2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/94365We point out that the quantum Zeno effect, i.e., inhibition of spontaneous decay by frequent measurements, is observable only in spectrally finite reservoirs, i.e., in cavities and waveguides, using a sequence of evolution-interrupting pulses or randomly-modulated CW fields. By contrast, such measurements can only accelerate decay in free space.8 pages, 5 figuresQuantum Physicstext