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Diffeomorphisms and almost complex structures on tori

Boguslaw Hajduk·Aleksy Tralle
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Abstract

We prove that there exist diffeomorphisms of tori, supported in a disc, which are not isotopic to symplectomorphisms with respect to any symplectic structure. This yields a partial negative answer to a question of Benson and Gordon about the existence of symplectic structures on tori with exotic differential structure.

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Boguslaw Hajduk, Aleksy Tralle. 2007-06-22. Diffeomorphisms and almost complex structures on tori. https://arxiv.org/abs/math/0311412

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