Regularisation of Lie algebroids and Applications

Álvaro del Pino; Aldo Witte

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arXiv · 2211.14891

Regularisation of Lie algebroids and Applications

Álvaro del Pino·Aldo Witte

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Abstract

We describe a procedure, called regularisation, that allows us to study geometric structures on Lie algebroids via foliated geometric structures on a manifold of higher dimension. This procedure applies to various classes of Lie algebroids; namely, those whose singularities are of b^k, complex-log, or elliptic type, possibly with self-crossings. One of our main applications is a proof of the Weinstein conjecture for overtwisted b^k-contact structures. This was proven by Miranda-Oms using a certain technical hypothesis. Our approach avoids this assumption by reducing the proof to the foliated setting. As a by-product, we also prove the Weinstein conjecture for other Lie algebroids. Along the way we also introduce tangent distributions, i.e. subbundles of Lie algebroids, as interesting objects of study and present a number of constructions for them.

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Álvaro del Pino, Aldo Witte. 2022-11-27. Regularisation of Lie algebroids and Applications. https://arxiv.org/abs/2211.14891

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