Closed hypersurfaces of low entropy in $\mathbb{R}^4$ are isotopically trivial

Jacob Bernstein; Lu Wang

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arXiv · 2003.13858

Closed hypersurfaces of low entropy in $\mathbb{R}^4$ are isotopically trivial

Jacob Bernstein·Lu Wang

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Abstract

We show that any closed connected hypersurface in $\mathbb{R}^4$ with entropy less than or equal to that of the round cylinder is smoothly isotopic to the standard three-sphere.

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Jacob Bernstein, Lu Wang. 2020-03-30. Closed hypersurfaces of low entropy in $\mathbb{R}^4$ are isotopically trivial. https://arxiv.org/abs/2003.13858

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