2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/126428It is believed that unbroken PT symmetry is sufficient to guarantee that the spectrum of a non-Hermitian Hamiltonian is real. We prove that this is not true. We study a Hamiltonian with complex spectrum for which PT symmetry is not spontaneously broken.4 pages, no figuresQuantum Physicstext