OCTOBER 4

Dawid Kielak (University of Oxford)
Fibring in group theory and topology

I will introduce the topological concept of fibring over the circle, and its algebraic counterpart. I will then discuss the role fibring played in Thurston's programme of understanding 3-manifolds, and how the algebraic approach can play a similar role in understanding low dimensional groups.

OCTOBER 11

Maciej Dołęga (IMPAN Kraków)
Enumerative combinatorics – how enumeration helped to discover new bridges in mathematics

In my talk I am going to describe enumerative combinatorics – the area that studies problems that were natural and interesting already for ancient mathematicians but has seen a very quick development in recent years. I will focus on these recent developments and I will describe two examples how enumerative combinatorics helped to build new bridges and fascinating directions of research in probability, representation theory and enumerative geometry.

OCTOBER 18

Grigor Sargsyan (IMPAN Gdańsk)
Forcing Axioms and Determinacy Axioms: towards a unified theory of infinity

Forcing Axioms are axioms of infinity generalizing the Baire Category Theorem. They have been proposed to mitigate the effect of forcing, and since then have been very useful in solving wide range of problems in many areas of mathematics. Determinacy Axioms are game theoretic axioms asserting the determinacy of infinite two player games. They resolve classical questions from analysis. They are fundamentally rooted in different mathematical ideas, depict radically different pictures of the universe, solve mathematical problems according to the prevailing intuition of the practitioners and are logically incompatible, creating deep ambiguities in our understanding of infinity. In this talk, we will describe an approach to unify them. 

OCTOBER 25

Šárka Nečasová (Czech Academy of Sciences)
On the motion of fluid in a moving domain, applications to fluid structure, questions of uniqueness, regularity, and collisions

Problems of fluid flow inside a moving domain deserve a lot of interest as they appear in many practical applications. Such problems can also be seen as a preparation step for research of fluid-structure interaction problems. Research of the compressible version of the Navier-Stokes system dates back to the nineties when the groundbreaking result of the existence of the global weak solutions to the compressible barotropic Navier–Stokes system on a fixed domain was proved by P. L. Lions and, later, by E. Feireisl and collaborators who extended the existence result to more physically relevant state equations. After that the theory of weak solutions was extended to the problem of fluid flow inside a moving domain. Such existing theory was applied to more complicated problem e.g. to the interaction between system of heat conducting fluid with a shell of Koiter type, or into the case of two compressible mutually noninteracting fluids and a shell of Koiter type encompassing a time dependent 3D domain filled by the fluids. Moreover, the theory of compressible fluids filling the smooth bounded domain where inside of a domain rigid body/bodies is/are moving and the motion satisfies the conservation of force and momentum was studied, and some questions arise in these problems e.g. uniqueness, regularity. Even, in the case of an incompressible fluid with moving a rigid body the problem cannot be treated easily since the physical domain is time-dependent. Another very important question is a problem of collision. What we can show? It is possible to prove collision or to show no-collision result.

NOVEMBER 8

Jakub Skrzeczkowski (University of Oxford)
Nonlocal PDEs everywhere!

Nonlocal PDEs (partial differential equations) are a class of equations combining local (say, a function or its derivative evaluated at the given point) and global quantities (say, an integral of the function). I will discuss several areas where such equations arise, including mathematical physics (derivations of equations), numerical analysis (particle-type method for diffusion) and statistics (analysis of the recently proposed Stein variational gradient descent method for sampling). Several open problems will be discussed and some partial solutions will be proposed. 

NOVEMBER 15

Boban Velic̆ković (CNRS/Université Paris Cité)
Higher derived limits

NOVEMBER 22
Barbara and Jaroslav Zemanek Prize Award Ceremony

14:15–15:15   Introductory lecture

Eric Ricard (CNRS/Caen)
Weak type inequalities in non commutative analysis

We will introduce the field of non commutative analysis, where one replaces function spaces by operators algebras and related objects. There have been quite a lot of developments in the last 20 years thanks to operator spaces theory and especially works by Pisier and Junge. As in harmonic analysis, most of the results  are obtained from end point estimates but people considered BMO spaces  as much easier than weak L_1 until Leonard Cadilhac came up with new ideas in his thesis.  

15:45–16:45    Lecture of the laureate

Léonard Cadilhac (Sorbonne Université)
Non-commutative maximal functions and ergodic theory

In non-commutative analysis, maximal inequalities were first formulated in the 70's but their systematic study only began 30 years later in works of Pisier, Junge and Xu. Since a family of positive operators does not necessarily admit a supremum, maximal functions offer many challenges when trying to generalize their theory from standard measure spaces to non-commutative ones. This is seen in their very definition, in their interpolation properties, and in the techniques employed to prove them. In this talk, I will illustrate this facts, mainly focusing on a maximal function coming from the ergodic theory of group actions. 

DECEMBER 6

Mikołaj Frączyk (Uniwersytet Jagielloński)
Large subgroups in higher rank

Let G be a higher-rank semisimple Lie group (for example, SL_n(R), n > 2). The famous Margulis' arithmeticity theorem allows us to more or less classify the lattices of G. On the other hand, our understanding of infinite covolume discrete subgroups of G is far from complete. It seems that in higher rank, it is hard to find examples of "large" discrete subgroups other than lattices. It is natural to wonder whether there are new rigidity statements that would explain this situation. In my talk, I'll make this question more precise and present several instances of such rigidity phenomena, for example, my joint work with Gelander on confined discrete subgroups and the joint work with Minju Lee on discrete subgroups with finite Bowen-Margulis-Sullivan measure.

DECEMBER 13

Przemysław Wojtaszczyk (IMPAN Warszawa)
Nonlinear widths; mix of topology, Banach spaces and numerical algorithms

DECEMBER 20

Jakub Witaszek (Princeton University)
The interplay between complex and arithmetic singularities

JANUARY 10

Mateusz Kwaśnicki (Wrocław University of Science and Technology)

JANUARY 31

Piotr Miłoś (IMPAN Warszawa / IDEAS NCBR)