W. Hansen

activity

20062023

most citedUnavoidable sets and harmonic measures living on small sets

16 citations · 34 across the 17 of their papers we have counts for

collaborators

23 papers

math.PR2023

Positive harmonically bounded solutions for semi-linear equations

Wolfhard Hansen, Krzysztof Bogdan

For open sets $U$ in some space $X$ , we are interested in positive solutions to semi-linear equations $Lu = φ (\cdot, u) μ$ on $U$ . Here $L$ may be an elliptic or parabolic operator of…

math.FA2022

Compactness of integral operators and uniform integrability on measure spaces

Wolfhard Hansen

Let $(E, E, μ)$ be a measure space and $G : E \times E \to [0, \infty]$ be measurable. Moreover, let $F_{u i}$ denote the set of all $q \in E^{+}$ (measurabl…

math.AP2019★ 1 cited

Equicontinuity of harmonic functions and compactness of potential kernels

Wolfhard Hansen

Within the framework of balayage spaces (the analytical equivalent of nice Hunt processes), we prove equicontinuity of bounded families of harmonic functions and apply it to obtain…

math.PR2018

Nearly hyperharmonic functions are infima of excessive functions

Wolfhard Hansen, Ivan Netuka

Let $X$ be a Hunt process on a locally compact space $X$ such that the set $E_{X}$ of its Borel measurable excessive functions separates points, every…

math.AP2017

Semipolar sets and intrinsic Hausdorff measure

Wolfhard Hansen, Ivan Netuka

Given a "Green function" $G$ on a locally compact space $X$ with countable base, a Borel set $A$ in $X$ is called $G$ -semipolar, if there is no measure $ν \neq = 0$ supported by $A$ su…

math.AP2017

Nearly hyperharmonic functions and Jensen measures

Wolfhard Hansen, Ivan Netuka

Let $(X, H)$ be a $P$ -harmonic space and assume for simplicity that constants are harmonic. Given a numerical function $φ$ on $X$ which is locally lower bounded, l…