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arXiv · 0708.3157

The Maslov cocycle, smooth structures and real-analytic complete integrability

Leo T. Butler
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Abstract

This paper studies smooth obstructions to integrability and proves two main results. First, it is shown that if a smooth topological n-torus admits a real-analytically completely integrable convex hamiltonian on its cotangent bundle, then the torus is diffeomorphic to the standard n-torus. This is the first known result where the smooth structure of a manifold obstructs complete integrability. Second, it is proven that each one of the Witten-Kreck-Stolz 7-manifolds admit a real-analytically completely integrable geodesic flow on its cotangent bundle. This gives examples of topological manifolds all of whose smooth structures admit a real-analytically completely integrable convex hamiltonian on its cotangent bundle. Additional examples are provided by Eschenburgh and Aloff-Wallach spaces.

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Leo T. Butler. 2010-07-15. The Maslov cocycle, smooth structures and real-analytic complete integrability. https://doi.org/10.1353/ajm.0.0069

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