Classical Correlations vs Quantum Correlations—Similarities, Differences, Opportunities

Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schrödinger’s responses shortly after. In this paper, we contrast classical with quantum correlations. We find that classical correlations are weaker than quantum correlations in the CHSH framework. With respect to correlation matrices, the trace of classical correlation matrices is dissimilar to quantum density matrices. However, the off-diagonal terms have equivalent interpretations. We contrast classical dynamic (i.e., time evolving) stochastic correlation with dynamic quantum density matrices and find that the off-diagonal elements, while different in nature, have similar interpretations. So far, due to the laws of quantum physics, no classical correlations are applied to the quantum spectrum. However, conversely, quantum correlations are applied in classical environments such as quantum computing, cryptography, metrology, teleportation, medical imaging, laser technology, the quantum Internet and more.

Quantum and classical correlations for a two-qubit X structure density matrix

We derive explicit expressions for quantum discord and classical correlation for an X structure density matrix. Based on the characteristics of the expressions, the quantum discord and the classical correlation are easily obtained and compared under different initial conditions using a novel analytical method. We explain the relationships among quantum discord, classical correlation, and entanglement, and further find that the quantum discord is not always larger than the entanglement measured by concurrence in a general two-qubit X state. The new method, which is different from previous approaches, has certain guiding significance for analysing quantum discord and classical correlation of a two-qubit X state, such as a mixed state.

Effects of Atomic Coherence and Injected Classical Field on Chaotic Dynamics of Non-degenerate Cascade Two-Photon Lasers

Based on the cascade two-photon laser dynamic equation derived with the technique of quantum Langevin operators with the considerations of coherently prepared three-level atoms and the classical field injected into the cavity, we numerically study the effects of atomic coherence and classical field on the chaotic dynamics of a two-photon laser. Lyapunov exponent and bifurcation diagram calculations show that the Lorenz chaos and hyperchaos can be induced or inhibited by the atomic coherence and the classical field via crisis or Hopf bifurcations.

Control of sudden transition between classical and quantum correlations of two strongly driven atoms in dissipative cavities

We investigate analytically the dynamics of classical and quantum correlations between two strongly driven atoms, each of which is trapped inside a dissipative cavity. It is found that there exists a finite time interval during which the quantum discord initially prepared in the X-type states is not destroyed by the decay of the cavities. The sudden transition between classical correlation and quantum discord is sensitive to the initial-state parameter, the cavity decay rate, and the cavity mode-driving field detuning. Interestingly, we show that the transition time can be prolonged significantly by increasing the degree of the detuning.

A method for stochastic seismic response analysis of non-classically damped structures

A method to calculate the stationary random response of a non-classically damped structure is proposed that features clearly-defined physical meaning and simple expression. The method is developed in the frequency domain. The expression of the proposed method consists of three terms, i.e., modal velocity response, modal displacement response, and coupled (between modal velocity and modal displacement response). Numerical results from the parametric study and three example structures reveal that the modal velocity response term and the coupled term are important to structural response estimates only for a dynamic system with a tuned mass damper. In typical cases, the modal displacement term can provide response estimates with satisfactory accuracy by itself, so that the modal velocity term and coupled term may be ignored without loss of accuracy. This is used to simplify the response computation of non-classically damped structures. For the white noise excitation, three modal correlation coefficients in closed form are derived. To consider the modal velocity response term and the coupled term, a simplified approximation based on white noise excitation is developed for the case when the modal velocity response is important to the structural responses. Numerical results show that the approximate expression based on white noise excitation can provide structural responses with satisfactory accuracy.

Thoughts on Coronavirus Disease 2019 Based on JingFang Medicine (Classical Chinese Formula) Solutions for COVID-19

This article aims to provide some thoughts on the prevention and treatment of Coronaviras Disease 2019(COVTD-19)from the perspective of JingFang Medicine(Classical Chinese Formula).It is believed that the vague theoretical understanding of COVTD-19 in Traditional Chinese Medicine does not hinder the precise treatment of the disease by following the rale of“With this Zheng,prescribe this Fang.”According to the principle of“Fang-Zheng Correlation”and the knowledge gained from the thousands of years of experience in treating febrile diseases,Xiao Chai Hu Decoction(小柴胡汤)and its modifications are recommended with the emphasis on individualized treatment.As another form of practicing“Fang-Zheng Correlation,”generalized group treatment should also be paid attention to.Giving considerations to(ire historical medical data,Jing Fang Bai Du Powder(荆防败毒散)and Shi Shen Decoction(十神汤)are reconunended for group prevention treatment.Assisting the Zheng(Upright)Qi and using tonic formulas are two entirely different concepts.According to the principle of“Fang-Zheng Correlation,”tonics abuse should be avoided in the prevention of COVID-19,and the using of Huang Qi(黄芪Radix Astragali seu Hedysari)should also be very carefully done.

Thoughts on Coronavirus Disease 2019 Based on JingFang Medicine(Classical Chinese Formula)Solutions for COVID‑19

This article aims to provide some thoughts on the prevention and treatment of Coronavirus Disease 2019(COVID‑19)from the perspective of JingFang Medicine(Classical Chinese Formula).It is believed that the vague theoretical understanding of COVID‑19 in Traditional Chinese Medicine does not hinder the precise treatment of the disease by following the rule of“With this Zheng,prescribe this Fang.”According to the principle of“Fang‑Zheng Correlation”and the knowledge gained from the thousands of years of experience in treating febrile diseases,Xiao Chai Hu Decoction(小柴胡汤)and its modifications are recommended with the emphasis on individualized treatment.As another form of practicing“Fang‑Zheng Correlation,”generalized group treatment should also be paid attention to.Giving considerations to the historical medical data,Jing Fang Bai Du Powder(荆防败毒散)and Shi Shen Decoction(十神汤)are recommended for group prevention treatment.Assisting the Zheng(Upright)Qi and using tonic formulas are two entirely different concepts.According to the principle of“Fang‑Zheng Correlation,”tonics abuse should be avoided in the prevention of COVID‑19,and the using of Huang Qi(黄芪Radix Astragali seu Hedysari)should also be very carefully done.

Quasi-classical trajectory approach to the O(~1D)+HBr→OH+Br reaction stereo-dynamics on X^1A'potential energy surface

The vector properties of reaction O（1D）＋HBr→OH＋Br on the potential energy surface （PES） of X1A＇ ground singlet state are studied by using the quasi-classical trajectory （QCT） theory. The polarization-dependent differential cross sections （PDDCSs）, the average rotational alignment factor （P 2 （j＇- k）〉, as well as the distributions reflecting vector correlations are also computed. The analysis of the results shows that the alignment and the orientation distribution of the rotation angular momentum vector of product molecule OH is influenced by both the effect of heavy-light heavy （HLH） type mass combination and the deep well of PES.

猪瘟病毒中和抗体与E2蛋白抗体相关性分析

旨在探索猪瘟病毒中和抗体与E2蛋白抗体的关系,本研究对289份猪血清进行中和抗体效价和E2抗体测定,比较分析二者的相关性;同时从中选取15份血清,测定血清对不同猪瘟病毒流行野毒株的中和效价。结果表明,从整体上说E2抗体水平与中和效价呈正相关。当群体中所有个体E2抗体阻断率均大于60%时,才能保证群体70%以上免疫猪的中和抗体达到保护标准。本研究的结果有助于基层兽医工作者更好地评估临床中猪瘟疫苗的免疫保护状况,降低猪瘟疫情发生风险。

基于“五脏相关”理论辨治儿童变应性鼻炎

“五脏相关”理论对中医长期临床实践进行总结,以系统关联视角多维阐释人体各生理病理现象,指导疾病之诊断与防治。基于“五脏相关”理论结合小儿五脏不足、有余之生理特点辨治儿童变应性鼻炎,明晰其病位不离鼻窍,病机不离五脏;论治时调理脏腑,以脏调窍,在辨因审机的基础上,注重调肺、运脾、益肾、清心、疏肝,恢脏腑之安和,复鼻窍之通利。

多体非完全经典态的基于Affinity的关联测度

在量子信息理论中,量子关联是一种极其重要的物理资源。文章首先定义了多体非完全经典态基于Affinity的一种量子关联测度,它可以量化多体非完全经典态的关联程度;接下来证明了该关联测度满足量子关联度的一些必要物理性质,包括非负性、局部酉操作下的不变性、局部量子操作下的单调性、凸性以及连续性。

二态量子系统准确布居动力学的一类新型相空间表示及其与三角窗函数的关系

二态系统是最简单的且无经典对应的量子系统,对二态系统的同构表示的认识和研究能启发研究人员对其动力学与统计行为的更深刻理解.本文使用在[J.Chem.Phys.145,204105(2016);J.Chem.Phys.151,024105(2019);J.Phys.Chem.Lett.12,2496(2021)]等文章中发展的约束相空间严格理论、非协变相空间函数、含时权重函数与含时归一化因子来构建一类新型量子相空间表示.这类同构表示可以导出二态量子系统布居动力学的准确结果.约束相空间上的轨迹运动方程同构于含时薛定谔方程.每条相空间轨迹对于布居动力学所对应积分表达式的贡献严格半正定。进一步证明了在[J.Chem.Phys.145,144108(2016)]这篇文章中根据经验提出的三角窗函数方法在本质上可以对应于本文的这类新型相空间表示的一个特殊情况,因此同样是二态量子系统准确布居动力学的同构表示.

Correlation dynamics of two-parameter qubit-qutrit states under decoherence

We investigate the dynamics of correlations for two-parameter qubit--qutrit states under various local decoherence channels including depalising, phase-flip, bit- and trit-flip, bit- and trit-phase-flip, and depolarizing channels. We find that, under certain conditions, the classical： correlations may not be affected by the noise or decay monotonically. The quantum correlations measured by measurement-induced disturbance （MID） show three types of dynamical behaviors： （i） monotonic ＇decay to zero, （ii） monotOniC decay to a nonzero steady value, （iii） increase from zero and then decrease to zero in a monotonic way. Consequently, we find that, differing from the dynamics of entanglement, the present classical and quantum correlations do not reveal sudden death behavior.

A Violation of the Special Theory of Relativity Demonstrated Using the Correlation between Two Pair-Generated Photons

When Einstein developed the special theory of relativity (STR), he assumed the principle of relativity, i.e. that all inertial frames are equivalent. Einstein thought it was impossible to differentiate inertial frames into classically stationary frames where light propagates isotropically, and classically moving frames where light propagates anisotropically. However, the author has previously pointed out that classically moving frames have a velocity vector attached, and presented a thought experiment for determining the size of that velocity vector. The author has already shown a violation of the STR, but this paper presents a violation of the STR using different reasoning. More specifically, this paper searches for a coordinate system where light propagates anisotropically. This is done by using the correlation of two photons pair-generated from a photon pair generator. If the existence of such a coordinate system can be ascertained, it will constitute a violation of the STR.

What Does Monogamy in Higher Powers of a Correlation Measure Mean?

We examine here the proposition that all multiparty quantum states can be made monogamous by considering positive integral powers of any quantum correlation measure. With Rajagopal-Rendell quantum deficit as the measure of quantum correlations for symmetric 3-qubit pure states, we illustrate that monogamy inequality is satisfied for higher powers of quantum deficit. We discuss the drawbacks of this inequality in quantification of correlations in the state. We also prove a monogamy inequality in higher powers of classical mutual information and bring out the fact that such inequality needs not necessarily imply restricted shareability of correlations. We thus disprove the utility of higher powers of any correlation measure in establishing monogamous nature in multiparty quantum states.

LDPC陪集码的可区分性及其在语义通信中的应用

经典通信的目标是可靠传输信息符号,其很少利用语义信息。提出了一种在低时延的情况下,利用数据信息之间的语义关联性来获得经典译码性能增益的传输方案。基于低密度奇偶校验陪集码的可区分性,所提方案利用便车码来传输语义信息关联标识。若接收端判断信息存在语义关联,则根据预设的语义关联度进行迭代译码。仿真结果表明,语义信息能够为经典信道编码带来增益。

基于“和法”治疗焦虑相关性失眠经验探析

焦虑相关性失眠是临床常见疾病,该病的根本病机可概括为阴阳失和,包括少阳气机不畅、心胃脏腑不和、厥阴寒热失衡。戴淑青教授基于“和法”理论,通过调理少阳气机升降、厥阴枢机开阖、心和脾胃升降治疗该病。总结戴淑青教授运用中医经典名方治疗焦虑相关性失眠的临证经验,并附医案三则以资佐证,以期更好改善该类患者的睡眠质量,缓解其抑郁及焦虑症状。

基于可拓分析法的电力变压器本体绝缘状态评估

实现电力变压器状态的准确评估不仅是施行状态检修的核心与基础,同时也是发展智能电网的需要。针对电力变压器故障机理错综复杂和本体绝缘状态具有不确定性,因而难以客观有效评估的问题,以220kV油浸式电力变压器为研究对象,提出了基于物元可拓分析的电力变压器本体绝缘状态评估策略。在对其本体状态评估物元分析的基础上,构造了各评估指标的关联函数,指标关联函数值在正常运行的量变范围内为正,当量变突变到质变时关联函数值取负;通过研究关联函数值与变压器状态的对应关系,探讨了变压器的状态评估策略。实例分析并与其他评估方法比较证明:该方法行之有效,基于物元可拓分析的电力变压器状态评估策略可以为实施状态检修提供参考。

O(3P)＋H2→OH＋H反应的立体动力学研究

利用BMSl势能面[Brandao等，J．Chem．Phys．121，8861（2004）]，选取碰撞能为34．6kcal／mol，用准经典轨线方法研究了O（3P）＋H2反应的立体动力学性质．计算并讨论了k与j′的夹角的分布关系P（θr）以及描述k-k′-j′三者关系的二面角分布P（φr）．（k为反应物速度方向，k′为产物的速度方向，j′为产物的角动量方向）P（研）的峰值在90°附近并且关于90°呈对称性分布，这表明产物角动量的方向与初速度的方向垂直．二面角分布P（研）关于散射平面呈反对称性分布，这一结果表明产物的角动量具有强烈的极化效应．另外，我们还研究了振动激发对产物角动量的影响，结果表明产物的矢量性质对反应物的初始振动态非常敏感．

肝脾相关理论的经典溯源

肝脾相关是中医学五脏相关理论的重要组成部分,其理论渊源来源于《内经》《难经》,应用于《伤寒论》。文章主要从《内经》《难经》和《伤寒论》三部经典著作中溯源肝脾相关理论,从生理、病理及方证运用方面探讨肝脾相关的学术源流,为肝脾相关理论指导临床治疗提供经典理论依据。