# Particle decay in Gaussian wave-packet formalism revisited

@article{Ishikawa2018ParticleDI,
title={Particle decay in Gaussian wave-packet formalism revisited},
author={Kenzo Ishikawa and Kin-ya Oda},
journal={Progress of Theoretical and Experimental Physics},
year={2018}
}
• Published 12 September 2018
• Physics
• Progress of Theoretical and Experimental Physics
We derive the Fermi's golden rule in the Gaussian wave-packet formalism of quantum field theory, proposed by Ishikawa, Shimomura, and Tobita, for the particle decay within a finite time interval. We present a systematic procedure to separate the bulk contribution from those of time boundaries, while manifestly maintaining the unitarity of the $S$-matrix unlike the proposal by Stueckelberg in 1951. We also revisit the suggested deviation from the golden rule and clarify that it indeed…
5 Citations

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