Central European Journal of Physics

, Volume 10, Issue 2, pp 282–319

Time-delay of classical and quantum scattering processes: a conceptual overview and a general definition

Review Article

DOI: 10.2478/s11534-011-0105-5

Cite this article as:
Sassoli de Bianchi, M. centr.eur.j.phys. (2012) 10: 282. doi:10.2478/s11534-011-0105-5


We present a step by step introduction to the notion of time-delay in classical and quantum mechanics, with the aim of clarifying its foundation at a conceptual level. In doing so, we motivate the introduction of the concepts of “fuzzy” and “free-flight” sojourn times that we use to provide the most general possible definition for the quantum time-delay, valid for simple and multichannel scattering systems, with or without conditions on the observation of the scattering particle, and for incoming wave packets whose energy can be smeared out or sharply peaked (fixed energy). We conclude our conceptual analysis by presenting what we think is the right interpretation of the concepts of sojourn and delay times in quantum mechanics, explaining why, in ultimate analysis, they should not be called “times.”


time-delay sojourn time scattering theory time-dependent potentials non-spatiality 

Copyright information

© © Versita Warsaw and Springer-Verlag Wien 2012

Authors and Affiliations

  1. 1.Laboratorio di Autoricerca di BaseCaronaSwitzerland

Personalised recommendations