Weighted Orlicz-Poincaré inequalities in product spaces
Lucas Yong
TL;DR
The work addresses the problem of establishing weighted Orlicz-Poincaré inequalities on product spaces, providing necessary and sufficient conditions in terms of one-dimensional constants $K_{p_i,Φ}(μ_i,ν_i,w_i)$ and a two-dimensional gauge-norm framework. The approach generalizes the Chuawheeden framework to Orlicz spaces, employing repeated-norm tools and submultiplicativity of $Φ$ with convex $Γ_i(t)=Φ(t^{1/p_i})$ to derive a two-dimensional bound on $\| f - f_{\nu,av} \|_{L_μ^Φ(I\times J)}$ via the directional derivatives $∂_{x_1}f$ and $∂_{x_2}f$. The main results show that finiteness of the 1D constants yields the two-variable inequality, and, under invertibility of $Φ$, a necessity direction as well, thereby linking product-space regularity to constituent one-dimensional conditions. This provides a framework for regularity theory of degenerate PDEs on product domains using Orlicz-Sobolev bounds.
Abstract
This article is a follow-up to arXiv:2304.04373. We establish necessary and sufficient conditions for weighted Orlicz-Poincaré inequalities in product spaces. These results follow the work of Chua and Wheeden, who established similar results for weighted Poincaré inequalities in product spaces.
