activity
20242026
collaborators

6 papers

math.AP2026

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…

math.AP2026

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…

math.FA2025

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…

math.FA2025

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…

math.FA2024

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 composit…

math.FA2024

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.…