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1.
利用时间不变的无限小变换下的Lie对称性,研究广义经典力学中Raitzin正则方程的Hojman 守恒定理。建立广义Raitzin正则方程。给出无限小变换下Lie对称性的确定方程。建立系统的Hojman守恒定理,并举例说明结果的应用。  相似文献   

2.
广义经典力学系统的对称性与Mei守恒量   总被引:4,自引:0,他引:4       下载免费PDF全文
张毅 《物理学报》2005,54(7):2980-2984
研究广义经典力学系统的对称性和一类新型守恒量——Mei守恒量.在高维增广相空间中建立 了系统的运动微分方程;给出了系统的Mei对称性、Noether对称性和Lie对称性的判据;得 到了分别由三种对称性导致Mei守恒量的条件和Mei守恒量的形式.举例说明结果的应用. 关键词: 广义经典力学 Mei对称性 Noether对称性 Lie对称性 守恒量  相似文献   

3.
广义Hamilton系统的Lie对称性与守恒量   总被引:11,自引:3,他引:11       下载免费PDF全文
梅凤翔 《物理学报》2003,52(5):1048-1050
研究广义Hamilton系统Lie对称性导致的新型守恒量.首先,建立系统的微分方程.其次,研究一类特殊无限小变换下系统的Lie对称性.第三,将Hojman定理推广到广义Hamilton系统.最后,举例说明结果的应用. 关键词: 广义Hamilton系统 Lie对称性 守恒量  相似文献   

4.
非线性非完整系统Raitzin正则方程的Hojman守恒定理   总被引:1,自引:0,他引:1       下载免费PDF全文
利用时间不变的无限小变换下的Lie对称性,研究非线性非完整系统Raitzin正则方程的Hojman守恒定理.列出系统的运动微分方程.建立时间不变的无限小变换下的确定方程.给出系统的Hojman守恒定理,并举例说明结果的应用. 关键词: 非线性非完整系统 Raitzin正则方程 Lie对称性 确定方程 Hojman守恒 定理  相似文献   

5.
乔永芬  赵淑红  李仁杰 《物理学报》2006,55(11):5598-5605
提出广义Hamilton-Tabarrok-Leech正则方程的对称性理论.列写系统的运动方程.研究系统的Noether对称性、形式不变性和Lie对称性,并求出相应的守恒量.举例说明结果的应用. 关键词: 广义经典力学 H-T-L 正则方程 对称性 守恒量  相似文献   

6.
相空间中变质量力学系统的Hojman守恒量   总被引:1,自引:0,他引:1       下载免费PDF全文
方建会  张鹏玉 《物理学报》2004,53(12):4041-4044
研究一般的无限小变换下相空间中变质量力学系统Lie对称性的Hojman守恒量. 给出了相空 间中变质量力学系统Lie 对称性的确定方程和Hojman守恒量定理,并举例说明结果的应用. 关键词: 相空间 变质量系统 一般的无限小变换 Lie对称性 Hojman守恒量  相似文献   

7.
研究广义线性非完整力学系统的Lie对称性导致的Hojman守恒量,在时间不变的特殊Lie对称变换下,给出系统的Lie对称性确定方程、约束限制方程和附加限制方程,得到相应完整系统的Hojman守恒量以及广义线性非完整力学系统的弱Hojman守恒量和强Hojman守恒量,并举一算例说明结果的应用.  相似文献   

8.
乔永芬  赵淑红 《物理学报》2006,55(2):499-503
研究非保守系统广义Raitzin正则方程的形式不变性与非Noether守恒量.列出系统的Raitzin正则方程.提出在无限小变换下系统形式不变性的定义和判据.给出系统的形式不变性是Lie对称性的充要条件.建立Hojman守恒定理,并举例说明结果的应用. 关键词: 非保守系统 Raitzin正则方程 形式不变性 非Noether守恒量  相似文献   

9.
贾利群  孙现亭  张美玲  张耀宇  韩月林 《物理学报》2014,63(1):10201-010201
研究相对运动变质量完整系统Appell方程的广义Lie对称性及其直接导致的广义Hojman守恒量.在群的无限小变换下,给出相对运动变质量完整系统Appell方程广义Lie对称性的确定方程;得到相对运动变质量完整系统Appell方程广义Lie对称性直接导致的广义Hojman守恒量的表达式.最后,利用本文结果研究相对运动变质量完整约束的三自由度力学系统问题.  相似文献   

10.
准坐标下广义力学系统的Lie对称定理及其逆定理   总被引:62,自引:2,他引:60       下载免费PDF全文
研究准坐标下广义力学系统的Lie对称性与守恒量.首先,对准坐标下广义力学系统定义无限小生成元,并应用微分方程在无限小变换下不变性的Lie方法,建立系统的确定方程.其次,给出结构方程和守恒量的形式.最后,研究Lie对称性逆问题(由已知积分求Lie对称)并举例说明结果的应用. 关键词: 广义力学 准坐标 Lie对称 确定方程 结构方程 守恒量  相似文献   

11.
乔永芬  张耀良  韩广才 《中国物理》2002,11(10):988-992
In this paper,we present a general approach to the construction of conservation laws for generalized classical dynamical systems.Firstly,we give the definition of integrating factors and ,secondly,we study in detail the necessary conditions for the existence of conserved quantities.Then we establish the conservation theorem and its inverse for the hamilton‘s canonical equations of motion of holonomic nonconservative dynamical systems in generalized classical mechanics.Finally,we give an example to illustrate the application of the results.  相似文献   

12.
张毅  尚玫  梅凤翔 《中国物理》2000,9(6):401-407
In this paper, the symmetries and the conserved quantities for systems of generalized classical mechanics are studied. First, the generalized Noether's theorem and the generalized Noether's inverse theorem of the systems are given, which are based upon the invariant properties of the canonical action with respect to the action of the infinitesimal transformation of r-parameter finite group of transformation; second, the Lie symmetries and conserved quantities of the systems are studied in accordance with the Lie's theory of the invariance of differential equations under the transformation of infinitesimal groups; and finally, the inner connection between the two kinds of symmetries of systems is discussed.  相似文献   

13.
The object of this review is to discuss methods that enable one to trace the origin of symmetries and conservation laws in mechanics to geometrical symmetries of space-time. Starting with the basic Newtonian assumptions on absolute space and time classical mechanics is developed in configuration space and phase space independently together with the related structures such as force-less mechanics. Heuristic considerations on geometric symmetries in configuration space reveal their intimate relation to conservation laws. Using the methods of differential geometry this relationship is put on a formal footing and symmetry groups of all spherically symmetric single term potentials are classified. The method of infinitesimal canonical transformations is presented as an alternative method of deducing dynamical symmetries of an arbitrary system in phase space. These methods also apply to non-relativistic quantum theory. Possible extension to special and general relatively is also discussed.  相似文献   

14.
We study higher-order Lagrangian mechanics on thek-velocity manifold. The variational problem gives rise to new concepts, such as main invariants, Zermelo conditions, higher-order energies, and new conservation laws. A theorem of Noether type is proved for higher-order Lagrangians. The invariants to the infinitesimal symmetries are explicitly written. All this construction is a natural extension of classical Lagrangian mechanics.  相似文献   

15.
张丽香  刘汉泽  辛祥鹏 《物理学报》2017,66(8):80201-080201
运用李群分析,得到了广义(3+1)维Zakharov-Kuznetsov(ZK)方程的对称及约化方程,结合齐次平衡原理,试探函数法和指数函数法得到了该方程的群不变解和新精确解,包括冲击波解、孤立波解等.进一步给出了广义(3+1)维ZK方程的伴随方程和守恒律.  相似文献   

16.
A new conservation theorem derived directly from Mei symmetry of the generalized classical mechanical system is presented. First, the differential equations of motion of the system are established, and the definition and criterion of Mei symmetry for the system of generalized classical mechanics are given, which are based upon the invariance of dynamical functions under infinitesimal transformations. Second, the condition under which a Mei symmetry can lead to a new conservation law is obtained and the form of the conservation law is presented. And finally, an example is given to illustrate the application of the results.  相似文献   

17.
ZHANGYi 《理论物理通讯》2004,42(6):899-902
A new conservation theorem derived directly from Mei symmetry of the generalized classical mechanical system is presented. First, the differential equations of motion of the system are established, and the definition and criterion of Mei symmetry for the system of generalized classical mechanics are given, which are based upon the invariance of dynamical functions under irdinitesimal transformations. Second, the condition under which a Mei symmetry can lead to a new conservation law is obtained and the form of the conservation law is presented. And finadly, an example is given to illustrate the application of the results.  相似文献   

18.
We investigate Noether symmetries and conservation laws of the discrete nonconserved systems with nonregular lattices. The operators of discrete transformation and discrete differentiation to the right and left are introduced for the systems. Based on the invariance of discrete Hamilton action on nonregular lattices of the systems with the nonconserved forces under the infinitesimal transformations with respect to the time and generalized coordinates, we give the discrete analog of generalized variational f...  相似文献   

19.
We discuss nonlocal symmetries and nonlocal conservation laws that follow from the systematic potentialisation of evolution equations. Those are the Lie point symmetries of the auxiliary systems, also known as potential symmetries. We define higher-degree potential symmetries which then lead to nonlocal conservation laws and nonlocal transformations for the equations. We demonstrate our approach and derive second degree potential symmetries for the Burgers' hierarchy and the Calogero–Degasperis–Ibragimov–Shabat hierarchy.  相似文献   

20.
We investigate Noether symmetries and conservation laws of the discrete mechanico-electrical systems with nonregular lattices.The operators of discrete transformation and discrete differentiation to the right and left are introduced for the systems.Based on the invariance of discrete Hamilton action on nonregular lattices of the systems with the dissipation forces under the infinitesimal transformations with respect to the time,generalized coordinates and generalized charge quantities,we work out the discrete analog of the generalized variational formula.From this formula we derive the discrete analog of generalized Noether-type identity,and then we present the generalized quasi-extremal equations and properties of these equations for the systems.We also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the systems.Finally we use an example to illustrate these results.  相似文献   

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