共查询到20条相似文献,搜索用时 62 毫秒
1.
研究Birkhoff系统规范变换对其Noether对称性、Lie对称性和Mei对称性的影响.在一定条件下,Noether对称性和守恒量不改变.Lie对称性和Hojaman守恒量仍保持不变.Mei对称性和新型守恒量可能变化,得到了Mei对称性和新型守恒量保持不变的条件.举例说明结果的应用.
关键词:
Birkhoff系统
规范变换
对称性
守恒量 相似文献
2.
对完全各向同性Heisenberg铁磁链的LandauLifschitz方程的Hamilton理论建立中,Hamilton量的坐标积分和谱参数积分两种表示式不能协调地从单一守恒量导出的问题,利用规范变换完善地解决了.并可推广后处理非各向同性铁磁链的LandauLifschitz方程的Hamilton理论.
关键词:
规范变换
LandauLifschitz方程
守恒量
Hamilton理论 相似文献
3.
Conservation Quantities of the Explicit Symplectic Scheme for Time-evolution of Quantum System 总被引:2,自引:0,他引:2
Zhou Zhongyuan Ding Peizhu Institute of Atomic Molecular Physics Jilin University Changchun P R China Supported by National Natural Science Foundation of China State Commission of Science Technology Chinese Research Asso 《原子与分子物理学报》1997,(2)
ConservationQuantitiesoftheExplicitSymplecticSchemeforTime-evolutionofQuantumSystemZhouZhongyuanDingPeizhuInstituteofAtomican... 相似文献
4.
Amar Maheshwari 《Pramana》1986,27(3):383-391
The complete expression of the five-dimensional Einstein-Hilbert action as an expansion in fields in the Appelquist-Chodos
parametrization of the Kaluza-Klein metric has been given in this paper. It is explicitly shown that a unitary gauge can be
fixed in which in each of the charge sectors the vector and the scalar fields are absorbed as Goldstone modes leaving behind
the Pauli-Fierz Lagrangian for massive charged spin-2 field. 相似文献
5.
WU Lu-Sen XIAO Zhen-Jun 《理论物理通讯》2007,48(3):502-508
In this paper, we present the exact calculations for the vertex ^-sγb and ^sZb in the unitary gauge. We find that (a) the divergent- and μ-dependent terms are left in the effective vertex function Г^γμ(p, k) for b → sγ transition even after we sum up the contributions from four related Feynman diagrams; (b) for an on-shell photon, such terms do not contribute et al.; (c) for off-shell photon, these terms will be canceled when the contributions from both vertex ^sγb and ^sZb are taken into account simultaneously, and therefore the finite and gauge-independent function Zo(xt) = Co(xt) + Do(xt)/4, which governs the semi-leptonic decay b → sl^- l^+, is derived in the unitary gauge. 相似文献
6.
利用d’AlembertLagrange原理的Chaplygin形式在无限小变换下的变形形式得到Chaplygin系统的广义Noether等式和守恒量的形式.研究Chaplygin系统的形式不变性以及它与Noether对称性的关系.
关键词:
Chaplygin系统
Noether对称性
形式不变性
守恒量 相似文献
7.
Based on the strong magnetic anisotropy along the symmetry of the crystal, we construct a U(2) non-Abelian gauge potential for the molecular nanomagnet Mn12 by varying the external magnetic field adiabatically. Moreover, the non-Abelian geometric phase and the unitary matrix operation, which are the key steps to realize the universal holonomic quantum computing in the degenerate subspace, are also obtained by means of choosing an evolution path properly. 相似文献
8.
Thierry Lvy 《Journal of Geometry and Physics》2004,52(4):382-397
If G is any finite product of compact orthogonal, unitary and symplectic matrix groups, then Wilson loops generate a dense subalgebra of continuous observables on the configuration space of lattice gauge theory with structure group G. If G is orthogonal, unitary or symplectic, then Wilson loops associated to the natural representation of G are enough.
This extends a result of Sengupta [Proc. Am. Math. Soc. 1221 (3) (1994) 897] and earlier work by Durhuus [Lett. Math. Phys. 4 (6) (1980) 515]. In particular, our approach includes the cases of even orthogonal and symplectic groups. 相似文献
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A non-Noether conserved quantity, i.e., Hojman conserved quantity, constructed by using Mei symmetry for the nonholonomic controllable mechanical
system, is presented. Under general infinitesimal transformations, the
determining equations of the special Mei symmetry, the constrained restriction equations, the additional restriction equations, and the definitions of the weak Mei symmetry and the strong Mei symmetry of the nonholonomic controllable
mechanical system are given. The condition under which Mei symmetry is a Lie symmetry is obtained. The form of the Hojman conserved quantity of the
corresponding holonomic mechanical system, the weak Hojman conserved
quantity and the strong Hojman conserved quantity of the nonholonomic controllable mechanical system are obtained. An example is given to illustrate the application of the results. 相似文献
12.
Liao-fu Luo 《Frontiers of Physics in China》2009,4(2):241-251
The problem of the directionality of genome evolution is studied. Based on the analysis of C-value paradox and the evolution
of genome size, we propose that the function-coding information quantity of a genome always grows in the course of evolution
through sequence duplication, expansion of code, and gene transfer from outside. The function-coding information quantity
of a genome consists of two parts, p-coding information quantity that encodes functional protein and n-coding information
quantity that encodes other functional elements. The evidences on the law of the evolutionary directionality are indicated.
The needs of function are the motive force for the expansion of coding information quantity, and the information quantity
expansion is the way to make functional innovation and extension for a species. Therefore, the increase of coding information
quantity of a genome is a measure of the acquired new function, and it determines the directionality of genome evolution.
相似文献
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14.
研究非完整力学系统的Noether对称性导致的非Noether守恒量——Hojman守恒量. 在时间不变的特殊无限小变换下,给出系统的特殊Noether对称性与守恒量,并给出特殊Noether对称性导致特殊Lie对称性的条件. 由系统的特殊Noether对称性,得到相应完整系统的Hojman守恒量以及非完整系统的弱Hojman守恒量和强Hojman守恒量. 给出一个例子说明本结果的应用
关键词:
分析力学
非完整系统
Noether对称性
非Noether守恒量
Hojman守恒量 相似文献
15.
This paper studies a new conserved quantity which can be called
generalized Mei conserved quantity and directly deduced by Mei
symmetry of Birkhoff system. The conditions under which the Mei
symmetry can directly lead to generalized Mei conserved quantity and
the form of generalized Mei conserved quantity are given. An example
is given to illustrate the application of the results. 相似文献
16.
研究非完整力学系统的形式不变性导致的非Noether守恒量——Hojman守恒量. 在时间不变的特殊无限小变换下,给出非完整系统形式不变性的确定方程、约束限制方程和附加限制方程,提出并定义弱(强)形式不变性的概念. 研究特殊形式不变性导致特殊Lie对称性的条件,由系统的特殊形式不变性,得到相应完整系统的Hojman守恒量以及非完整系统的弱Hojman守恒量和强Hojman守恒量. 给出两个经典例子说明结果的应用.
关键词:
分析力学
非完整系统
形式不变性
非Noether守恒量
Hojman守恒量 相似文献
17.
研究Lagrange系统的Mei对称性直接导致的一种守恒量. 给出系统的Mei对称性的定义和判据方程, 得到系统Mei对称性直接导致的一种守恒量的条件和形式,并举例说明结果的应用.
关键词:
Lagrange系统
Mei对称性
守恒量 相似文献
18.
This paper studies a new type of conserved quantity which
is directly induced by Lie symmetry of the Lagrange system. Firstly, the
criterion of Lie symmetry for the Lagrange system is given. Secondly,
the conditions of existence of the new conserved quantity as well as
its forms are proposed. Lastly, an example is given to illustrate
the application of the result. 相似文献
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研究非保守Nielsen方程由形式不变性直接导致的非Noether守恒量.函数对时间的全导数采 用沿运动轨道曲线的方式,给出非保守Nielsen方程的非点的形式不变性的定义和判据,并 研究其Noether守恒量.得到形式不变性导致非Noether守恒量的条件以及守恒量的形式,并 给出三种特殊情形的推论.举例说明结果的应用.
关键词:
Nielsen方程
形式不变性
非Noether守恒量 相似文献