On Pólya’s inequality for torsional rigidity and first Dirichlet eigenvalue
Vortrag von Prof. Dr. Michiel van den Berg Datum: 15.09.16 Zeit: 14.20 - 15.10 Raum: Y16G05
Let $\Omega $ be an open set in Euclidean space with finite Lebesgue measure
$|\Omega |$. We obtain some properties of the set function $F : \Omega
\rightarrow {\mathbb R}^+ $ defined by
$$ F(\Omega ) = \frac{T(\Omega ) \lambda _1(\Omega)}{|\Omega |} ,$$
where $T(\Omega )$ and $\lambda_1(\Omega )$ are the torsional rigidity and first
eigenvalue of the Dirichlet Laplacian respectively. For any $m = 2, 3, \ldots $
and $\epsilon \in (0, 1)$ we construct an open set $\Omega _\epsilon \subset
{\mathbb R}^m$ such that $F(\Omega _\epsilon ) \geq 1 - \epsilon $.
This is joint work with Enzo Ferone, Carlo Nitsch and Cristina Trombetti.