English

Cubical Approximation for Directed Topology II

Algebraic Topology 2026-02-02 v4 Category Theory

Abstract

The paper establishes an equivalence between directed homotopy categories of (diagrams of) cubical sets and (diagrams of) directed topological spaces. This equivalence both lifts and extends an equivalence between classical homotopy categories of cubical sets and topological spaces. Some simple applications include combinatorial descriptions and subsequent calculations of directed homotopy monoids and directed singular 1-cohomology monoids. Another application is a characterization of isomorphisms between small categories up to zig-zags of natural transformations as directed homotopy equivalences between directed classifying spaces. Cubical sets throughout the paper are taken to mean presheaves over the minimal symmetric monoidal variant of the cube category. Along the way, the paper characterizes morphisms in this variant as the interval-preserving lattice homomorphisms between finite Boolean lattices.

Keywords

Cite

@article{arxiv.2309.16619,
  title  = {Cubical Approximation for Directed Topology II},
  author = {Sanjeevi Krishnan},
  journal= {arXiv preprint arXiv:2309.16619},
  year   = {2026}
}

Comments

57 pages, 4 figures, corrected minor typos, statement, proof of Prop B.4 strengthened so that it implies Corollary 4.20, added one more acknowledgement

R2 v1 2026-06-28T12:35:11.585Z