Sharp embeddings and existence results for Logarithmic $p$-Laplacian equations with critical growth
Rakesh Arora, Jacques Giacomoni, Hichem Hajaiej, Arshi Vaishnavi
TL;DR
This work develops a nonlinear variational framework for the logarithmic $p$-Laplacian, introducing a new $p$-logarithmic Sobolev inequality and establishing optimal continuous and compact embeddings of the associated energy space into Orlicz-type spaces. These embeddings enable handling of critical logarithmic nonlinearities and yield existence and, in some regimes, uniqueness of least-energy solutions for Brezis–Nirenberg-type and logistic-type problems driven by the logarithmic operator. The authors further study the small-order limit of weighted nonlocal problems involving the fractional $p$-Laplacian, showing convergence of least-energy solutions to limiting problems governed by $L_{ riangle_p}$ as $s\to0^+$. Collectively, the results extend known linear theories to a broader nonlinear variational setting and provide nonlinear analogues of prior log-Sobolev and embedding results, with potential applications in nonlocal models and logarithmic-type nonlinear phenomena.
Abstract
In this paper, we derive a new $p$-Logarithmic Sobolev inequality and optimal continuous and compact embeddings into Orlicz-type spaces of the function space associated with the logarithmic $p$-Laplacian. As an application of these results, we study a class of Dirichlet boundary value problems involving the logarithmic $p$-Laplacian and critical growth nonlinearities perturbed with superlinear-subcritical growth terms. By employing the method of the Nehari manifold, we prove the existence of a nontrivial weak solution. Lastly, we conduct an asymptotic analysis of a weighted nonlocal, nonlinear problem governed by the fractional $p$-Laplacian with superlinear or sublinear type non-linearity, demonstrating the convergence of least energy solutions to a non-trivial, non-negative least energy solution of a Brezis-Nirenberg type or logistic-type problem, respectively, involving the logarithmic $p$-Laplacian as the fractional parameter $s \to 0^+$. The findings in this work serve as a nonlinear analogue of the results reported in \cite{Angeles-Saldana, Arora-Giacomoni-Vaishnavi, Santamaria-Saldana}, thereby extending their scope to a broader variational framework.
