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arXiv · 1201.3728

The Conley-Zehnder index for a path of symplectic matrices

Jean Gutt
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Abstract

We give here a self contained and elementary introduction to the Conley-Zehnder index for a path of symplectic matrices. We start from the definition of the index as the degree of a map into the circle for a path starting at the identity and ending at a matrix for which 1 is not an eigenvalue. We prove some properties which characterize this index using normal forms for symplectic matrices obtained from geometrical considerations. We explore the relations to Robbin-Salamon index for paths of Lagrangians. We give an axiomatic characterization of the generalization of the Conley-Zehnder index for any continuous path of symplectic matrices defined by Robbin and Salamon.

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Jean Gutt. 2012-02-12. The Conley-Zehnder index for a path of symplectic matrices. https://arxiv.org/abs/1201.3728

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