On a class of critical double phase problems

TL;DR

This paper investigates a class of double phase problems with critical growth, establishing the existence of infinitely many solutions with negative energy for certain parameter ranges using variational and topological methods.

Contribution

It introduces new existence results for solutions to double phase problems involving critical growth, employing advanced variational and topological techniques.

Findings

Existence of infinitely many solutions for certain parameter ranges.

Solutions have negative energy values.

Results extend understanding of double phase problems with critical growth.

Abstract

In this paper we study a class of double phase problems involving critical growth, namely $-\text{div}\big(|\nabla u|^{p-2} \nabla u+ \mu(x) |\nabla u|^{q-2} \nabla u\big)=\lambda|u|^{\vartheta-2}u+|u|^{p^*-2}u$ in $\Omega$ and $u= 0$ on $\partial\Omega$, where $\Omega \subset \mathbb{R}^N$ is a bounded Lipschitz domain, $1<\vartheta<p<q<N$, $\frac{q}{p}<1+\frac{1}{N}$ and $\mu(\cdot)$ is a nonnegative Lipschitz continuous weight function. The operator involved is the so-called double phase operator, which reduces to the $p$-Laplacian or the $(p,q)$-Laplacian when $\mu\equiv 0$ or $\inf \mu>0$, respectively. Based on variational and topological tools such as truncation arguments and genus theory, we show the existence of $\lambda^*>0$ such that the problem above has infinitely many weak solutions with negative energy values for any $\lambda\in (0,\lambda^*)$.