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arXiv · 1406.5595

Bihamiltonian cohomology of KdV brackets

Guido Carlet·Hessel Posthuma·Sergey Shadrin
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Abstract

Using spectral sequences techniques we compute the bihamiltonian cohomology groups of the pencil of Poisson brackets of dispersionless KdV hierarchy. In particular this proves a conjecture of Liu and Zhang about the vanishing of such cohomology groups.

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Guido Carlet, Hessel Posthuma, Sergey Shadrin. 2014-06-21. Bihamiltonian cohomology of KdV brackets. https://doi.org/10.1007/s00220-015-2540-4

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