arXiv subjects

Heikki Hakkarainen

Publications and source records attributed to Heikki Hakkarainen.

4 recordsLinked to original sources

arXiv2014

Stability and continuity of functions of least gradient

In this note we prove that on metric measure spaces, functions of least gradient, as well as local minimizers of the area functional (after modification on a set of measure zero) are continuous everywhere outside their jump sets. As a tool, we develop some stability properties of sequences of least gradient functions. We also apply these tools to prove a maximum principle for functions of least gradient that arise as solutions to a Dirichlet problem.

math.MG↗

arXiv2014

Relaxation and integral representation for functionals of linear growth on metric measure spaces

This article studies an integral representation of functionals of linear growth on metric measure spaces with a doubling measure and a Poincaré inequality. Such a functional is defined through relaxation, and it defines a Radon measure on the space. For the singular part of the functional, we get the expected integral representation with respect to the variation measure. A new feature is that in the representation for the absolutely continuous part, a constant appears already in the weighted Euclidean case. As an application we show that in a variational minimization problem related to the functional, boundary values can be presented as a penalty term.

math.FA↗

arXiv2011

The variable exponent BV-Sobolev capacity

In this article we study basic properties of the mixed BV-Sobolev capacity with variable exponent p. We give an alternative way to define mixed type BV-Sobolev-space which was originally introduced by Harjulehto, Hästö, and Latvala. Our definition is based on relaxing the p-energy functional with respect to the Lebesgue space topology. We prove that this procedure produces a Banach space that coincides with the space defined by Harjulehto et al. for bounded domain and log-Hölder continuous exponent p. Then we show that this induces a type of variable exponent BV-capacity and that this is a Choquet capacity with many usual properties. Finally, we prove that this capacity has the same null sets as the variable exponent Sobolev capacity when p is log-Hölder continuous.

math.CA↗

arXiv2011

Comparisons of relative BV-capacities and Sobolev capacity in metric spaces

We study relations between the variational Sobolev 1-capacity and versions of variational BV-capacity in a complete metric space equipped with a doubling measure and supporting a weak $(1,1)$-Poincaré inequality. We prove the equality of 1-modulus and 1-capacity, extending the known results for $1 < p < \infty$ to also cover the more geometric case $p = 1$. Then we give alternative definitions for variational BV-capacities and obtain equivalence results between them. Finally we study relations between total 1-capacity and versions of BV-capacity.

math.CA↗