arXiv 0803.15612008-03-11quant-ph

Short Time Dynamics of Scalar Products in Hilbert Space

Adélcio C. Oliveira

备注：: 24 pages, 12 figures

英文摘要：

We use the semiclassical method proposed in \cite{Adelcio2003} to study scalar products such as the overlap, Husimi functions and fidelity decay. Scars of classical periodic orbits arise naturally in this pertubative expansion. We also derive analytically a well known numerical result that fidelity has a quadratic decay for short times. We study the overlap in the chaotic regime and integrable for some simple systems.

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