16 citations · 91 across the 26 of their papers we have counts for
26 papers
From zero solutions with partially bounded supports to solvability and Runge approximation for partial differential equations
Tomasz Ciás, Thomas Kalmes
The existence of non-trivial solutions of homogeneous partial differential equations with prescribed support properties plays a fundamental role in the theory of linear partial dif…
Mean and pointwise ergodicity for composition operators on rearrangement-invariant spaces
Thomas Kalmes, Dalimil Peša
We study ergodicity of composition operators on rearrangement-invariant Banach function spaces. More precisely, we give a natural and easy-to-check condition on the symbol of the o…
Strongly continuous fields of operators over varying Hilbert spaces
Ali BenAmor, Batu Güneysu, Thomas Kalmes +1
After introducing a natural notion of continuous fields of locally convex spaces, we establish a new theory of strongly continuous families of possibly unbounded self-adjoint opera…
Runge type approximation results for spaces of smooth Whitney jets
Tomasz Ciaś, Thomas Kalmes
We prove Runge type approximation results for linear partial differential operators with constant coefficients on spaces of smooth Whitney jets. Among others, we characterize when…
Power boundedness and related properties for weighted composition operators on
Vicente Asensio, Enrique Jordá, Thomas Kalmes
We characterize those pairs of smooth mappings for which the corresponding weighted composition…
Hypercyclic and mixing composition operators on
Thomas Kalmes, Adam Przestacki
In this paper we characterize mixing composition operators acting on the space of slowly increasing smooth functions. Moreover we relate the mixing prop…
Mean ergodic weighted shifts on Köthe echelon spaces
Thomas Kalmes, Daniel Santacreu
Necessary and sufficient conditions are given for mean ergodicity, power boundedness, and topologizability for weighted backward shift and weighted forward shift operators, respect…
Linear topological invariants for kernels of differential operators by shifted fundamental solutions
Andreas Debrouwere, Thomas Kalmes
We characterize the condition for smooth kernels of partial differential operators in terms of the existence of shifted fundamental solutions satisfying certain properties. T…
Quantitative Runge type approximation theorems for zero solutions of certain partial differential operators
Andreas Debrouwere, Thomas Kalmes
We prove quantitative Runge type approximation results for spaces of smooth zero solutions of several classes of linear partial differential operators with constant coefficients. A…
Linear topological invariants for kernels of convolution and differential operators
Andreas Debrouwere, Thomas Kalmes
We establish the condition for smooth kernels of various types of convolution and differential operators. By the - splitting theorem of Vogt and Wagner, this impli…
Mean ergodic composition operators on spaces of smooth functions and distributions
Thomas Kalmes, Daniel Santacreu
We investigate (uniform) mean ergodicity of weighted composition operators on the space of smooth functions and the space of distributions, both over an open subset of the real lin…
Integrability and Approximability of Solutions to the Stationary Diffusion Equation with Lévy Coefficient
Oliver G. Ernst, Hanno Gottschalk, Thomas Kalmes +2
We investigate the stationary diffusion equation with a coefficient given by a (transformed) Lévy random field. Lévy random fields are constructed by smoothing Lévy noise fields wi…
Boundary values of zero solutions of hypoelliptic differential operators in ultradistribution spaces
Andreas Debrouwere, Thomas Kalmes
We study ultradistributional boundary values of zero solutions of a hypoelliptic constant coefficient partial differential operator on . Our…
Topologizable and power bounded weighted composition operators on spaces of distributions
Thomas Kalmes
We study topologizability and power boundedness of weigh\-ted composition operators on (certain subspaces of) for an open subset of . For the fo…
Dynamics of shift operators on non-metrizable sequence spaces
José Bonet, Thomas Kalmes, Alfred Peris
We investigate dynamical properties such as topological transitivity, (sequential) hypercyclicity, and chaos for backward shift operators associated to a Schauder basis on LF-space…
Power bounded weighted composition operators on function spaces defined by local properties
Thomas Kalmes
We study power boundedness and related properties such as mean ergodicity for (weighted) composition operators on function spaces defined by local properties. As a main application…
An approximation theorem of Runge type for kernels of certain non-elliptic partial differential operators
Thomas Kalmes
For a constant coefficient partial differential operator with a single characteristic direction such as the time-dependent free Schrödinger operator as well as non-degenerat…
Dynamics of weighted composition operators on function spaces defined by local properties
Thomas Kalmes
We study topological transitivity/hypercyclicity and topological (weak) mixing for weighted composition operators on locally convex spaces of scalar-valued functions which are defi…
On Banach spaces of vector-valued random variables and their duals motivated by risk measures
Thomas Kalmes, Alois Pichler
We introduce Banach spaces of vector-valued random variables motivated from mathematical finance. So-called risk functionals are defined in a natural way on these Banach spaces and…
Graph Laplacians do not generate strongly continuous semigroups
Thomas Kalmes, Christoph Schumacher
We show that for graph Laplacians on a connected locally finite simplicial undirected graph with countable infinite vertex set none of the operators $α\,\mathrm{Id}+β…
A short remark on the surjectivity of the combinatorial Laplacian on infinite graphs
Thomas Kalmes
Applying a well-known theorem due to Eidelheit, we give a short proof of the surjectivity of the combinatorial Laplacian on connected locally finite undirected simplicial graph …
A remark on the frequent hypercyclicity criterion for weighted composition semigroups and an application to the linear von Foerster-Lasota equation
Thomas Kalmes
We generalize a result for the translation -semigroup on about the equivalence of being chaotic and satisfying the Frequent Hypercyclicity criterion due to Mangi…
A simple characterization of chaos for weighted composition -semigroups on Lebesgue and Sobolev spaces
Thomas Kalmes
We give a simple characterization of chaos for weighted composition -semigroups on for an open interval . Moreover, we characterize chaos for…
Surjectivity of differential operators and linear topological invariants for spaces of zero solutions
Thomas Kalmes
We provide a sufficient condition for a linear differential operator with constant coefficients to be surjective on and , respectively, where…