【摘 要】
：
研究了广义Birkhoff系统的3种对称性及其相应的守恒量.首先,基于Pfaffian作用量在无限小变换下的不变性,建立了广义Birkhoff系统的Noether理论;其次,基于微分方程在无限小变
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研究了广义Birkhoff系统的3种对称性及其相应的守恒量.首先,基于Pfaffian作用量在无限小变换下的不变性,建立了广义Birkhoff系统的Noether理论;其次,基于微分方程在无限小变换下的不变性,建立了广义Birkhoff系统的Lie对称性的定义和判据,给出了由系统的Lie对称性直接导致的Hojman守恒量;最后,基于力学系统运动微分方程中出现的动力学函数在经历无限小变换后仍然满足原来方程的一种不变性,建立了广义Birkhoff系统的Mei对称性的定义和判据,给出了由系统的Mei对称性直接导致的Mei守恒量.举例说明了结果的应用.
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