13 papers
Normal covering spaces with maximal bottom of spectrum
Panagiotis Polymerakis
We study the property of spectral-tightness of Riemannian manifolds, which means that the bottom of the spectrum of the Laplacian separates the universal covering space from any ot…
Bottom of spectra and coverings of orbifolds
Werner Ballmann, Panagiotis Polymerakis
We discuss the behaviour of the bottom of the spectrum of scalar Schrödinger operators under Riemannian coverings of orbifolds. We apply our results to geometrically finite and to…
On the Steklov spectrum of covering spaces and total spaces
Panagiotis Polymerakis
We show the existence of a natural Dirichlet-to-Neumann map on Riemannian manifolds with boundary and bounded geometry, such that the bottom of the Dirichlet spectrum is positive.…
The spectrum of the Laplacian and volume growth of proper minimal submanifolds
G. Pacelli Bessa, Vicent Gimeno, Panagiotis Polymerakis
We give upper bounds for the bottom of the essential spectrum of properly immersed minimal submanifolds of in terms of their volume growth. Our result improves the…
On the essential spectrum of differential operators over geometrically finite orbifolds
Werner Ballmann, Panagiotis Polymerakis
We discuss the essential spectrum of essentially self-adjoint elliptic differential operators of first order and of Laplace type operators on Riemannian vector bundles over geometr…
On the differential form spectrum of geometrically finite orbifolds
Werner Ballmann, Panagiotis Polymerakis
We derive lower bounds for the essential spectrum of the Hodge-Laplacian on geometrically finite orbifolds and their suborbifolds.