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arXiv · 1506.08675

On the Relationship between Two Notions of Compatibility for Bi-Hamiltonian Systems

Manuele Santoprete
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Abstract

Bi-Hamiltonian structures are of great importance in the theory of integrable Hamiltonian systems. The notion of compatibility of symplectic structures is a key aspect of bi-Hamiltonian systems. Because of this, a few different notions of compatibility have been introduced. In this paper we show that, under some additional assumptions, compatibility in the sense of Magri implies a notion of compatibility due to Fass\`o and Ratiu, that we dub bi-affine compatibility. We present two proofs of this fact. The first one uses the uniqueness of the connection parallelizing all the Hamiltonian vector fields tangent to the leaves of a Lagrangian foliation. The second proof uses Darboux-Nijenhuis coordinates and symplectic connections.

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Manuele Santoprete. 2015-06-29. On the Relationship between Two Notions of Compatibility for Bi-Hamiltonian Systems. https://doi.org/10.3842/sigma.2015.089

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