On the homotopy theory of stratified spaces

Abstract

Let $P$ be a poset. We define a new homotopy theory of suitably nice $P$-stratified topological spaces with equivalences on strata and links inverted. We show that the exit-path construction of MacPherson, Treumann, and Lurie defines an equivalence from our homotopy theory of $P$-stratified topological spaces to the $\infty$-category of $\infty$-categories with a conservative functor to $P$. This proves a stratified form of Grothendieck's homotopy hypothesis, verifying a conjecture of Ayala-Francis-Rozenblyum. Our homotopy theory of stratified spaces has the added benefit of capturing all examples of geometric interest: conically stratified spaces fit into our theory, and the Ayala-Francis-Tanaka-Rozenblyum homotopy theory of conically smooth stratified spaces embeds into ours.

v6: 33 pages. Many parts have been rewritten in response to referee comments. The appendix has been removed and replaced by citations to Douteau's work. Final version to appear in Annales scientifiques de l'École normale supérieure