English

n-Butterflies: Algebraically Modeling Morphisms between Homotopy n-Types

Algebraic Topology 2017-11-10 v3

Abstract

Crossed modules are known to be a model of pointed connected homotopy 2-types; formally, the homotopy category of crossed modules is equivalent to the category of pointed connected homotopy 2-types. In forming the homotopy category of crossed modules, one must resort to computing derived morphisms using non-constructive topological methods, but Behrang Noohi was able to find an algebraic model of these derived morphisms called butterflies. The result is a completely algebraic model of pointed connected homotopy 2-types. Reduced crossed complexes are a generalization of crossed modules and model a subclass of pointed connected homotopy types. We will present algebraic objects called n-butterflies which satisfy similar properties to butterflies and begin to generalize the theory of butterflies to model morphisms of pointed connected homotopy n-types.

Keywords

Cite

@article{arxiv.1711.01638,
  title  = {n-Butterflies: Algebraically Modeling Morphisms between Homotopy n-Types},
  author = {Ivan Dungan},
  journal= {arXiv preprint arXiv:1711.01638},
  year   = {2017}
}
R2 v1 2026-06-22T22:36:32.855Z