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半单Malcev代数上不变双线性型的自对称性
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作者 刘淑俊 《邯郸职业技术学院学报》 2002年第4期64-65,共2页
介绍Malcev代数的定义 ,并在特征为零的数域上讨论Malcev代数的理想 ,单性 ,半单性 ;利用不变性及Jacobian证明单Malcev代数上不变双线性型的自对称性 。
关键词 Malcev代数 不变双线性型 自对称性 单李代数
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Exact Solutions of a Generalized Multi-Fractional Nonlinear Diffusion Equation in Radical Symmetry 被引量:9
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作者 LIU Yan-Qin MA Jun-Hai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期857-861,共5页
This paper is devoted to investigating exact solutions of a generalized fractional nonlinear anomalousdiffusion equation in radical symmetry.The presence of external force and absorption is also considered.We firstinv... This paper is devoted to investigating exact solutions of a generalized fractional nonlinear anomalousdiffusion equation in radical symmetry.The presence of external force and absorption is also considered.We firstinvestigate the nonlinear anomalous diffusion equations with one-fractional derivative and then multi-fractional ones.Inboth situations,we obtain the corresponding exact solutions,and the solutions found here can have a compact behavioror a long tailed behavior. 展开更多
关键词 fractional derivative multi-fractional diffusion equation anomalous diffusion equation
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A Coupled Hybrid Lattice: Its Related Continuous Equation and Symmetries 被引量:1
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作者 刘萍 付培凯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期5-10,共6页
The hybrid lattice, known as a discrete Korteweg-de Vries (KdV) equation, is found to be a discrete modified Korteweg-de Vries (mKdV) equation in this paper. The coupled hybrid lattice, which is pointed to be a discre... The hybrid lattice, known as a discrete Korteweg-de Vries (KdV) equation, is found to be a discrete modified Korteweg-de Vries (mKdV) equation in this paper. The coupled hybrid lattice, which is pointed to be a discrete coupled KdV system, is also found to be discrete form of a coupled mKdV systems. Delayed differential reduction system and pure difference systems are derived from the coupled hybrid system by means of the symmetry reduction approach. Cnoidal wave, positon and negaton solutions for the coupled hybrid system are proposed. 展开更多
关键词 coupled hybrid lattice SYMMETRIES discrete KdV equation
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Two New Multi-component BKP Hierarchies 被引量:1
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作者 WU Hong-Xia LIU Xiao-Jun ZENG Yun-Bo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期193-199,共7页
We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with ... We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with self-consistent sources whose Lax representations are presented. The two mcBKP hierarchies both admit reductions to the k-constrained BKP hierarchy and to integrable (1+1)-dimensional hierarchy with self-consistent sources, which include two types of SK equation with self-consistent sources and of hi-directional SK equations with self-consistent 展开更多
关键词 multi-component BKP hierarchy BKP equation with self-consistent sources κ-constrained BKPhierarchy n-reduction of mcBKP Lax representation
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INSTABILITY OF SYMMETRIC TYPHOON CIRCULATION AND ADAPTIVE OBSERVATION 被引量:1
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作者 高守亭 周菲凡 刘黎平 《Journal of Tropical Meteorology》 SCIE 2009年第2期162-166,共5页
This study presents a new way to identify the sensitive areas,which are determined by invoking the negative anomalies of moist potential vorticity (MPV) for typhoon adaptive observations. It is found that the areas of... This study presents a new way to identify the sensitive areas,which are determined by invoking the negative anomalies of moist potential vorticity (MPV) for typhoon adaptive observations. It is found that the areas of negative MPV are the symmetric instability areas and can be taken as sensitive areas for typhoon adaptive observations. Three typhoons in 2008,Nuri,Fung-wong,and Fengshen,were simulated with the help of MM5 model. It is shown that these typhoons are well simulated in the first 12 hours. Based on these investigations,the calculations of MPV are carried out sequentially. The result shows that the negative maxima of MPV are always around the typhoon eyes for all the cases,which means that the sensitive areas are also near them all the time. 展开更多
关键词 TYPHOON moist potential vorticity (MPV) INSTABILITY sensitive areas
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Two-Photon Exchange Corrections to Single Spin Asymmetry of Neutron and 3He
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作者 CHEN Dian-Yong DONG Yu-Bing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期489-494,共6页
In a simple hadronie model, the two-photon exchange contributions to the single spin asymmetries for the nucleon and the 3He are estimated. The results show that the elastic contributions of two-photon exchange to the... In a simple hadronie model, the two-photon exchange contributions to the single spin asymmetries for the nucleon and the 3He are estimated. The results show that the elastic contributions of two-photon exchange to the single spin asymmetries for the nucleon are rather small while those for the 3He are relatively large. Besides the strong angular dependence, the two-photon contributions to the single transfer. spin asymmetry for the 3He are very sensitive to the momentum 展开更多
关键词 simple hadronic model two-photon exchange single spin asymmetry
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Solution of Dirac Equation with Killingbeck Potential by Using Wave Function Ansatz Method under Spin Symmetry Limit
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作者 M.Hamzavi A.A.Rajabi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期35-37,共3页
The Dirac equation is solved for Killingbeck potential. Under spin symmetry limit, the energy eigenvalues and the corresponding wave functions are obtained by using wave function ansatz method.
关键词 Dirac equation Killingbeck potential wave function ansatz method
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Distinct patterns of monthly Southern Annular Mode events
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作者 Minglin Zheng Xiuzhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第4期38-43,共6页
The Southern Annular Mode(SAM)is the leading mode of atmospheric variability in the mid–high latitudes of the Southern Hemisphere,representing large-scale variations in pressure and the polar front jet(PFJ).In SAM ev... The Southern Annular Mode(SAM)is the leading mode of atmospheric variability in the mid–high latitudes of the Southern Hemisphere,representing large-scale variations in pressure and the polar front jet(PFJ).In SAM events,the combination of the SAM and other modes may result in different atmospheric patterns.In this study,a neural-network-based cluster technique,the self-organizing map,was applied to extract the distinct patterns of SAM events on the monthly time scale based on geopotential height anomalies at 500 hPa.Four pairs of distinguishable patterns of positive and negative SAM events were identified,representing the diversity in spatial distribution,especially the zonal symmetry of the center of action at high latitudes—that is,symmetric patterns,split-center patterns,West Antarctica patterns,and a tripole pattern.Although the SAM is well known to be beltshaped,within the selected SAM events,the occurrence frequency of symmetric patterns is only 23.8%—less than that of West Antarctica patterns.Diverse PFJ variations were found in the symmetric and asymmetric patterns of SAM events.The more asymmetric the spatial distribution of the pressure anomaly,the more localized the adjusted zonal wind anomaly.The adjusted PFJ varied in meridional displacement and strength in different patterns of SAM events.In addition,the entrance and exit of the jet changed in most of the patterns,especially in the asymmetric patterns,which might result in different climate impacts of the SAM. 展开更多
关键词 Southern Annular Mode Self-organizing map Zonal asymmetry ANTARCTICA
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Invariant Functions, Symmetries and Primary Branch Solutions of First Order Autonomous Systems
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作者 Sen-Yue Lou Ruo-Xia Yao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第7期21-28,共8页
An invariant function (IF) is defined as a multiplier of a symmetry that means a symmetry multiplied by an IF is still a symmetry. Primary branch solutions of arbitrary first order scalar systems can be obtained by ... An invariant function (IF) is defined as a multiplier of a symmetry that means a symmetry multiplied by an IF is still a symmetry. Primary branch solutions of arbitrary first order scalar systems can be obtained by means of the IF and its related symmetry approach. Especially, one recursion operator and some sets of infinitely many high order symmetries are also explicitly given for arbitrary (l q-1)-dimensional first order autonomous systems. Because of the intrusion of the arbitrary function, various implicit special exact solutions can be found by fixing the arbitrary functions and selecting different seed solutions. 展开更多
关键词 invariant functions SYMMETRIES exact solutions invariant operators recursion Operators
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Spin and Pseudospin Symmetries of Dirac Equation and the Yukawa Potential as the Tensor Interaction
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作者 H.Hassanabadi E.Maghsoodi S.Zarrinkamar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第12期807-814,共8页
Considering of a tensor interaction in Dirac equation removes the degeneracy in spin and pseudospin doublets and consequently leads to results consistent with the experimental data. Here, instead of the commonly used ... Considering of a tensor interaction in Dirac equation removes the degeneracy in spin and pseudospin doublets and consequently leads to results consistent with the experimental data. Here, instead of the commonly used Coulomb or linear terms, we investigate a tensor interaction of Yukawa form. We obtain arbitrary state solutions of Dirac equation under vector, scalar and tensor Yukawa potentials via a physical approximation and the Nikiforov-Uvarov methodology. The solutions are discussed in detail. 展开更多
关键词 Dirac equation spin symmetry pseudospin symmetry tensor interaction Yukawa potential
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Exploitation of symmetry in periodic Self-Consistent-Field ab initio calculations: application to large three-dimensional compounds
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作者 DE LA PIERRE Marco ORLANDO Roberto +2 位作者 FERRABONE Matteo ZICOVICH-WILSON Claudio M. DOVESI Roberto 《Science China Chemistry》 SCIE EI CAS 2014年第10期1418-1426,共9页
Symmetry can dramatically reduce the computational cost (running time and memory allocation) of Self-Consistent-Field ab initio calculations for crystalline systems. Crucial for running time is use of symmetry in th... Symmetry can dramatically reduce the computational cost (running time and memory allocation) of Self-Consistent-Field ab initio calculations for crystalline systems. Crucial for running time is use of symmetry in the evaluation of one- and two-electron integrals, diagonalization of the Fock matrix at selected points in reciprocal space, reconstruction of the density matrix. As regards memory allocation, full square matrices (overlap, Fock and density) in the Atomic Orbital (AO) basis are avoided and a direct transformation from the packed AO to the SACO (Symmetry Adapted Crystalline Orbital) basis is per- formed, so that the largest matrix to be handled has the size of the largest sub-block in the latter basis. We here illustrate the effectiveness of this scheme, following recent advancements in the CRYSTAL code, concerning memory allocation and direct basis set transformation. Quantitative examples are given for large unit cell systems, such as zeolites (all-silica faujasite and silicalite MF1) and garnets (pyrope). It is shown that the full SCF of 3D systems containing up to 576 atoms and 11136 Atomic Orbitals in the cell can be run with a hybrid functional on a single core PC with 500 MB RAM in about 8 h. 展开更多
关键词 point symmetry Symmetry Adapted Crystalline Orbitals Fock matrix density matrix CPU time memory allocation quantum-mechanical calculations CRYSTAL code
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Quantifying Spontaneously Symmetry Breaking of Quantum Many-Body Systems
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作者 董国慧 房一楠 孙昌璞 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第10期405-411,共7页
Spontaneous symmetry breaking is related to the appearance of emergent phenomena, while a non-vanishing order parameter has been viewed as the sign of turning into such symmetry-breaking phase. We study the spontaneou... Spontaneous symmetry breaking is related to the appearance of emergent phenomena, while a non-vanishing order parameter has been viewed as the sign of turning into such symmetry-breaking phase. We study the spontaneous symmetry breaking in the conventional superconductor and Bose–Einstein condensation with a continuous measure of symmetry by showing that both the many-body systems can be mapped into the many spin model. We also formulate the underlying relation between the spontaneous symmetry breaking and the order parameter quantitatively. The degree of symmetry stays unity in the absence of the two emergent phenomena, while decreases exponentially at the appearance of the order parameter which indicates the inextricable relation between the spontaneous symmetry and the order parameter. 展开更多
关键词 spontaneous symmetry breaking Bose-Einstein condensation SUPERCONDUCTOR group theory
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(n+1)-Dimensional Gravity Duals to Quantum Criticalities with Spontaneous Symmetry Breaking
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作者 曾定方 赵凯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第10期458-464,共7页
We reexamine the charged AdS domain wall solution to the Einstein-Abelian-Higgs model proposed by Gubser et al. as holographic superconductors at quantum critical points and comment on their statement about the unique... We reexamine the charged AdS domain wall solution to the Einstein-Abelian-Higgs model proposed by Gubser et al. as holographic superconductors at quantum critical points and comment on their statement about the uniqueness of gravity solutions. We generalize their explorations from (3 + 1)-dimensions to arbitrary n -b 1Ds and find that the n +1≥5D charged AdS domain walls are unstable against electric perturbations. 展开更多
关键词 quantum critical superconductors holographic dualities Einstein-Abelian-Higgs model
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Detection of topological symmetry in the one-dimensional Afeck-Kennedy-Lieb-Tasaki model of integer spin with ultracold spinor atoms in optical lattices
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作者 CUI HaiTao YANG Gui TIAN JunLong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2128-2133,共6页
A scheme is proposed for detection of the topology in the one-dimensional Afeck-Kennedy-Lieb-Tasaki model,based on ultracold spinor atomic gas in an optical lattice.For this purpose,a global operation O(θ)is introduc... A scheme is proposed for detection of the topology in the one-dimensional Afeck-Kennedy-Lieb-Tasaki model,based on ultracold spinor atomic gas in an optical lattice.For this purpose,a global operation O(θ)is introduced with respect to the breaking of spinrotational symmetry.Consequently,the topology can be manifested unambiguously by identifying the special values ofθwhere the expectation value of the global operator with degenerate ground states is vanishing.Furthermore,experimentallyθcan be detected readily by the interference of ultracold atomic gases.This scheme can be implemented readily in experiment since it does not need the addressing of individual atoms or the probing of a boundary. 展开更多
关键词 global operator topology symmetry Afeck-Kennedy-Lieb-Tasaki model ultracold atoms
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Tests of gravitational symmetries with radio pulsars 被引量:2
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作者 LiJing Shao Norbert Wex 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第9期10-32,共23页
Symmetries play important roles in modern theories of physical laws. In this paper, we review several experimental tests of important symmetries associated with the gravitational interaction, including the universalit... Symmetries play important roles in modern theories of physical laws. In this paper, we review several experimental tests of important symmetries associated with the gravitational interaction, including the universality of free fall for self-gravitating bodies,time-shift symmetry in the gravitational constant, local position invariance and local Lorentz invariance of gravity, and spacetime translational symmetries. Recent experimental explorations for post-Newtonian gravity are discussed, of which, those from pulsar astronomy are highlighted. All of these tests, of very different aspects of gravity theories, at very different length scales, favor to very high precision the predictions of the strong equivalence principle(SEP) and, in particular, general relativity which embodies SEP completely. As the founding principles of gravity, these symmetries are motivated to be promoted to even stricter tests in future. 展开更多
关键词 GRAVITATION radio pulsars spacetime symmetry
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No Spin-Localization Phase Transition in the Spin-Boson Model without Local Field
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作者 刘涛 冯芒 +2 位作者 黎雷 杨万里 汪克林 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期637-641,共5页
We explore the spin-boson model in a special case, i.e., with zero local field. In contrast to previous studies, we find no possibility for quantum phase transition (QPT) happening between the localized and delocali... We explore the spin-boson model in a special case, i.e., with zero local field. In contrast to previous studies, we find no possibility for quantum phase transition (QPT) happening between the localized and delocalized phases, and the behavior of the model can be fully characterized by the even or odd parity as well as the parity breaking, instead of the QPT, owned by the ground state of the system. The parity breaking mentioned in our case is completely different from the spontaneously broken symmetry relevant to the conventionally defined QPT in previous studies. Our analytical treatment about the eigensolution of the ground state of the model presents for the first time a rigorous proof of no- degeneracy for the ground state of the model, which is independent of the bath type, the degrees of freedom of the bath and the calculation precision. We argue that the QPT mentioned previously appears due to incorrect employment of the ground state of the model and/or unreasonable treatment of the infrared divergence existing in the spectral functions for Ohmic and sub-Ohmic dissipations. 展开更多
关键词 spin-boson model localization phase transition parity breaking
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SU(2) symmetry in a Hubbard model with spin-orbit coupling
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作者 ZHANG XiZheng JIN Liang SONG Zhi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第11期2086-2091,共6页
We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction.It is shown that,in the absence of the on-site interaction,the system possesses the SU(2)symmetry arising from the ... We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction.It is shown that,in the absence of the on-site interaction,the system possesses the SU(2)symmetry arising from the time reversal symmetry.The influence of the on-site interaction on the symmetry depends on the topology of the networks:The SU(2)symmetry is shown to be the spin rotation symmetry of a simply-connected lattice even in the presence of the Hubbard interaction.On the contrary,the on-site interaction breaks the SU(2)symmetry of a multi-connected lattice.This fact indicates that a discrete spin-orbit coupled system has exclusive features from its counterpart in a continuous system.The obtained rigorous result is illustrated by a simple ring system. 展开更多
关键词 symmetry Hubbard orbit connected reversal rigorous contrary counterpart rotation tight
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