## Plenary speakers

Talk title: **The Tikhonov method in gene expression models**

Date & time: Monday, September 2, 2019

The Tikhonov method reduces variables of the complex systems under theassumption that some parameters are small. In the presented gene expressionmodel we will consider two processes: dimer formation and binding to thepromoter. Using the Tikhonov theorem we simplify the entire system to theclassical one in different ways depending on the time scales of the involvedprocesses. More precisely, we prove that the solutions of the full system canbe approximated by the solutions of the reduced systems.

Talk title: **On mathematical gems of Krystyna Kuperberg, and how they got to me**

Date & time: Sunday, September 1, 2019

In the first part of my talk, I would like to offer a discussion of several mathematical discoveries made by Krystyna Kuperberg, and their impact on the field of topology and dynamical systems. A common denominator for them is that they bring together ingenious geometric intuitions and aesthetic execution in construction. Then I would like to share the impact they had on my own research.

Talk title: **Integrable versus non-integrable systems in Celestial Mechanics**

Date & time: Saturday, August 31, 2019

All bodies of the Solar system, either natural or artificial, are endowed by two motions: a revolution around a central object and a rotation about its own spin-axis. Both kinds of motion can be modeled starting with an *integrable* dynamical system. The motion describing the revolution is modeled in a first approximation by Kepler’s two-body problem, which is well known to be integrable with solutions represented by conic trajectories. The motion describing the rotation of a rigid body is known to be integrable at least in three celebrated cases discovered by Euler, Lagrange and Kowalewska.

The integrable approximation represents a first step for the understanding of the motion, but as soon as a more elaborated model is considered, a complex dynamics arise both in orbit and rotation. The stability of such *non-integrable* models can be studied through mathematical methods such as perturbation theories and KAM theorem. We briefly describe such theories and some of their applications to Celestial Mechanics.

Talk title: **Sofia Kowalewska-- the first woman professor holding a university chair**

Date & time: Sunday, September 1, 2019

The talk will present the turbulent life of the famous mathematician Sofia Kowalewskaya -- a strong woman endowed with an original mathematical talent and great inner power for bringing her aspirations to completion. After describing her growing up in Palibino, Moscow and Kaluga we will focus on her "freedom periods" in Saint Petersburg, Heidelberg, Berlin, Goettingen and Stockholm, related to her mathematical career. The talk will be given in Polish and English, with slides in English.

Talk title: **Sofia Kowalewska -the First Lady of PDEs - saves a Cauchy Problem in Riemannian Geometry**

Date & time: Saturday, August 31, 2019

My rather modest engagement in Kovalevskaya's theory goes back to my very early paper with B. Bojarski and R. Kopiecki on Riemannian manifolds and quasiconformal mappings published in the "Proceedings of a Seminar held in Firenze (1980) on Monge-Ampere Equations and Related Topics" .

The basis for the discussion here is the application of Soa Kovalevskaya Theorem in generalization of the so-called Yamabe Problem in Riemannian Geometry.

This sneak preview to be continued.

Talk title: **Asymptotic properties of solutions to nonlinear second–order diﬀerence equations**

Date & time: Monday, September 2, 2019

This speech is devoted to the study of some nonlinear second order diﬀerence equations from asymptotic point of view. In the ﬁrst problem, we consider some generalisation of the discrete version of the classical Sturm-Liouville boundary value problem on half line. Assuming diﬀerent types of growth conditions on a nonlinear part of the equation, we get the existence of a solution to our problem by Schauder’s ﬁxed point theorem. In the second problem, the existence of a solution to a nonlinear second-order equation with prescribed asymptotic behaviour is considered. o(n^{s}), where s ≤ 0, is used as measure of approximation of solutions. The ﬁxed point approach is used to get main theorem. In the last problem, we present the suﬀicient conditions for the existence of a sequence of positive homoclinic solutions to a nonlinear boundary value problem on integers with p_{k}-Laplacian. To achieve our goal the variational technique is used.

Talk title: **Quantitative immersability of Riemann metrics and the infinite hierarchy of prestrained shell models**

Date & time: Sunday, September 1, 2019

Talk title: **Women in PDE's - regularity issues for nonlinear equations and systems**

Date & time: Sunday, September 1, 2019

Talk title: Mathematical thinking and learning

Date & time: Sunday, September 1, 2019

Talk title: **Karen Uhlenbeck and her mathematics Abel Prize 2019**

Date & time: Monday, September 2, 2019

The Abel Prize (a „mathematical Nobel”) for 2019 was awarded to Karen Uhlenbeck.

We will describe her exceptional mathematical career which lead her to the centre of most important developments in mathematics in the last century. Her research started with general problems in the calculus of variations and went through minimal surfaces and harmonic maps to Yang-Mills fields and gauge theory. Her contributions to geometric analysis were crucial in the proofs of revolutionary results of Simon Donaldson in topology with the use of Yang-Mills equations. Gauge theory, invented by physicists and being essential in mathematical physics today, turned out to be an efficient tool for solving problems in topology of 4-manifolds. Some of Karen Uhlenbeck's results used in this field were presented at the International Congress of Mathematicians in Warsaw in 1983.