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81.
To date there has been only one test for local reality which used fermions. Lamehi-Rachti and Mittig measured correlated protons with a recoil polarimeter at Saclay. We discuss this experiment and survey the published criticism. We then propose an experiment involving a 500 MeV electron beam on a 3He target. The two protons in the 3He nucleus originally have their spins anti-aligned. The spins of the ejected protons can be measured with a recoil polarimeter and the correlation function obtained, which will be a good test of Local Reality and Bell's inequality.  相似文献   
82.
设计了适合自由空间量子通讯实验的纠缠源. 纠缠光子对的单模光纤搜集率约为每秒20000对,水平竖直方向的纠缠对比度大于95%,正负45°方向的纠缠对比度大于90%. 在本地得到了大于100个标准偏差的Bell 不等式破缺. 满足20 km量级的自由空间量子通讯试验要求. 关键词: 纠缠光子对 位相匹配 收集效率 贝尔不等式  相似文献   
83.
A simplified scheme is proposed for the test of quantum nonlocality of the type described by Hardy [Phys.Rev.Left.71 (1993) 1665] .In the scheme two appropriately prepared atoms are simultaneously sent through a cavity and dispersively interact with the cavity field.Then state-selective measurements are performed on these atoms,which may reveal quantum nonlocality without using Bell inequality.We also propose a simple scheme for the generation of multi-atom entangled states.  相似文献   
84.
This paper investigates the thermal pairwise entanglement of a three-qubit Heisenberg XXZ chain in the presence of the Dzyaloshinski--Moriya (DM) anisotropic antisymmetric interaction and quantum teleportation when using the Heisenberg chain as a channel. The entanglement dependences on the DM interaction and temperature are given in detail. It obtains the relation between the concurrence and average fidelity, and shows that the same concurrence can lead different average fidelities. Moreover, it finds the thermally entangled states which do not violate the Bell inequalities, and can still be used for quantum teleportation.  相似文献   
85.
AS Majumdar  N Nayak 《Pramana》2001,56(2-3):161-167
We examine a local realist bound in the case of a one-atom micromaser. It is shown that such a bound is violated using a simplified treatment of the micromaser. We consider the effect of dissipation in a proposed experiment with the real micromaser. It is seen that the magnitude of violation of a Bell-type inequality depends significantly on the cavity parameters.  相似文献   
86.
《中国物理 B》2021,30(10):100503-100503
We investigate the synchronization problem between identical chaotic systems only when necessary measurement(output) and actuation(input) are needed to be implemented by the adaptive controllers. A sufficient condition is derived based on the Lyapunov stability theory and Schur complementary lemma. Moreover, the theoretic result is applied to the Rikitake system and the hyperchaotic Liu system to show its effectiveness and correctness. Numerical simulations are presented to verify the results.  相似文献   
87.
蒋文杰  邓东灵 《物理》2021,50(2):76-83
神经网络量子态是由人工神经网络所表示的量子态。得益于机器学习,尤其是深度学习近年来取得的突破性进展,神经网络量子态的研究得到了广泛的关注,成为当前的热点前沿方向。文章将介绍不同的神经网络量子态,其物理性质与典型应用场景,最新进展,以及面临的挑战。  相似文献   
88.
本文引入并研究一类新的广义集值强非线性拟变分不等式,讨论这类广义集值强非线性拟变分不等式解的存在性以及由算法所构造的迭代序列的收敛性.我们的结果改进和发展了Noor,Siddiqi和Ansari等人近期的一些主要结果.  相似文献   
89.
C. S. Unnikrishnan 《Pramana》2005,65(3):359-379
I discuss in detail the result that the Bell’s inequalities derived in the context of local hidden variable theories for discrete quantized observables can be satisfied only if a fundamental conservation law is violated on the average. This result shows that such theories are physically nonviable, and makes the demarcating criteria of the Bell’s inequalities redundant. I show that a unique correlation function can be derived from the validity of the conservation law alone and this coincides with the quantum mechanical correlation function. Thus, any theory with a different correlation function, like any local hidden variable theory, is incompatible with the fundamental conservation laws and space-time symmetries. The results are discussed in the context of two-particle singlet and triplet states, GHZ states, and two-particle double slit interferometry. Some observations on quantum entropy, entanglement, and nonlocality are also discussed.  相似文献   
90.
李桂芳  李会莹  杨成梧 《中国物理》2005,14(12):2379-2386
This paper deals with the robust passivity synthesis problem for a class of uncertain linear systems with time-varying delay in state and control input. The parameter uncertainties are norm-bounded and allowed to appear in all matrices of the model. The problem aims at designing an observer-based dynamic output-feedback controller that robustly stabilizes the uncertain systems and achieves the strict passivity of closed-loop systems for all admissible uncertainties. By converting the problem at hand into a class of strictly passive control problem for a parameterized system, the explicit solution is established and expressed in terms of a linear matrix inequality. A numerical example is provided to demonstrate the validity of the proposed approach.  相似文献   
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