# Full Seminar Archive

Our regular seminar program covers a broad range of topics from applied mathematics, pure mathematics and statistics. All staff and students are welcome. This page has a complete list of past seminars and a list restricted by year can be accessed via the left-hand menu.

Jan Rozendaal - Australian National University and Institute of Mathematics, Polish Academy of Sciences
It is well known that the solution operators $\cos(t\sqrt{-\Delta})$ and $\sin(t\sqrt{-\Delta})$ to the wave equation $\partial_{t}^{2}u=\Delta u$ are not bounded on $L^{p}(\mathbb{R}^{n})$, for $n\... Matthias Lesch - Mathematisches Institut, Universität Bonn We state a generalization of the Connes–Tretkoff–Moscovici Rearrangement Lemma and give a surprisingly simple (almost trivial) proof of it. Secondly, we put on a firm ground the multivariable... Xiao Xiong - Institute for Advanced Study in Mathematics, Harbin Institute of Technology The core ingredients of the quantised calculus, introduced by A. Connes, are a separable Hilbert space$H$, a unitary self-adjoint operator$F$on$H$and a$C^*$-algebra$\mathcal{A}$represented... Leonard Cadilhac - Université de Caen Normandie The problem of finding the best constant for Khintchine inequalities with Rademacher variables remained open for 50 years until Haagerup computed them in 1981. For free variables, the problem is... Pierre Portal - ANU Can one use pseudo-differential calculus in situations where no Fourier transform is available? On a manifold, one can use the Euclidean pseudo-differential calculus locally, but can one find a... Edward McDonald - University of New South Wales In 1990 V. Peller made a conjecture concerning a sufficient condition for a function on the real line to be Lipschitz under$L_p$-Schatten class perturbations when$0 < p < 1\$. After reviewing...

Alireza Amini Harandi - University of Isfahan
In this talk, we will discuss some fundamental problems in metric fixed point theory that have been solved and other questions that remain open. The talk will be largely expository.

Mikael Rørdam - Department of Mathematical Sciences, University of Copenhagen
I will give an overview of properties of amenable groups, as well as of the lesser known classes of supramenable groups (introduced by Rosenblatt in 1974), respectively, groups with the fixed point...

Ivan Yaroslavtsev - Delft University of Technology
Due to a classical argument of Doob it is well-known that the periodic Hilbert transform has a representation in terms of stochastic integrals with respect to a 2-dimensional Brownian motion. These...

Sebastiano Don - Università di Padova, Italy
Functions of bounded variations (BV for short) arise naturally in many problems in Calculus of Variations and their notion in general metric spaces has been received considerable attention, so far....