On two functionals involving the maximum of the torsion function

Abstract

In this paper we investigate upper and lower bounds of two shape functionals involving the maximum of the torsion function. More precisely, we consider $T(\Omega )/(M(\Omega )|\Omega |)$ and $M(\Omega ){\lambda }_1(\Omega )$, where $\Omega$ is a bounded open set of ${\mathbb{R}}^d$ with finite Lebesgue measure $|\Omega |$, $M(\Omega )$ denotes the maximum of the torsion function, $T(\Omega )$ the torsion, and ${\lambda }_1(\Omega )$ the first Dirichlet eigenvalue. Particular attention is devoted to the subclass of convex sets.