Persistence of exponential decay for metastable quantum states at long times
Department of Physics, Dartmouth College - Hanover,
NH 03755, USA
Accepted: 12 December 2001
Quantum dynamics predicts that a metastable state should decay exponentially except at very early and very late times. We show through an exactly soluble model that if the decay products can interact weakly with their environment, then the exponential decay regime is prolonged to later times, while the exponential decay constant itself remains essentially unaffected. As the number of environmental degrees of freedom is increased, the asymptotic late-time decay follows higher powers of 1/t and the exponential decay regime is extended without limit.
PACS: 03.65.Ta – Foundations of quantum mechanics; measurement theory / 03.65.Nk – Scattering theory / 03.65.Xp – Tunneling, traversal time, quantum Zeno dynamics
© EDP Sciences, 2002