On the spectral stability of finite coverings

We prove the non-existence of new eigenvalues in $[0,\mathrm{\Lambda }]$ for specific and random finite coverings of a complete and connected Riemannian manifold $M$ with Ricci curvature bounded from below, where $\mathrm{\Lambda }$ is any positive number below the essential spectrum of $M$ and the spectrum of the universal cover of $M$, provided the representation theory of the fundamental group of $M$ satisfies certain conditions.