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A comment concerning cohomology and invariants of Lie algebras with respect to contractions and deformations

R. Campoamor-Stursberg
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Abstract

Contrary to the expected behavior, we show the existence of non-invertible deformations of Lie algebras which can generate invariants for the coadjoint representation, as well as delete cohomology with values in the trivial or adjoint module. A criterion to decide whether a given deformation is invertible or not is given in dependence of the Poincaré polynomial.

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R. Campoamor-Stursberg. 2006-08-17. A comment concerning cohomology and invariants of Lie algebras with respect to contractions and deformations. https://doi.org/10.1016/j.physleta.2006.10.050

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