Deviations from exponential law and Van Hove's "λ^2 t" limit

P. Facchi; S. Pascazio

doi:10.1016/s0378-4371(99)00209-5

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arXiv · quant-ph/9904020

Deviations from exponential law and Van Hove's "λ^2 t" limit

P. Facchi·S. Pascazio

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Abstract

The deviations from a purely exponential behavior in a decay process are analyzed in relation to Van Hove's "λ^2 t" limiting procedure. Our attention is focused on the effects that arise when the coupling constant is small but nonvanishing. We first consider a simple model (two-level atom in interaction with the electromagnetic field), then gradually extend our analysis to a more general framework. We estimate all deviations from exponential behavior at leading orders in the coupling constant.

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P. Facchi, S. Pascazio. 1999-04-06. Deviations from exponential law and Van Hove's "λ^2 t" limit. https://doi.org/10.1016/s0378-4371(99)00209-5

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