L p positivity preservation and self-adjointness of Schrödinger operators on incomplete Riemannian manifolds

The aim of this paper is to prove a qualitative property, namely the preservation of positivity, for Schrödinger-type operators acting on Lᵖ functions defined on (possibly incomplete) Riemannian manifolds. A key assumption is a control of the behaviour of the potential of the operator near the Cauchy boundary of the manifolds. As a by-product, we establish the essential self-adjointness of such operators, as well as its generalization to the case p 2, i. e. the fact that smooth compactly supported functions are an operator core for the Schrödinger operator in Lᵖ.