2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/139538Non-Hermitian Hamiltonians H possess the real (i.e., observable) spectra inside certain specific domains of parameters D. In general, the determination of their observability-horizon boundaries is difficult. We list the pseudo-Hermitian real N by N matrix Hamiltonians for which the prototype horizons are defined by closed analytic formulae.21 ppQuantum Physicstext