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arXiv · 2101.03534

Symplectic excision

Yael Karshon·Xiudi Tang
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Abstract

We use time-independent incomplete Hamiltonian flows to excise interesting closed subsets of positive codimension from symplectic manifolds. Examples of such subsets include what we call a "Cantor brush", a "box with a tail", and -- more generally -- epigraphs of lower semicontinuous functions. This answers a question of Alan Weinstein about excision of a ray, and it generalizes a result of Bernd Stratmann about excision of the product of a ray with a manifold.

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BibTeXRIS

Yael Karshon, Xiudi Tang. 2021-01-10. Symplectic excision. https://doi.org/10.2140/gt.2026.30.2217

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