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arXiv · 1307.1983

On the connections between symmetries and conservation rules of dynamical systems

Giampaolo Cicogna
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Abstract

The strict connection between Lie point-symmetries of a dynamical system and its constants of motion is discussed and emphasized, through old and new results. It is shown in particular how the knowledge of a symmetry of a dynamical system can allow to obtain conserved quantities which are invariant under the symmetry. In the case of Hamiltonian dynamical systems it is shown that, if the system admits a symmetry of "weaker" type (specifically, a λ or a Λ-symmetry), then the generating function of the symmetry is not a conserved quantity, but the deviation from the exact conservation is "controlled" in a well defined way. Several examples illustrate the various aspects.

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Giampaolo Cicogna. 2013-07-08. On the connections between symmetries and conservation rules of dynamical systems. https://doi.org/10.1002/mma.2584

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