2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/186931We use fits to recent published CPLEAR data on neutral kaon decays to $π^+π^-$ and $πeν$ to constrain the CPT--violation parameters appearing in a formulation of the neutral kaon system as an open quantum-mechanical system. The obtained upper limits of the CPT--violation parameters are approaching the range suggested by certain ideas concerning quantum gravity.9 pages of uuencoded postscript (includes 3 figures)High Energy Physics - ExperimentHigh Energy Physics - PhenomenologyHigh Energy Physics - Theorytext