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arXiv · 1103.0434

Variational Lie derivative and cohomology classes

Marcella Palese·Ekkehart Winterroth
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Abstract

We relate cohomology defined by a system of local Lagrangian with the cohomology class of the system of local variational Lie derivative, which is in turn a local variational problem; we show that the latter cohomology class is zero, since the variational Lie derivative `trivializes' cohomology classes defined by variational forms. As a consequence, conservation laws associated with symmetries ensuring the vanishing of the second variational derivative of a local variational problem are globally defined.

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Marcella Palese, Ekkehart Winterroth. 2013-10-02. Variational Lie derivative and cohomology classes. https://doi.org/10.1063/1.3599134

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