摘要
介绍测量、量子测量与经典测量的概念,阐述了三者之间的区别,分析量子力学中常用的三种测量:广义测量,正交投影测量及正算子值测量(POVM),论证它们的性质,简述了三种测量的适用范围和相互关系,即对大系统进行正交测量时,在子系统上实现的测量是广义测量,在子系统中实现的投影测量是一组正算子值测量(POVM),对孤立系统进行的测量是正交投影测量,广义测量等同于正交投影测量和酉演化的组合。
This paper firstly introduces the concepts and their distinction between measurement, quantum measurement and classical measurement, and then analyzes the characteristic of the general measurement, orthogonal projective measurement and POVM, and finally simply gives applicable conditions and correlations of those three measurements. Making orthogonal measurement in a system can gain the general measurement in its subsystem, and making projective measurement in a subsystem, can gain a group of POVM. Making measurement in an isolated system can get orthogonal projective measurement, while the general measurement is equivalent to the combination of orthogonal projective measurement and unitary evolution.
出处
《咸阳师范学院学报》
2008年第4期25-28,共4页
Journal of Xianyang Normal University
基金
咸阳师范学院科研基金项目(06XSYK279)
关键词
广义测量
正交投影测量
正算子值测量
the general measurement
orthogonal projective measurement
positive operator-valued measure
