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arXiv · 0906.2988

Non-Hamiltonian Actions and Lie-Algebra Cohomology of Vector Fields

Roberto Ferreiro Pérez·Jaime Muñoz Masqué
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Abstract

Two examples of $\mathrm{Diff}^+S^1$-invariant closed two-forms obtained from forms on jet bundles, which does not admit equivariant moment maps are presented. The corresponding cohomological obstruction is computed and shown to coincide with a nontrivial Lie algebra cohomology class on $H^2(\mathfrak{X}(S^1))$.

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Roberto Ferreiro Pérez, Jaime Muñoz Masqué. 2009-06-16. Non-Hamiltonian Actions and Lie-Algebra Cohomology of Vector Fields. https://doi.org/10.3842/sigma.2009.063

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