English

Functorial CW-approximation

Algebraic Topology 2015-08-11 v1

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.

Cite

@article{arxiv.1508.01944,
  title  = {Functorial CW-approximation},
  author = {Philip S. Hirschhorn},
  journal= {arXiv preprint arXiv:1508.01944},
  year   = {2015}
}

Comments

10 pages

R2 v1 2026-06-22T10:29:13.439Z