[LIBRO][B] Harmonic analysis in operator algebras and its applications to index theory and topological solid state systems

H Schulz-Baldes, T Stoiber - 2022 - books.google.com
This book contains a self-consistent treatment of Besov spaces for W*-dynamical systems,
based on the Arveson spectrum and Fourier multipliers. Generalizing classical results by …

Classifying the dynamics of architected materials by groupoid methods

B Mesland, E Prodan - Journal of Geometry and Physics, 2024 - Elsevier
We consider synthetic materials consisting of self-coupled identical resonators carrying
classical internal degrees of freedom. The architecture of such material is specified by the …

A dynamical approach to sampling and interpolation in unimodular groups

U Enstad, S Raum - Transactions of the American Mathematical Society, 2025 - ams.org
We introduce a notion of covolume for point sets in locally compact groups that
simultaneously generalizes the covolume of a lattice and the reciprocal of the Beurling …

[HTML][HTML] Sums of regular self-adjoint operators in Hilbert-C⁎-modules

M Lesch, B Mesland - Journal of Mathematical Analysis and Applications, 2019 - Elsevier
We introduce a notion of weak anticommutativity for a pair (S, T) of self-adjoint regular
operators in a Hilbert C⁎-module E. We prove that the sum S+ T of such pairs is self-adjoint …

Topological lattice defects by groupoid methods and Kasparov's KK-theory

E Prodan - Journal of Physics A: Mathematical and Theoretical, 2021 - iopscience.iop.org
The bulk-boundary and a new bulk-defect correspondence principles are formulated using
groupoid algebras. The new strategy relies on the observation that the groupoids of lattices …

A groupoid approach to interacting fermions

B Mesland, E Prodan - Communications in Mathematical Physics, 2022 - Springer
We consider the algebra Σ˙(L) generated by the inner-limit derivations over the GICAR
algebra of a fermion gas populating an aperiodic Delone set L. Under standard physical …

A space-adiabatic approach for bulk-defect correspondences in lattice models of topological insulators

DP Ojito, E Prodan, T Stoiber - arxiv preprint arxiv:2410.24097, 2024 - arxiv.org
In space-adiabatic approaches one can approximate Hamiltonians that are modulated
slowly in space by phase-space functions that depend on position and momentum. In this …

Localised module frames and Wannier bases from groupoid Morita equivalences

C Bourne, B Mesland - Journal of Fourier Analysis and Applications, 2021 - Springer
Following the operator algebraic approach to Gabor analysis, we construct frames of
translates for the Hilbert space localisation of the Morita equivalence bimodule arising from …

C*-framework for higher-order bulk-boundary correspondences

DP Ojito, E Prodan, T Stoiber - arxiv preprint arxiv:2406.04226, 2024 - arxiv.org
A typical crystal is a finite piece of a material which may be invariant under some point
symmetry group. If it is a so-called intrinsic higher-order topological insulator or …

A spectral localizer approach to strong topological invariants in the mobility gap regime

T Stoiber - arxiv preprint arxiv:2410.22214, 2024 - arxiv.org
Topological phases of gapped one-particle Hamiltonians with (anti)-unitary symmetries are
classified by strong topological invariants according to the Altland-Zirnbauer table. Those …