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arXiv · 1508.01944

Functorial CW-approximation

Philip S. Hirschhorn
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Abstract

The usual construction of a CW-approximation is functorial up to homotopy, but it is not functorial. In this note, we construct a functorial CW-approximation. Our construction takes inclusions of subspaces into inclusions of subcomplexes, and commutes with intersections of subspaces of a fixed space.

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Philip S. Hirschhorn. 2015-08-08. Functorial CW-approximation. https://arxiv.org/abs/1508.01944

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