Non-self-adjointness of the Klein-Gordon operator on a globally hyperbolic and geodesically complete manifold. An example
arXiv:1904.03691
Abstract
We describe a Lorentzian manifold that is globally hyperbolic and geodesically complete, but such that the (minimally coupled) Klein-Gordon operator with the standard domain is not essentially self-adjoint.
arXiv comment20 pages, no figures, rewritten extended version, references added