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371.
In this paper the Lie-form invariance of the non-holonomic systems with
unilateral constraints is studied. The definition and the criterion of the
Lie-form invariance of the system are given. The generalized Hojman
conserved quantity and a new type of conserved quantity deduced from the
Lie-form invariance are obtained. Finally, an example is presented to
illustrate the application of the results. 相似文献
372.
In this paper, a new kind of symmetry and its conserved quantities of a mechanical
system in phase space are studied. The definition of this new symmetry, i.e. a
Noether--Lie symmetry, is presented, and the criterion of this symmetry is also
given. The Noether conserved quantity and the generalized Hojman conserved quantity
of the Noether--Lie symmetry of the system are obtained. The Noether--Lie symmetry
contains the Noether symmetry and the Lie symmetry, and has more generalized
significance. 相似文献
373.
Unified Symmetry of Hamilton Systems 总被引:1,自引:0,他引:1
XU Xue-Jun QIN Mao-Chang MEI Feng-Xiang 《理论物理通讯》2005,44(5):769-772
The definition and the criterion of a unified symmetry for a Hamilton system are presented. The sufficient condition under which the Noether symmetry is a unified symmetry for the system is given. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity deduced from the unified symmetry, is obtained. An example is finally given to illustrate the application of the results. 相似文献
374.
Conformal invariance and a new type of conserved quantities of mechanical systems with variable mass in phase space are studied. Firstly, the definition and determining equation of conformal invariance are presented. The relationship between the conformal invariance and the Lie symmetry is given, and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry under the infinitesimal transformations is provided.Secondly, a new type of conserved quantities of the conformal invariance are obtained by using the Lie symmetry of the system. Lastly, an example is given to illustrate the application of the results. 相似文献
375.
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
376.
Conformal invariance and conserved quantities of dynamical system of relative motion 总被引:1,自引:0,他引:1
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This paper discusses in detail the conformal invariance by
infinitesimal transformations of a dynamical system of relative
motion. The necessary and sufficient conditions of conformal
invariance and Lie symmetry are given simultaneously by the action
of infinitesimal transformations. Then it obtains the conserved
quantities of conformal invariance by the infinitesimal
transformations. Finally an example is given to illustrate the
application of the results. 相似文献
377.
XU Xue-Jun QIN Mao-Chang MEI Feng-Xiang 《理论物理通讯》2005,44(11)
The definition and the criterion of a unified symmetry for a Hamilton system are presented. The sufficient condition under which the Noether symmetry is a unified symmetry for the system is given. A new conserved quantity,as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, is obtained. An example is finally given to illustrate the application of the results. 相似文献
378.
For the holonomic nonconservative
system, by using the Noether symmetry, a non-Noether conserved quantity is
obtained directly under general infinitesimal transformations of groups in which time is variable. At first, the Noether symmetry, Lie symmetry, and
Noether conserved quantity are given. Secondly, the condition under which
the Noether symmetry is a Lie symmetry under general infinitesimal
transformations is obtained. Finally, a set of non-Noether conserved
quantities of the system are given by the Noether symmetry, and an example is
given to illustrate the application of the results. 相似文献
379.
研究相对论性变质量系统的守恒律.给出相对论性变质量系统的d’Alembert-Lagrange原理,利用其在无限小变换下的不变性条件,得到相对论性变质量系统的守恒律存在的条件和形式,并举例说明结果的应用
关键词:
相对论
分析力学
变质量
守恒律 相似文献
380.
Michael G. Mürmann 《Journal of statistical physics》2001,105(3-4):483-510
We study the hydrodynamic limit of a deterministic one-dimensional particle system with nearest neighbour interaction and an additional regularizing force. Under its evolution mass and momentum are conserved. In the limit with Euler scaling their macroscopic distributions are shown to be governed by the compressible Navier–Stokes equations with a density dependent viscosity. 相似文献