贝尔不等式的量子违背及其实验检验——兼议2022年诺贝尔物理学奖  

Quantum violation of Bell’s inequality and its experimental test——on the Nobel Prize in Physics 2022

作　　者：崔廉相 许康 张芃[3] 孙昌璞 CUI Lian-Xiang;XU Kang;ZHANG Peng;SUN Chang-Pu(Beijing Computational Science Research Center,Beijing 100193,China;Graduate School of China Academy of Engineering Physics,Beijing 100193,China;Department of Physics,Renmin University of China,Beijing 100872,China)

机构地区：[1]北京计算科学研究中心,北京100193 [2]中国工程物理研究院研究生院,北京100193 [3]中国人民大学物理学系,北京100872

出　　处：《物理》2023年第1期1-17,共17页Physics

基　　金：国家自然科学基金基础中心项目(批准号:L1924037);国家自然科学基金委员会——中国科学院学科发展战略研究联合项目(批准号:XK2019SLC002)。

摘　　要：2022年诺贝尔物理学奖授予法国、美国和奥地利的三位科学家阿兰·阿斯佩、约翰·弗朗西斯·克劳泽和安东·塞林格,以表彰他们利用纠缠光子实验检验贝尔不等式以及在开拓量子信息科学方面做出的卓越贡献。贝尔不等式在量子力学基本问题和量子信息研究中都有着不可或缺的地位,它的违背直接揭示了量子力学的基本特征——量子非定域性。文章在讲清楚基本科学概念的基础上,简要介绍了贝尔不等式理论的建立及验证其违背的实验研究的科学历程。为了解决EPR佯谬,基于玻姆的定域隐变量理论,约翰·贝尔提出了关于纠缠态上的关联测量满足的基本不等式——贝尔不等式。他还发现,量子力学关于关联的计算结果违背贝尔不等式,可以在类空距离上展现出“鬼魅”的长程量子关联。这种长程关联看似有超光速的“超距作用”,但这只是人们明显或潜在地使用了“波包塌缩假设”。EPR文章明显地采用这个假设推断远方客体共存的物理实在要素,由此对量子力学完备性提出质疑。文章评述了阿斯佩、克劳泽和塞林格荣获诺贝尔物理学奖的关于贝尔不等式违背的判定性实验,介绍了华人物理学家在纠缠态和贝尔不等式研究方面的基础性贡献,包括早年吴健雄利用正负电子湮灭产生EPR光子的先驱性实验,李政道和杨振宁关于产生两个中性K介子K0—K0形成EPR态的建议,史砚华、欧泽宇、彭堃墀等利用非线性光学晶体,包括陈创天等人发现的非线性光学晶体,产生纠缠光子对的原创性工作。The Nobel Prize in Physics 2022 was awarded to Alain Aspect,John F.Clauser and Anton Zeilinger,for experiments with entangled photons,establishing the violation of Bell inequalities and pioneering quantum information science.Bell’s inequality plays an indispensable role in the foundations of quantum mechanics and quantum information;its violation directly reveals the nonlocal nature of quantum mechanics.Clarifying some basic concepts,this paper briefly introduces the establishment of Bell’s inequality and the relevant research on its experimental verification.In order to solve the EinsteinPodolsky-Rosen(EPR) paradox,John S.Bell proposed his inequality according to D.Bohm’s theory of localized hidden variables.He found that the results from quantum mechanics for such correlations violated the inequality and then displayed a "spooky" long-range quantum correlation even over space-like distances.This long-range correlation appears to have faster-than-light "action at a distance",which is simply due to the obvious or potential use of the "wave-packet collapse" postulate.The EPR paper explicitly used this assumption to infer the physical reality elements of distant objects,thus questioned the completeness of quantum mechanics.We review the groundbreaking experiments on the violation of Bell’s inequality conducted by Aspect,Clauser and Zeilinger,then furthermore recall the foundational contributions of Chinese physicists in creating entangled states and testing the violation of Bell’s inequality.In an early pioneering experiment,Chien-Shiung Wu et al utilized positron annihilation to generate EPR photons;TsungDao Lee and Chen-Ning Yang proposed that generating two neutral K-mesons K~0—K~0 to create EPR states;Yanhua Shih,Zhe-Yu Ou,Kun-Chi Peng,and others used various nonlinear optical crystals,including those discovered by Chuang-Tian Chen et al,to generate entangled photon pairs.

关 键 词：2022年诺贝尔物理学奖 贝尔不等式 EPR佯谬 量子纠缠 

分 类 号：O413-19[理学—理论物理]