Nonlocality and Multipartite Entanglement in Asymptotically Flat Space-Times  

作　　者：Shahpoor Moradi Firouz Amiri 

机构地区：[1]Department of Physics, Razi University, Kermanshah, Iran [2]Department of Physics, Khorram Abad Branch, Islamic Azad University, Iran

出　　处：《Communications in Theoretical Physics》2016年第1期17-22,共6页理论物理通讯（英文版）

基　　金：Islamic Azad University,Khorram Branch,for Financial support

摘　　要：We study the Bell's inequality and multipartite entanglement generation for initially maximally entangled states of free Dirac field in a non inertial frame and asymptotically flat Robertson–Walker space-time.For two qubit case,we show that the Bell's inequality always is violated as measured by the accelerated observers which are in the causally connected regions.On the other hand,for those observers in the causally disconnected regions inequality is not violated for any values of acceleration.The generated three qubit state from two qubit state due to acceleration of one parties has a zero 3-tangle.For a three qubit state,the inequality violated for measurements done by both causally connected and disconnected observers.Initially GHZ state with non zero 3-tangle,in accelerated frame,transformed to a four qubit state with vanishing 4-tangle value.On the other hand,for a W-state with zero 3-tangle,in non inertial frame,transformed to a four qubit state with a non-zero 4-tangle acceleration dependent.In an expanding space-time with asymptotically flat regions,for an initially maximally entangled state,the maximum value of violation of Bell's inequality in the far past decreased in the far future due to cosmological particle creation.For some initially maximally entangled states,the generated four qubit state due to expansion of space-time,has non vanishing 4-tangle.

关 键 词：Bell＇s inequality multiparticle entanglement accelerated frames expanding space-time 

分 类 号：O413.1[理学—理论物理] O412.1[理学—物理]