Using a new symmetry group theory, the transformation groups and symmetries of the general Broer-Kaup system are obtained. The results are much simpler than those obtained via the standard approaches.
In this paper, we introduce four models for the discrete horizontal symmetry in the gauge theory of electroweak interactions with left-right symmetry （i. e., the SU（2）L × SU（2）R × U（1） model） to obta...In this paper, we introduce four models for the discrete horizontal symmetry in the gauge theory of electroweak interactions with left-right symmetry （i. e., the SU（2）L × SU（2）R × U（1） model） to obtain four sets of the mixing angles among the different generations of leptons separately. In light of the corresponding mass relations obtained and the preliminary result for mv1 and mv2, we estimate the possible value of mv3 and discuss the various physical effects arising from the lepton mixing and non-vanishing mass of neutrinos in these four models, such as their influences on the determination of quark mixing angle and the representation of the μ-e universality, the neutrino oscillations and their applications in astrophysics and so on, with special emphasis on the life-time and various possible decay modes of v3 （its mass is about 2×102 Mev in Model B） so as to give a clue to experimental detection of v3.展开更多
Symmetry is conventionally described in a polarized manner that the system is either completely symmetric or completely asymmetric.Using group theoretical approach to overcome this dichotomous problem,we introduce the...Symmetry is conventionally described in a polarized manner that the system is either completely symmetric or completely asymmetric.Using group theoretical approach to overcome this dichotomous problem,we introduce the degree of symmetry(DoS) as a non-negative continuous number ranging from zero to unity.Do S is defined through an average of the fidelity deviations of Hamiltonian or quantum state over its transformation group G,and thus is computable by making use of the completeness relations of the irreducible representations of G.The monotonicity of Do S can effectively probe the extended group for accidental degeneracy while its multi-valued natures characterize some(spontaneous) symmetry breaking.展开更多
共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮...共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮(NTO)的热分解机理进行了系统研究和梳理,计算了共价键均裂的过渡态及能垒.结果表明,C—NO_(2)键均裂和随后的自由基复合是最优途径,能垒为216.9 k J·mol^(-1)(523 K).随后产生的NO自由基通过多次“复合-均裂”过程促进三唑中间体开环,分解为HNCO,N_(2)O和CO等小分子,它们相互反应又生成NO_(2),N_(2)和CO_(2).这些分解产物与诸多实验观测结果一致.展开更多
文摘Using a new symmetry group theory, the transformation groups and symmetries of the general Broer-Kaup system are obtained. The results are much simpler than those obtained via the standard approaches.
文摘In this paper, we introduce four models for the discrete horizontal symmetry in the gauge theory of electroweak interactions with left-right symmetry （i. e., the SU（2）L × SU（2）R × U（1） model） to obtain four sets of the mixing angles among the different generations of leptons separately. In light of the corresponding mass relations obtained and the preliminary result for mv1 and mv2, we estimate the possible value of mv3 and discuss the various physical effects arising from the lepton mixing and non-vanishing mass of neutrinos in these four models, such as their influences on the determination of quark mixing angle and the representation of the μ-e universality, the neutrino oscillations and their applications in astrophysics and so on, with special emphasis on the life-time and various possible decay modes of v3 （its mass is about 2×102 Mev in Model B） so as to give a clue to experimental detection of v3.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11421063,11534002,11475254the National 973Program under Grant Nos.2014CB921403,2012CB922104,and 2014CB921202
文摘Symmetry is conventionally described in a polarized manner that the system is either completely symmetric or completely asymmetric.Using group theoretical approach to overcome this dichotomous problem,we introduce the degree of symmetry(DoS) as a non-negative continuous number ranging from zero to unity.Do S is defined through an average of the fidelity deviations of Hamiltonian or quantum state over its transformation group G,and thus is computable by making use of the completeness relations of the irreducible representations of G.The monotonicity of Do S can effectively probe the extended group for accidental degeneracy while its multi-valued natures characterize some(spontaneous) symmetry breaking.
文摘共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮(NTO)的热分解机理进行了系统研究和梳理,计算了共价键均裂的过渡态及能垒.结果表明,C—NO_(2)键均裂和随后的自由基复合是最优途径,能垒为216.9 k J·mol^(-1)(523 K).随后产生的NO自由基通过多次“复合-均裂”过程促进三唑中间体开环,分解为HNCO,N_(2)O和CO等小分子,它们相互反应又生成NO_(2),N_(2)和CO_(2).这些分解产物与诸多实验观测结果一致.
