Dynamics Seminar “A midsummer dynamic’s daydream”

Centro De Giorgi, Pisa, 28 June 2022

The event will take place in person. Those who are unable to be physically present may attend the talk via Zoom by following the link: https://us02web.zoom.us/j/83965821067?pwd=YU9MRHVVMlRQMXZycjVzVGR3VmlXZz09

9:15-10:15

Dong Han Kim (Dongguk University - Seoul)

“Intrinsic Diophantine approximation on circles and spheres”

Abstract: We study Lagrange spectra arising from intrinsic Diophantine approximation of copies of a circle and a sphere. More precisely, we consider three copies of a unit circle embedded in R^2 or R^3 and three copies of a unit sphere embedded in R^3 or R^4. We present a unified framework to connect the Lagrange spectra of these six spaces with the spectra of R and C. Combining this with prior work of Asmus L. Schmidt on the spectra of R and C, we can characterize, for each of the six spectra, the smallest accumulation point and the initial discrete part leading up to it completely. This is joint work with Byungchul Cha.

10-14 october 2022: Big Mapping Class Groups and Diffeomorphism Groups, CIRM, Marseille

Organizers: Kathryn Mann (Cornell University), Andrés Navas (Universidad de Santiago de Chile), Cristóbal Rivas (Universidad de Chile), Michele Triestino (Université de Bourgogne), Ferrán Valdez (Universidad Nacional Autónoma de México).

The meeting is centered on groups that arise in dynamical and geometric contexts, an area which has seen many exciting developments in the past five years. These groups appear in many contexts, ranging from mathematical physics, to dynamical systems, Lie theory and group theory, and ideas and techniques from each area have been fruitfully applied to the others. A major motivating question is to understand to what extent the algebraic structure of an abstract group constrains the possible action of this group on topological spaces. Answering this question involves understanding the structure of diffeomorphism and homeomorphism groups of manifolds. The goal of the conference is to gather people working on the subject (around 70 participants, with at least 20/30 young researchers). The main activities will be 3 minicourses. The subjects of the talks will cover a large list of topics.

3-7 october 2022: School on Dynamical Group Theory, Institut de Mathématiques de Bourgogne, Dijon

Organizers: Joaquín Brum (Universidad de la República), Nicolás Matte Bon (CNRS, Université de Lyon 1), Cristóbal Rivas (Universidad de Chile), Michele Triestino (Université de Bourgogne).

This event is mainly addressed to young researchers, to discover some recent directions in “dynamical group theory”, namely the study of transformation groups and the dynamics of their actions. There will be 3 mini-courses, by Sang-hyun Kim (KIAS), Anne Lonjou (Université Paris-Saclay), Emmanuel Militon (Université Côte d’Azur).

The Women in Math Committee (WiM) of the European Mathematical Society is organising an event called “EMS/WiM Day” within the initiative of “May 12th”, a celebration of women in Mathematics in memory of Maryam Mirzakhani.

The event consists of scientific talks (at the level of a Colloquium talk) of two distinguished speakers, which will take place online on Friday, 20 May 2022 with the following schedule:

14:45 CEST Welcome
15:00 CEST Tara Brendle (Glasgow University, UK)
16:00 CEST Tere M. Seara (UPC, Barcelona, Spain)

The titles and abstracts of the talks are given below.

A website for our workshop DinAmicI VII (June 6-9, 2022, at RISM) is now online at https://www.rism.it/events/dinamici-vii. Please join us and register for the workshop, and check the website from time to time as new information will appear.

Between April 11 and May 12, 2022, Francesco Cellarosi will deliver the PhD course “Randomness in Number Theory: dynamical and probabilistic methods”, at the Department of Mathematics of Università di Bologna and on-line via MS Teams.

Schedule

(All times are 4-6pm Italian time. Room name within the Math Building in parenthesis)

April 11 (Seminario VIII Piano)
April 13 (Aula VII Piano)
April 20 (Bombelli)
April 21 (Seminario VIII Piano)
April 26 (Seminario VIII Piano)
April 28 (Seminario VIII Piano)
May 3 (Seminario VIII Piano)
May 5 (Seminario VII Piano)
May 10 (Bombelli)
May 12 (Seminario VIII Piano)

Program

The course will focus on recent advances concerning the study of random behaviour of number-theoretical sequences. We will mainly focus on the distribution of square-free integers and their generalisations (e.g. k-free, B-free). We will discuss Sarnak’s conjecture on the disjointness of the Mobius function $\mu(n)$ from sequences generated by zero-entropy dynamical systems. We will prove that $\mu^2(n)$ (the indicator of square-free integers) is completely deterministic and study the statistics of its patterns in long intervals. We will also discuss some very recent progress on the distribution of square-free integers in small intervals.

It is a pleasure to announce that our biennial workshop is returning this year.

The workshop “DinAmicI VII” is organised in collaboration with the Riemann International School of Mathematics https://www.rism.it/, and will take place in the days 6-9 June, 2022 at Villa Toeplitz (Varese).

More information will follow, but for now, save the date!

The website of the Quarta Giornata DinAmica, a.k.a. as Fourth DinAmicI Day, a.k.a. 4th DAI Day, is up and running: https://eventi.unibo.it/dinamiciday4

We hope to have as many participants as possible, ideally in presence, or at least online. We ask everyone interested to register at the website.

The organizers

The organizers of the Fourth DAI Day are happy to announce that the event will take place on December 17, 2021 in Parma, from morning to afternoon.

As is tradition by now, there will be seminars, mostly by young speakers and a general assembly of the community, which might or might not contain the official assembly of the UMI Group DinAmicI.

More information will follow, but for now, save the date!

HYBRID CONFERENCE

Differential Geometry, Billiards, and Geometric Optics Géométrie différentielle, billards et optique géométrique

4-8 October 2021, CIRM (Luminy, France)

Website for registration:
https://conferences.cirm-math.fr/2383.html

Events