arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1207.6909quant-phcond-mat.stat-mech
收藏

复杂动力系统的Wigner分布函数:路径积分方法

Wigner distribution functions for complex dynamical systems: a path integral approach

Dries Sels, Fons Brosens, Wim Magnus

摘要:

从量子力学的费曼拉格朗日描述出发,提出了一种明确构造单个系统Wigner分布函数传播子的方法。对于一般的二次拉格朗日,只有经典的相空间轨迹被发现有助于传播。受Feynman和Vernon的影响泛函理论的启发,我们将该方法扩展到计算感兴趣的系统与外部系统耦合的约化Wigner函数的传播子。当外系统由一组独立谐振子组成时,得到了显式表达式。作为一个例子,我们计算与Caldeira-Legett模型相关的约化Wigner函数的传播子。

英文摘要:

Starting from Feynman's Lagrangian description of quantum mechanics, we propose a method to construct explicitly the propagator for the Wigner distribution function of a single system. For general quadratic Lagrangians, only the classical phase space trajectory is found to contribute to the propagator. Inspired by Feynman's and Vernon's influence functional theory we extend the method to calculate the propagator for the reduced Wigner function of a system of interest coupled to an external system. Explicit expressions are obtained when the external system consists of a set of independent harmonic oscillators. As an example we calculate the propagator for the reduced Wigner function associated with the Caldeira-Legett model.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑