Eilenberg-MacLane spaces in A-homotopy theory
Abstract
In this paper we study a discrete homotopy theory for undirected graphs. More precisely, we consider A-homotopy groups, first defined in the work of Barcelo, Kramer, Laubenbacher and Weaver. For every degree n and every group G (Abelian if n≥ 2), we construct a graph whose n-th A-homotopy group is isomorphic to G and whose other A-homotopy groups all vanish. Using these, we show that for every infinite sequence of groups G1,G2,…, with Gi Abelian for i≥ 2, there is a graph X such that the i-th A-homotopy group of X is isomorphic to Gi for all i. Along the way, we identify relative A-homotopy groups with relative classical homotopy groups, and prove a discrete version of the Blakers-Massey theorem. We then construct partial Postnikov systems and (full) Whitehead towers.
Related
- A complete classification of the rational realization of gap-two products of Eilenberg--MacLane spaces as classifying spaces
- On The Rational Realization of Even-dimensional Spheres and Products of Eilenberg--MacLane Spaces as Classifying Spaces
- Compact quotients of homogeneous spaces and homotopy theory of sphere bundles
- Complex Projective Spaces in Rational SO(2)-Equivariant Stable Homotopy Theory
- Motivic Eilenberg--Mac Lane spaces at the characteristic
BibTeX
@misc{wille2026eilenbergmaclane,
title = {{Eilenberg-MacLane spaces in A-homotopy theory}},
author = {Georg Wille},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.03497},
eprint = {2610.03497},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.03497},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Eilenberg-MacLane spaces in A-homotopy theory
AU - Georg Wille
PY - 2026
DA - 2026/10/02
PB - arXiv
DO - 10.48550/arxiv.2610.03497
UR - https://arxiv.org/abs/2610.03497
AB - In this paper we study a discrete homotopy theory for undirected graphs. More precisely, we consider A-homotopy groups, first defined in the work of Barcelo, Kramer, Laubenbacher and Weaver. For every degree n and every group G (Abelian if n≥ 2), we construct a graph whose n-th A-homotopy group is isomorphic to G and whose other A-homotopy groups all vanish. Using these, we show that for every infinite sequence of groups G_1,G_2,…, with G_i Abelian for i≥ 2, there is a graph X such that the i-th A-homotopy group of X is isomorphic to G_i for all i. Along the way, we identify relative A-homotopy groups with relative classical homotopy groups, and prove a discrete version of the Blakers-Massey theorem. We then construct partial Postnikov systems and (full) Whitehead towers.
ER -