Deviations from exponential law and Van Hove ’ s “ λ 2 t ” limit
نویسندگان
چکیده
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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تاریخ انتشار 1999