Form invariance and new conserved quantity of generalised Birkhoffian system

A form invariance and a conserved quantity of the generalised Birkhoffian system are studied. First, a definition and a criterion of the form invariance are given. Secondly, through the form invariance, a new conserved quantity can be deduced. Finally, an example is given to illustrate the application of the result.

Three-order form invariance and conserved quantity

In this paper, the definition of three-order form invariance is given. Then the relation between the three-order form invariance and the three-order Lie symmetry is discussed and the sufficient and necessary condition of Lie symmetry, which comes from the three-order form invariance, is obtained. Finally a three-order Hojman conserved quantity is studied and an example is given to illustrate the application of the obtained results.

FORM INVARIANCE AND NOETHER SYMMETRICAL CONSERVED QUANTITY OF RELATIVISTIC BIRKHOFFIAN SYSTEMS

A form invariance of the relativistic Birkhoffian system is studied, and the conserved quantities of the system are obtained. Under the infinitesimal transformation of groups, the definition and criteria of the form invariance of the system were given. In view of the invariance of relativistic Pfaff_Birkhoff_ D'Alembert principle under the infinitesimal transformation of groups, the theory of Noether symmetries of the relativistic Birkhoffian system were constructed. The relation between the form invariance and the Noether symmetry is studied, and the results show that the form invariance can also lead to the Noether symmetrical conserved quantity of the relativistic Birkhoffian system under certain conditions.

Form invariance and conserved quantity for weakly nonholonomic system

The form invariance and the conserved quantity for a weakly nonholonomic system （WNS） are studied. The WNS is a nonholonomic system （NS） whose constraint equations contain a small parameter. The differential equations of motion of the system are established. The definition and the criterion of form invariance of the system are given. The conserved quantity deduced from the form invariance is obtained. Finally, an illustrative example is shown.

THE FORM INVARIANCES AND THE HOJMAN CONSERVED QUANTITIES FOR HAMILTON SYSTEMS

The form invariance and the Lie symmetry are defined for Hamilton systems.A relation between the form invariance and the Lie symmetry is derived.The Hojman conserved quantity is constructed by using the generators of Lie symmetry.An approach to find Hojman conserved quantities in terms of the form invariance is presented.An example is given to illustrate the application of the results.

On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived fromthem.Finally,an example is given to illustrate the application of the result.

Form Invariance and Noether Symmetries of Rotational Relativistic Birkhoff Systems

Under the infinitesimal transformations of groups, a form invariance of rotational relativistic Birkhoffsystems is studied and the definition and criteria are given. In view of the invariance of rotational relativistic PfaffBirkhoff D'Alcmbert principle under the infinitesimal transformations of groups, the theory of Noether symmetries ofrotational relativistic Birkhoff systems are constructed. The relation between the form invariance and the Noethersymmetries is studied, and the conserved quantities of rotational relativistic Birkhoff systems are obtained.

Lie-form invariance of nonholonomic mechanical systems

The Lie-form invariance of a nonholonomic mechanaical system is studied. The definition and criterion of the Lie-form invariance of the nonholonomic mechaaical system are given. The Hojman conserved quantity and a new type of conserved quantity are obtained from the Lie-form invariance. An example is givea to illustrate the application of the results.

Form Invariance and Noether Symmetries of Rotational Relativistic Birkhoff Systems

Under the infinitesimal transformations of groups, a form invariance of rotational relativistic Birkhoffsystems is studied and the definition and criteria are given. In view of the invariance of rotational relativistic PfaffBirkhoff D'Alcmbert principle under the infinitesimal transformations of groups, the theory of Noether symmetries ofrotational relativistic Birkhoff systems are constructed. The relation between the form invariance and the Noethersymmetries is studied, and the conserved quantities of rotational relativistic Birkhoff systems are obtained.

Noether-Form Invariance of Nonholonomic Controllable Mechanical Systems in Phase Space

In this paper,we study the Noether-form invariance of nonholonomic mechanical controllable systems inphase space.Equations of motion of the controllable mechanical systems in phase space are presented.The definitionand the criterion for this system are presented.A new conserved quantity and the Noether conserved quantity deducedfrom the Noether-form invariance are obtained.An example is given to illustrate the application of the results.

New non-Noether conserved quantities of mechanical system in phase space

This paper focuses on studying non-Noether conserved quantities of Lie symmetry and of form invariance for a mechanical system in phase space under the general infinitesimal transformation of groups. We obtain a new nonNoether conserved quantity of Lie symmetry of the system, and Hojman and Mei＇s results are of special cases of our con-clusion. We find a condition under which the form invariance of the system will lead to a Lie symmetry, and, further, obtain a new non-Noether conserved quantity of form invariance of the system. An example is given finally to illustrate these results.

完整力学系统的形式不变性与非Noether守恒量

研究完整力学系统的由形式不变性导致的非Noether守恒量.建立系统的运动方程和形式不变性的判据方程.给出形式不变性为Lie对称性的充分必要条件.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.举例说明结果的应用.

广义经典力学中完整系统Hamilton正则方程的形式不变性

研究广义力学中Hamilton正则方程的形式不变性.给出正则方程形式不变性的定义和判据.建立形式不变性与系统守恒量之间的关系,并举例说明结果的应用.

有多余坐标的完整系统形式不变性导致的新守恒量

研究有多余坐标的完整力学系统由形式不变性直接导出的新型守恒量。用有多余坐标的双面理想完整约束力学系统的运动微分方程和约束方程在无限小变换下的形式不变性,给出系统形式不变性的定义和判据。得到形式不变性导致守恒量的条件以及守恒量的形式,并给出三种特殊情形下的推论。举例说明结果的应用。

事件空间中完整系统运动方程的形式不变性

研究事件空间中完整力学系统在群的无限小变换下的形式不变性.给出形式不变性的定义和判据,研究形式不变性导致守恒量的条件以及守恒量的形式.举例说明结果的应用.

相对论Birkhoff系统的形式不变性与Noether守恒量

研究相对论Birkhoff系统的形式不变性,寻求系统的守恒量。在群的无限小变换下,给出相对论Birkhoff系统的形式不变性的定义和判剧。基于相对论Pfaff-Birkhoff-D’Alembert原理在群的无限小变换下的变形形式,建立相对论Birkhoff系统的Noether对称性理论。通过研究形式不变性与Noether对称性之间的关系,得到相对论Birkhoff系统的守恒量。研究结果表明:在一定的条件下,相对论Birkhoff系统的形式不变性导致Noether对称性的守恒量。

变质量完整力学系统的形式不变性与非Noether守恒量

利用时间不变的特殊无限小变换下的形式不变性 ,研究变质量完整力学系统的非 Noether守恒量 .建立系统的运动微分方程 ,研究特殊无限小变换下系统形式不变性的定义和判据 ,给出形式不变性为 L ie对称性的充要条件 ,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 ,举例说明结果的应用 .

完整力学系统准坐标下运动方程的形式不变性

对称性方法是寻求守恒量的近代方法 .形式不变性是一种新的对称性 .研究完整力学系统准坐标表示的运动微分方程在群的无限小变换下的形式不变性 .给出形式不变性的定义和判据 .研究形式不变性导致守恒量的条件 。

广义Chaplygin系统的形式不变性与Noether对称性

研究广义Chaplygin系统的形式不变性,利用广义Chaplygin方程在无限小变换下的变形形式,给出广义Chaplygin系统的形式不变性的定义和判据.给出了广义Chaplygin系统的Noether对称性判据,并研究形式不变性和Noether对称性的关系.结果表明形式不变性与Noether对称性是两种不同的对称性,广义Chaplygin方程的形式不变性有可能是Noether对称性,也可能不是Noether对称性.最后举例说明结果的应用.