Non linear pseudo-bosons versus hidden Hermiticity. II: The case of unbounded operators

Abstract

A close parallelism between the notions of nonlinear pseudobosons and those of an apparent non-Hermiticity of observables as shown in part I (2011 J. Phys. A: Math. Theor. 44 415305) is demonstrated to survive the transition to the quantum models using an unbounded metric in the so-called standard Hilbert space of states