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arXiv · 2407.13395

On Borsuk's non-retract theorem final version

Waldemar Sieg
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Abstract

The classical Borsuk's non-retract theorem asserts that a unit sphere in $\mathbb{R}^n$ is not a continuous retract of the unit closed ball. We will show that such a unit sphere is a piecewise continuous retract of the unit closed ball.

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Waldemar Sieg. 2024-07-18. On Borsuk's non-retract theorem final version. https://arxiv.org/abs/2407.13395

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