CRC Press eBooks

Time Dependent Perturbation Theory

Asim Gangopadhyaya, Constantin Rasinariu

Published Jul 28, 2025• 0 citations

Abstract

In time-independent perturbation theory, we were interested in finding the eigenvalues and eigenstates of a system whose Hamiltonian could be written as the sum of a known Hamiltonian and another “small” term describing the perturbation. In time-dependent perturbation theory, the goal is different. We determine the time evolution operator of the perturbed system and use it to estimate the transition probabilities between two states of the unperturbed system.

DOI: 10.1201/9781003174967-11

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