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arXiv · 1705.08446

Symmetries of the equations of motion that are not shared by the Lagrangian

G. F. Torres del Castillo·A. Moreno-Ruiz
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Abstract

We show that if a Lagrangian is invariant under a transformation (with the invariance defined in the standard manner), then the equations of motion obtained from it maintain their form under the transformation. We also show that the converse is not true, giving examples of equations of motion that are form-invariant under a transformation, but these equations can be derived from a Lagrangian that is not invariant under such transformation. The conclusions are valid for discrete or continuous systems.

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G. F. Torres del Castillo, A. Moreno-Ruiz. 2017-05-23. Symmetries of the equations of motion that are not shared by the Lagrangian. https://arxiv.org/abs/1705.08446

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