whats is the applications of the minimization of eigenvalue in the real life ( physics,the natural sciences...)

Question

let $\lambda_{1}(\Omega),\lambda{2}(\Omega),\lambda_{3}(\Omega)...$ the eigenvlues of the laplacian Operator with Dirichlet condition on the boundary on $\Omega $

the classical spectrale optimisation problem is : $$ min\{\lambda_{k}(\Omega),\; \Omega\subset \mathbb{R}^N open ,\; |\Omega| = c\;\},$$ where $|.|$denoted the Lebesgue measure , $c>0$, $k \in \mathbb{N}^{\ast}$ and $\lambda_{k}$ is the $k-$eme eigenvalue of Dirichlet-lapalacian on $\Omega$.

I would like to know what is the application of this Problem (For the laplacian or another Operator) in the physics or the natural sciences..

thank you for your answers