A pedagogical approach to the Magnus expansion

作者:Blanes S*; Casas F; Oteo J A; Ros J
来源:European Journal of Physics, 2010, 31(4): 907-918.
DOI:10.1088/0143-0807/31/4/020

摘要

Time-dependent perturbation theory as a tool to compute approximate solutions of the Schrodinger equation does not preserve unitarity. Here we present, in a simple way, how the Magnus expansion (also known as exponential perturbation theory) provides such unitary approximate solutions. The purpose is to illustrate the importance and consequences of such a property. We suggest that the Magnus expansion may be introduced to students in advanced courses of quantum mechanics.

  • 出版日期2010-7