English

Natural transformations relating homotopy and singular homology functors

Algebraic Topology 2023-01-04 v1

Abstract

The category of topological spaces endowed with two marked points is equipped with two families Fn\mathbf F_n and Hn\mathbf H_n of functors to the category of abelian groups, indexed by a nonnegative integer nn: namely, the functor Fn\mathbf F_n takes the object (X,x,y)(X,x,y) to the quotient of Zπ1(X,x,y)\mathbb Z\pi_1(X,x,y) by an abelian subgroup associated with the n+1n+1-st power of the augmentation ideal of the group algebra Zπ1(X,x)\mathbb Z\pi_1(X,x), and the functor Hn\mathbf H_n takes the same object to the nn-th singular homology group of XnX^n relative to a subspace defined in terms of partial diagonals. We construct a family of natural transformations νn:FnHn\nu_n : \mathbf F_n\to \mathbf H_n. We identify the natural transformation obtained by restricting νn\nu_n to the subcategory of algebraic varieties with a natural equivalence due to Beilinson.

Keywords

Cite

@article{arxiv.2301.01157,
  title  = {Natural transformations relating homotopy and singular homology functors},
  author = {Benjamin Enriquez and Florence Lecomte},
  journal= {arXiv preprint arXiv:2301.01157},
  year   = {2023}
}

Comments

in French language