activity
20192022
collaborators

6 papers

math.AP2022

Stability of solutions to obstacle problems with generalized Orlicz growth

Petteri Harjulehto, Arttu Karppinen

We consider nonlinear equations having generalized Orlicz growth (also known as Musielak--Orlicz growth). We prove that if differential operators converge locally u…

math.FA2021

Fractional operators and their commutators on generalized Orlicz spaces

Arttu Karppinen

In this paper we examine boundedness of fractional maximal operator. The main focus is on commutators and maximal commutators on generalized Orlicz spaces for fractional maximal fu…

math.FA2021

Sharp growth conditions for boundedness of maximal function in generalized Orlicz spaces

Petteri Harjulehto, Arttu Karppinen

We study sharp growth conditions for the boundedness of the Hardy-Littlewood maximal function in the generalized Orlicz spaces. We assume that the generalized Orlicz function $ϕ(x,…

math.AP2020

Hölder continuity of the minimizer of an obstacle problem with generalized Orlicz growth

Arttu Karppinen, Mikyoung Lee

We prove local - and -regularity for the local solution to an obstacle problem with non-standard growth. These results cover as special cases standard, variable e…

math.AP2020

Removable sets in elliptic equations with Musielak-Orlicz growth

Iwona Chlebicka, Arttu Karppinen

We characterize, in the terms of intrinsic Hausdorff measures, the size of~removable sets for Hölder continuous solutions to elliptic equations with Musielak-Orlicz growth. In the…

math.AP2019

Global continuity and higher integrability of a minimizer of an obstacle problem under generalized Orlicz growth conditions

Arttu Karppinen

We prove continuity up to the boundary of the minimizer of an obstacle problem and higher integrability of its gradient under generalized Orlicz growth. The result recovers similar…