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arXiv · 0807.1294

Central extensions of cotangent universal hierarchy: (2+1)-dimensional bi-Hamiltonian systems

Artur Sergyeyev·Blazej M. Szablikowski
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Abstract

We introduce the cotangent universal hierarchy that extends the so-called universal hierarchy (as for the latter, see e.g. arXiv:nlin/0202008, arXiv:nlin/0312043 and arXiv:nlin/0310036). Then we construct a (2+1)-dimensional double central extension of the cotangent universal hierarchy and show that this extension is bi-Hamiltonian. This yields, as a byproduct, the central extension of the original universal hierarchy.

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Artur Sergyeyev, Blazej M. Szablikowski. 2008-09-23. Central extensions of cotangent universal hierarchy: (2+1)-dimensional bi-Hamiltonian systems. https://doi.org/10.1016/j.physleta.2008.10.020

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