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A note on the geometry of linear Hamiltonian systems of signature 0 in R^4

James Montaldi
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Abstract

It is shown that a linear Hamiltonian system of signature zero in 4 dimensions is elliptic or hyperbolic according to the number of Lagrangian planes in the null-cone $H^{-1}(0)$, or equivalently the number of invariant Lagrangian planes. An extension to higher dimensions is described.

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James Montaldi. 2005-10-17. A note on the geometry of linear Hamiltonian systems of signature 0 in R^4. https://arxiv.org/abs/math/0510352

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