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Tunneling Through Black Rings

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Communications in Theoretical physics 2007年第5期47卷 835-842页

作者： ZHAO Liu department of physics,nankai {2.,tianjin 300071,china department of physics Nankai University

Hawking radiation of black ring solutions to 5-dimensional Einstein-Maxwell-dilaton theory is analyzedby use of the Parikh-Wilczek tunneling *** get the correct tunneling amplitude and emission rate,we adoptand develop the Angheben-Nadalini-Vanzo-Zerbini covariant approach to cover the effects of rotation and electronicdischarge all at once,and the effect of back reaction is also taken into *** constitutes a unified approach tothe tunneling *** the first law of thermodynamics for black rings holds,the emission rate is proportionalto the exponential of the change of Bekenstein-Hawking *** calculation for black ring temperatures agreesexactly with the results obtained via the classical surface gravity method and the quasi-local formalism.

关键词： black ring radiation tunneling method

Study of D^0-D^0 mixing at a giga-Z linear collider

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1953-1956页

作者： LI HaiBo 1 & YANG MaoZhi 2.1 institute of High Energy physics,P.O.Box 918,{2. 100049,china 2.School of physics,nankai university,tianjin 300071,china institute of High Energy physics Beijing China School of physics Nankai University Tianjin China

The possibility of studying D 0-D 0 mixing at a giga-Z linear collider "Z factory" where 10 9 hadronic Z 0 decays can be accumulated is *** discuss the sensitivity for the measurements of neutral D mixing *** results are compared to those attainable at B *** find that the typical decay length of the neutral D mesons at Z factory is about 10 times larger than that at B *** addition,the resolution of the vertex detector of a giga-Z factory is 2.3 times better than that of B *** proper time resolution at Z factory is about 2.-30 times better than that at B *** the determination of the mixing parameters at a giga-Z factory is more precise.

关键词： Z factory D0 mesons mixing B factory

Discussion of Some Problems About Nonlinear Time Series Prediction Using v-Support Vector Machine

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Communications in Theoretical physics 2007年第7期48卷 117-124页

作者： GAO Cheng-Feng CHEN Tian-Lun NAN Tian-Shi department of physics,nankai {2.,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

Some problems in using v-support vector machine(v-SVM)for the prediction of nonlinear time series *** problems include selection of various net parameters,which affect the performance of prediction,mixtureof kernels,and decomposition cooperation linear programming v-SVM regression,which result in improvements of *** simulations in the prediction of nonlinear time series produced by Mackey-Glass equation andLorenz equation provide some improved results.

关键词： v-SVM nonlinear time series prediction

Nonlinear Dynamical Behavior in BS Evolution Model Based on Small-World Network Added with Nonlinear Preference

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Communications in Theoretical physics 2007年第7期48卷 137-142页

作者： ZHANG Ying-Yue YANG Qiu-Ying CHEN Tian-Lun department of physics,nankai {2.,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

We introduce a modified small-world network adding new links with nonlinearly preferential connectioninstead of adding randomly,then we apply Bak-Sneppen(BS)evolution model on this *** study severalimportant structural properties of our network such as the distribution of link-degree,the maximum link-degree,and thegth of the shortest *** further argue several dynamical characteristics of the model such as the important criticalvalue f_c,the f_0 avalanche,and the mutating condition,and find that those characteristics show panticular behaviors.

关键词： power-law behavior small-world network evolution model nonlinear preference

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science china Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2.1. department of Mathematics, beijing Normal {2., beijing 100875, china 2. institute of Applied physics and Computational Mathematics, beijing 100080, china 1. department of Mathematics Beijing Normal University Beijing 100875 China 2. institute of Applied physics and Computational Mathematics Beijing 100080 China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2.and CHEN Nanxian1(1. department of physics, Tsinghua university, {2. 100084, china 2. department of physics, Peking university, {2. 100871, china) department of physics Tsinghua University Beijing 100084 China department of physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

Pairwise entanglement and local polarization of Heisenberg model

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2. ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2.1 department of Applied Mathematics and physics, Xi’an {2. of Post and Telecommunications, Xi’an 710061, china 2.beijing National Laboratory for Condensed Matter physics, {2. of physics, Chinese Academy of Sciences, beijing 100080, china 3 {2. of Modern physics, Northwest {12., Xi’an 710069, china 4 department of physics, Ningbo {12., Ningbo 3152.1, china department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an 710061 China beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China institute of Modern physics Northwest University Xi’an 710069 China department of physics Ningbo University Ningbo 315211 China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2.for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412.(for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

Direct CP violation in hadronic B decays

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3 1. department of physics, Lishui university, Lishui 32.000,{2. 2. department of physics, Shanghai Jiaotong university, Shanghai 2.0030, china 3. institute of High Energy physics, beijing 100049,{2. department of physics Lishui University Lishui 323000 China department of physics Shanghai Jiaotong University Shanghai 200030 China institute of High Energy physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

The information entropy of a static dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou institute of Theoretical physics, Binzhou {2., Binzhou 2.6600, china department of physics, beijing Normal {2., beijing 100875, china 1. institute of Theoretical physics Binzhou University Binzhou 256600 China 2. department of physics Beijing Normal University Beijing 100875 China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity