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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 {2. University, beijing 100875,{4. 2. Institute of Applied physics and Computational Mathematics, beijing 100080,{4. department of Mathematics Beijing Normal University Beijing China Institute of Applied physics and Computational Mathematics Beijing 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.

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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Science china(physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao department of physics, Institute of Theoretical physics, beijing {4. University, beijing 100875, china department of physics Institute of Theoretical Physics Beijing Normal University Beijing China

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2.2.to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.4.) by OHD only and (Ωm0, n) = (0.2., 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of physics,{2. University of Petroleum, Dongying 2.7061,{2. 2.department of physics, beijing normal University, beijing 100875,{2. department of physics China University of Petroleum Dongying China department of physics Beijing Normal University Beijing China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science china(physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, department of physics, Tsinghua University, {2. 100084. china Center for Quantum Information, Tsinghua University, {2. 100084. china department of Materials Science and Engineering, {2. normal University, beijing 100875, china Testing and Analytical Center, {2. normal University, beijing 100875, china department of physics, {2. normal University, beijing 100875, china Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China Center for Quantum Information Tsinghua University Beijing 100084 China department of Materials Science and Engineering Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China department of physics Beijing Normal University Beijing 100875 China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(department of physics, {2. normal University,{4., china)Xiaobo WEI(department of physics, Liuzhou College of Education, Liuzhou 54.005, china)Zhaodou CHEN Jun CAI and Benkun MA(department of physics, {2. normal University, department of physics Beijing Normal University Beijing 100875 China department of physics Liuzhou College of Education Liuzhou 545005 China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li Chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing normal University,{2., china 2. {4. department, beijing normal University,{2., china 3. china Institute of Atomic Energy, beijing 102.4}3, china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China physics department Beijing Normal University Beijing China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.0}Cm(2.Mg,4.)2.0Hs, 2.0}Pu(30Si,4.)2.0Hs, 2.8U(36S,4.)2.0Hs and 2.6Ra(4.Ca,4.)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(4.Ca,4.)2.0Hs and 2.8U(36S,4.)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Constraints on Cardassian universe from Gamma ray bursts

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1720-1725页

作者： WANG TaiShan1 & LIANG Nan2.1 department of physics & Center for Astrophysics,Tsinghua University,beijing 100084.{4. 2.department of Astronomy,beijing normal University,beijing 100875,{4. department of physics & Center for Astrophysics Tsinghua University Beijing China department of Astronomy Beijing Normal University Beijing China

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 4. gamma-ray bursts(GRBs) data calibrated with the method that can avoid the circularity *** results show that GRBs can be an optional observation to constrain the Cardassian *** the GRBs data with the newly de-rived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey(SDSS),and the position of the first acoustic peak of the Cosmic Microwave Background radiation(CMB) from Wilkinson Microwave Anisotropy Probe(WMAP),we find Ωm0=0.2.+0.02.0.02.n=0.06+0.07-0.08(1σ) for the original Cardassian model,and Ωm0=0.2.+0.2.-0.02.n=-0.09+0.2.-1.91,β=0.82.2.10-0.62.1σ) for the modified polytropic Cardassian model.

关键词： Cardassian Gamma ray burst Cosmic Microwave Background baryonic acoustic oscillation

Lookback time as a test for f(R) gravity in the Palatini approach

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Research in Astronomy and Astrophysics 2011年第11期11卷 1257-1265页

作者： Zhong-Xu Zhai and Wen-Biao Liu department of physics, Institute of Theoretical physics, beijing {4. University, beijing 100875, china department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

We use the recently released data of lookback time (LT)-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f (R) gravity in the Palatini formalism by considering the f (R) form of type (a) f (R) = R β/Rn and (b) f (R) = R + α ln R β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters (Ωm0, n) for (a) and (Ωm0, α) for (b). We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关键词： cosmology cosmic microwave background

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher College, Daqing 163712. china 2. department of {2. , beijing {4. University, beijing 100875, china Scientific and Technological Office Daqing Teacher College Daqing China department of physics Beijing Normal University Beijing China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.