Special seminar on the occasion of the 65th birthday of N. Nadirashvili

Dear Colleagues,

It is our pleasure to invite you to participate in the Special Session of the Montreal-Quebec Analysis Seminar in honour of the 65th birthday of our friend and collaborator Nikolai Nadirashvili.

The program (see details below) includes talks by Aleksandr Logunov (Princeton) and Vladimir Sverak (Minnesota), followed by a Zoom banquet.

We would appreciate it if you could say a few words about Nikolai during the banquet - please let us know if you would be able to do it.

Looking forward to seeing you at the seminar.

Best wishes,

Dima Jakobson & Iosif Polterovich

Alexandr Logunov (Princeton)
Title: Nodal sets, Quasiconformal mappings and how to apply them to Landis' conjecture.
Abstract: A while ago Nadirashvili proposed a beautiful idea how to attack problems on zero sets of Laplace eigenfunctions using quasiconformal mappings, aiming to estimate the length of nodal sets (zero sets of eigenfunctions) on closed two-dimensional surfaces. The idea have not yet worked out as it was planned. However it appears to be useful for Landis' Conjecture. We will explain how to apply the combination of quasiconformal mappings and zero sets to quantitative properties of solutions to $\Delta u + V u =0 on the plane, where $V$ is a real, bounded function. The method reduces some questions about solutions to Shrodinger equation $\Delta u + V u =0$ on the plane to questions about harmonic functions. Based on a joint work with E.Malinnikova, N.Nadirashvili and F. Nazarov.
 

11:00-11:50am, Eastern time. Vladimir Sverak (Minneapolis)

Titile: Liouville theorems for the Navier-Stokes equations
Abstract: Assume u is a smooth, bounded, and divergence-free field on R^3 satisfying the steady Navier-Stokes equation -\Delta u +u\nabla u + \nabla p=0 (for a suitable function p). Does u have to be constant? We still don't know. Interesting things are known and Nikolai made important contributions to our knowledge concerning this question. Similar problems can also be considered for various model equations. The lecture will concern various aspects of this problem.

12:15-13:30, Eastern time: Zoom banquet

FOR ZOOM MEETING INFORMATION PLEASE CONTACT dmitry.jakobson [at] mcgill.ca