Research seminar "Functional analysis, operator theory and dynamical systems"


Winter semester 2024/25

We proceed this semester in a hybrid format on Wednesday.
If you are interested in participating in our seminar, please drop a message.


23.10.2024: Christopher Cedzich (Düsseldorf)
"The unitary almost-Mathieu operator and (possibly) beyond

Format: on zoom, 13:00-14:00.


30.10.2024: Haonan Zhang (University of South Carolina)
"On the Eldan-Gross Inequality"

Format: on zoom, 13:00-14:00.


6.11.2024: Florentin Münch (Leipzig)
"Every Salami has two ends"

Format: on zoom, 13:00-14:00.


13.11.2024: Tao Wang (Fudan University Shanghai)
"Cheeger type inequalities associated with isocapacitary constants on graphs"

Format: on zoom, 13:00-14:00.


27.11.2024: Giulia Meglioli (Bielefeld)
"Uniqueness for the heat equation on infinite graphs"

Format: on zoom, 13:00-14:00.


4.12.2024: Jun Masamune (Tohuku University, Sendai)
"Construction of signed distance functions with an elliptic equation"

Format: on zoom, 13:00-14:00.



Summer semester 2024

10.04.2024: Pavel Exner (Prague)
"Effects of time-reversal invariance violation in quantum graphs"

Format: on zoom, 13:00-14:00.


17.04.2024: Gilad Sofer (Technion Haifa)
"Zero measure Cantor spectrum for Sturmian metric graphs"

Format: on zoom, 13:00-14:00.


08.05.2024: Matthias Täufer (Hagen)
"Anti-Faber-Krahn property for the heat content on metric graphs (or 'Building better batteries')"

Format: on zoom, 13:00-14:00.


29.05.2024: Sven Gnutzmann (Nottingham)
"Quantum information scrambling and chaos induced by a Hermitian matrix "

Format: on zoom, 13:00-14:00.


26.06.2024: Radek Wojciechowski (City U NY)
"Essential self-adjointness of the Laplacian on weighted graphs: harmonic functions, stability, characterizations and capacity"

Format: on zoom, 13:00-14:00.


07.07.2024: Sebastian Boldt (Chemnitz)
"The normal injectivity radius of am embedded hypersurface"

Format: on zoom, 13:00-14:00.



Winter semester 23/24


18.10.2023: Paul Hege (University of Tübingen)
"Computing the spectrum of infinite-volume operators from finite patches"

Format: on zoom, 13:00-14:00.


01.11.2023: Renaud Leplaideur (Université de la Nouvelle-Calédonie)
"Jacaranda and the substreetutions"

Format: on zoom, 11:00-12:00.


08.11.2023: Simon Barthelmé (CNRS, Gipsa-lab)
"Sampling nodes on graphs using Determinantal Point Processes"

Format: on zoom, 13:00-14:00.


15.11.2023: Olaf Post (University of Trier)
"Isospectral magnetic graphs via partition of numbers"

Format: on zoom, 13:00-14:00.


06.12.2023: Konstantin Pankrashkin (University of Oldenburg)
"An embedded trace theorem for infinite metric trees with applications to transmission problems with mixed dimensions"

Format: on zoom, 13:00-14:00.


13.12.2023: Anna Muranova (University of Warmia and Mazury in Olsztyn)
"Markov chains arising from graphs over ordered fields"

Format: on zoom, 13:00-14:00.


10.01.2024: Ujjal Das (Technion Haifa)
"On the optimization of the first weighted eigenvalue"

Format: on zoom, 13:00-14:00.


Winter semester 22/23


2.11.2022: Borbola Gerhat (Czech Technical University in Prague)
"An improved discrete Rellich inequality on the half-line"

Format: on zoom.


17.11.2022: Anna Muranova (Olsztyn)
"Spectrum of discrete Laplacian over an ordered field"

Format: on zoom, 13:00-14:00.


23.11.2022: Ram Band (Technion Haifa)
"Spectral flows and the Robin count deficiency for metric graphs"

Format: on zoom, 13:00-14:00.


30.11.2022: Bernhard Helffer (Nantes)
"Computing nodal deficiency with a refined spectral flow"

Format: on zoom, 13:30-14:30.


7.12.2022: Ron Rosenthal (Technion Haifa)
"Random simplicial complexes of top bounded degree"

Format: on zoom, 13:00-14:00.


14.12.2022: Yehuda Pinchover (Technion Haifa)
"The space of Hardy-weights for quasilinear equations: Maz'ya-type characterization and sufficient conditions for existence of minimizers"

Format: on zoom, 13:30-14:30.


11.1.2023: Shubham Gupta (Imperial College)
"Polya-Szego inequality on 2-D lattice graph"

Format: on zoom, 13:30-14:30.


18.1.2023: Ulrik Enstad (Stockholm U)
"A dynamical approach to density theorems for sampling in unimodular groups"

Format: on zoom, 13:00-14:00.


1.2.2023: Siegfried Beckus (Potsdam)
Maria Weber-Lecture: "Dry Ten Martini Problem for Sturmian Dynamical Systems"

Format: on zoom, 14:15-15:15.


8.2.2023: Peter Stollmann (Chemnitz)
"Regularity results for locally integrable subharmonic functions on local Dirichlet spaces"

Format: on zoom, 13:30-14:30.


Summer semester 2022


20.04.2022: Marius Nietschmann (University of Potsdam)
"Optimal Hardy Inequality for Fractional Laplacians"

Format: on zoom, 13:30-14:30.


27.04.2022: Radoslaw Wojciechowsky (City University NY)
"Graphs and discrete Dirichlet spaces"

Format: on zoom, 10:00-11:00


04.05.2022: Luz Roncal (Bilbao)
"Unique continuation properties for the fractional discrete Laplacian"

Format: on zoom, 13:30-14:30


18.05.2022: Daniel Lenz (U Jena)
"Uniformity of cocycles"

Format: on zoom, 13:30-14:30


25.05.2022: Noema Nicolussi (U Potsdam)
"Laplacians on Riemann surfaces and Graphs"

Format: on zoom, 13:30-14:30


08.06.2022: Lukasz Grabowski (U Leipzig)
"Expansion properties and their applications in ergodic theory"

Format: on zoom, 13:30-14:30


22.06.2022: Anton Gorodetski (UC Irvine)
"Non-stationary Furstenberg Theorem and Anderson Localization"

Format: on zoom, 17:00


29.06.2022: Christoph Richard (FAU Erlangen)
"Leptin densities in amenable groups"

Format: on zoom, 13:30-14:30


06.07.2022: Xueping Huang (U Nanjing)
"Semi-linear elliptic inequalities on weighted graphs"

Format: on zoom, 13:30-14:30


13.07.2022: Christian Seifert (TU Hamburg)
"On some Mathematical Systems Theory in Banach spaces"

Format: on zoom, 13:30-14:30


Winter semester 21/22



13.10.2021: Elias Zimmermann (University of Leipzig)
"Fiber entropy and algorithmic complexity of random orbits"

Format: on zoom, 13:30-14:30.


20.10.2021: Philipp Hake (University of Leipzig)
"Optimal Hardy-type inequalities on lattices in stratified groups"

Format: on zoom, 13:30-14:30.


27.10.2021: Daniel Lenz (University of Jena)
"Dynamical systems with pure point spectrum"

Format: on zoom, 10:00-11:00. NOTE THE CHANGE OF TIME FOR THIS TALK!.


3.11.2021: Christian Rose (University of Bremen)
"Optimal large scale Gaußian upper bounds for heat kernels of unbounded graph Laplacians"

Format: on zoom, 13:30-14:30.


10.11.2021: Florentin Münch (MPI-MIS Leipzig)
"Characterizations of Forman curvature"

Format: on zoom, 13:30-14:30.


17.11.2021: no seminar (Buß- und Bettag)


24.11.2021: Bobo Hua (Fudan U)
"Graphs with positive spectrum"

Format: on zoom, 10:00-11:00. NOTE THE CHANGE OF TIME FOR THIS TALK!.


1.12.2021: Tatiana Nagnibeda (U Geneva)
"Schreier graphs of self-similar groups as source of examples in spectral graph theory"

Format: on zoom, 13:30-14:30.


8.12.2021: Peter Stollmann (TU Chemnitz)

Format: MFO talk on zoom.


15.12.2021: Melchior Wirth (IST Austria)
"Curvature-dimension conditions for quantum Markov semigroups"

Format: on zoom, 13:30-14:30.


5.1.2022: Philipp di Dio (LAAS-CNRS Toulouse)
"Schwartz function valued solution of the Euler and the Navier-Stokes equations"

Format: on zoom, 13:30-14:30.


12.1.2022: Shiwen Zhang (U Minnesota)
"The landscape law for tight binding Hamiltonians"

Format: on zoom, 16:30-17:30.


26.1.2022: Ali Ben Amor
"Spectral asymptotic and positivity for singular Dirichlet-to-Neumann operators"

Format: on zoom, 13:30-14:30.


2.2.2022: Alberto Takase (UC Irvine)
"Schrödinger operators on Cayley graphs"

Format: on zoom, 13:30-14:30.


9.2.2022: Baptiste Devyver (U Grenoble)
"Gradient estimates for the heat kernel on some fractal-like cable systems"

Format: on zoom, 13:30-14:30.


Summer semester 2021


We proceed this semester in an online format on Wednesday.
If you are interested in participating in our seminar, please drop a message.


14.4.2021: Bálint Virág (University of Toronto)
"The sine beta operator and the stochastic zeta function"

Format: on zoom, 13:30-14:30.


21.4.2021: Siegfried Beckus (University of Potsdam)
"Primitive substitutions beyond Abelian groups: The Heisenberg group"

Format: on zoom, 13:30-14:30.


28.4.2021: Marius Lemm (EPFL)
"On optimal Hardy weights for the Euclidean lattice"

Format: on zoom, 13:30-14:30.


5.5.2021: Batu Güneysu (University of Bonn)
"Feynman-Kac formula for first order perturbations of covariant Laplace-type operators"

Format: on zoom, 13:30-14:30.


12.5.2021: Alexander Grigor'yan (University of Bielefeld)
"Path homology on digraphs"

Format: on zoom, 13:30-14:30.


19.5.2021: Jean Bellissard (University of Münster)
"Structure of Delone Sets, a Review"

Format: on zoom, 13:30-14:30.


26.5.2021: Alexey Klimenko (Steklov Mathematical Institute of RAS and NRU Higher School of Economics, Moscow)
"Convergence of Spherical Averages for Actions of Fuchsian Groups"

Format: on zoom, 13:30-14:30.


2.6.2021: Tanja Eisner (University of Leipzig)
"Wiener's lemma along subsequences"

Format: on zoom, 13:30-14:30.


9.6.2021: Safoura Zadeh (MFO Leibniz Fellow)
"On factorization of separating maps on noncommutative Lp-spaces"

Format: on zoom, 13:30-14:30.


23.6.2021: Anush Tserunyan (McGill University Montréal)
"Backward and forward ergodic theorems along trees"

Format: on zoom, 13:30-14:30.


30.6.2021: Moritz Gerlach
"Regularization properties of kernel operators"

Format: on zoom, 13:30-14:30.


14.7.2021: Ori Parzanchevski (Hebrew University Jerusalem)
"Random walks on Ramanujan graphs and complexes"

Format: on zoom, 13:30-14:30.


21.7.2021: Martin Tautenhahn (University of Leipzig)
"Quantitative unique continuation and its application to random operators and control theory"

Format: on zoom, 13:30-14:30.



Winter semester 2020/21


We proceed this semester in a hybrid format on Wednesday.
If you are interested in participating in our seminar, please drop a message.


4.11.2020: Ian Zimmermann (University of Jena)
"Reaction vs. Diffusion: Blow-up of solutions of an abstract semilinear parabolic equation"

Format: on zoom, 13:30-14:30.


11.11.2020: Michael Baake (University of Bielefeld)
"A cocycle approach to the Fourier transform of Rauzy fractals and the point spectrum of Pisot inflation tilings"

Format: on zoom, 13:30-14:30.


18.11.2020: no seminar (Buß- und Bettag)



25.11.2020: Yehuda Pinchover (Technion Haifa)
"On families of optimal Hardy-weights for linear second-order elliptic operators"

Format: on zoom, 13:30-14:30.


2.12.2020: Peter Stollmann (University of Chemnitz)
"Lower bounds for Schrödinger operators: finite vs infinite coupling"

Format: on zoom, 13:30-14:30.


9.12.2020: Yotam Smilansky (Rutgers University)
"Multiscale substitution tilings"

Format: on zoom, 15:00-16:00. NOTE THE CHANGE OF TIME FOR THIS TALK!.


16.12.2020: Florian Fischer (University of Potsdam)
"Reduced Functions, Minimally Thin Sets and a Fatou-Naim-Doob-type Theorem for Schrödinger Operators on Graphs"

Format: on zoom, 13:30-14:30.


13.1.2021: Max von Renesse (University of Leipzig)
"Molecules as Metric Measure Spaces with Kato-Bounded Ricci Curavture"

Format: on zoom, 13:30-14:30.


20.1.2021: Jürgen Voigt (Dresden)
"Hausdorff measure and an inequality due to Maz'ya"

Format: on zoom, 13:30-14:30.


27.1.2021: Radoslaw Wojciechowski (CUNY)
"Essential self-adjointness of the Laplacian on graphs: Liouville properties, stability and characterizations"

Format: on zoom, 15:00-16:00. NOTE THE CHANGE OF TIME FOR THIS TALK!.


3.2.2021: Vadim Alekseev (Dresden)
"Geometry of approximations for sofic groups"

Format: on zoom, 13:30-14:30.




Previous semsters


26.10.2019: Retha Heymann (University of Stellenbosch)
"Multiplikatoren auf Faserräumen und der Extrapolationsraum eines Multiplikators als Beispiel"

Felix-Klein-HS, 13:30-14:30


13.11.2019: Blanca Besoy (Universidad Complutense Madrid)
"Logarithmic interpolation spaces. Duality and applications to Besov spaces."

Felix-Klein-HS, 13:30-14:30


20.11.2019: Buß- und Bettag. No seminar.


27.11.2019: Nils Waterstraat (Universität Halle)
"On the Fredholm Lagrangian Grassmanian, Spectral Flow and ODEs in Hilbert Spaces."



different location : Paulinum P-701, 13:30-14:30


4.12.2019: Max Kämper (TU Dortmund)
"Approximating the integrated density of states of random Schrödinger operators"

Felix-Klein-HS, 13:30-14:30


18.12.2019: Asgar Jamneshan (UC Los Angeles)
"On an uncontable Moore-Schmidt theorem"

Felix-Klein-HS, 13:30-14:30


8.1.2020: Siegfried Beckus (Potsdam)
"When do the spectra of self-adjoint operators converge?"

Felix-Klein-HS, 13:30-14:30


29.1.2020: Henning Bostelmann (York)
"High energy bounds on wave operators"

Felix-Klein-HS, 13:30-14:30