_0(x).f(x) = 0
where the coefficients a_i(x) are polynomials. These functional equations were studied by Kurt Mahler with relation to transcendence theory.
2020 Oct 21

# Analysis Seminar: Klas Modin (Chalmers University and the University of Gothenburg) — The structure of groups of diffeomorphisms

12:00pm to 1:00pm

## Location:

Ross 70/Zoom
In 1966 V. Arnold made an astonishing discovery: the incompressible Euler equations describe Riemannian geodesics on the infinite-dimensional “Lie group" of volume-preserving diffeomorphisms. This discovery led to geometric hydrodynamics – a field that today encompasses many equations of mathematical physics, information theory, shape analysis, etc. In this talk I shall address the infinite-dimensional manifold and group structures assigned to spaces of diffeomorphisms. Having such structures in place often enable out-of-the-box local existence and uniqueness results.
2020 Aug 05

# HUJI Set Theory seminar - Uri Abraham

Repeats every week every Wednesday, 3 times .
11:00am to 1:00pm

11:00am to 1:00pm
11:00am to 1:00pm

## Location:

https://huji.zoom.us/s/99500290990

Uri Abraham will continue his talks  about

Coding well ordering of the reals with ladders.
Zoom Meeting Id:  995 0029 0990

The following is a link to the recording of Uri's first talk-

2020 Jul 27

# Combinatorics: Doron Puder (TAU)

2:00pm to 4:00pm

## Location:

https://huji.zoom.us/j/97269425447?pwd=TFhuUkhBYTJsa3BvNzJyZHFBMlZqZz09
Speaker: Doron Puder (TAU)

Title: Random permutations sampled by surface groups
2020 Jul 22

# HUJI Set Theory seminar - Uri Abraham

Repeats every week every Wednesday until Tue Aug 04 2020 .
11:00am to 1:00pm

11:00am to 1:00pm

## Location:

https://huji.zoom.us/s/99500290990

Uri Abraham will continue his talks  about

Coding well ordering of the reals with ladders.
Zoom Meeting Id:  995 0029 0990

The following is a link to the recording of Uri's first talk-

2020 Jul 13

# Combinatorics: Edinah K. Gnang (JHU)

2:00pm to 4:00pm

## Location:

Zoom
Speaker: Edinah K. Gnang (JHU)
Title: On the Kotzig-Ringel-Rosa conjecture
Abstract:
In this talk we describe and motivate the K.R.R. conjecture and describe a functional graph theoretic approach enabling us to tackle the K.R.R. conjecture via a composition lemma.
2020 Jul 20

# Combinatorics: Daniel Kalmanovich (HUJI)

2:00pm to 4:00pm

## Location:

Zoom
Speaker: Daniel Kalmanovich (HUJI)
Title: Cubical polytopes
Abstract:
Convex polytopes have fascinated people for ages, and questions about their combinatorics and their geometry have been widely studied.
2020 Jul 06

# Combinatorics: Xinyu Wu (CMU)

2:00pm to 4:00pm

Speaker: Xinyu Wu (CMU)
Title: Explicit near-fully X-Ramanujan graphs
Abstract:
In this talk I will introduce constructions of finite graphs which resemble some given infinite graph both in terms of their local neighborhoods, and also their spectrum.
2020 Jun 24

# Logic Seminar - Jorge Cely

11:00am to 1:00pm

## Location:

Zoom - ID: 995 8999 9308 Password: 568039
Jorge Cely will speak about the fundamental lemma for spherical Hecke algebras and motivic integration.

Abstract:
2020 Jun 23

# Dalia Terhesiu (Leiden) Mixing rates for Infinite horizon Lorentz maps

2:00pm to 3:00pm

Abstract: I will report on recent results on sharp error rates in the local limit theorem for the Sinai billiard map (one and two dimensional) with infinite horizon. This is joint work with F. Pene. This result allows to also obtain higher order terms and thus, sharp mixing rates in the speed of mixing of dynamically Hölder observables for the planar and tubular infinite horizon Lorentz gases in the map (discrete time) case.

Join Zoom Meeting
Meeting ID: 917 3652 5930