The spectral gap to torsion problem for some non-convex domains

Hua Chen, Peng Luo

In this paper we study the following torsion problem \begin{equation*} \begin{cases} -Δu=1~&\mbox{in}\ Ω,\\[1mm] u=0~&\mbox{on}\ \partialΩ. \end{cases} \end{equation*} Let $Ω\subse…