Minimizers of abstract generalized Orlicz--bounded variation energy

TL;DR

This paper investigates the existence and convergence of minimizers for generalized Orlicz--bounded variation energies, especially as the growth parameter approaches 1, using $ ext{BV}$-type spaces and $ ext{Gamma}$-convergence.

Contribution

It establishes the convergence of minimizers in generalized Orlicz--bounded variation spaces as the growth parameter tends to 1, extending previous results with new $ ext{BV}$-type space analysis.

Findings

Minimizers converge in a $ ext{BV}$-type space as $p o 1^+$.

$ ext{Gamma}$-convergence of energy functionals is proven.

Existence of minimizers depends on growth conditions of $ ext{Orlicz}$ functions.

Abstract

A way to measure the lower growth rate of $\varphi:\Omega\times [0,\infty) \to [0,\infty)$ is to require $t \mapsto \varphi(x,t)t^{-r}$ to be increasing in $(0,\infty)$. If this condition holds with $r=1$, then \[ \inf_{u\in f+W^{1, \varphi}_0(\Omega)}\int_\Omega \varphi(x, |\nabla u|) \, dx \] with boundary values $f\in W^{1,\varphi}(\Omega)$ does not necessary have a minimizer. However, if $\varphi$ is replaced by $\varphi^p$, then the growth condition holds with $r=p > 1$ and thus (under some additional conditions) the corresponding energy integral has a minimizer. We show that a sequence $(u_p)$ of such minimizers convergences when $p \to 1^+$ in a suitable $\mathrm{BV}$-type space involving generalized Orlicz growth and obtain the $\Gamma$-convergence of functionals with fixed boundary values and of functionals with fidelity terms. %We complement our results by showing that some previous papers by some of the authors are included in our analysis.