×

On the homotopy types of 2-connected and 6-dimensional CW-complexes. (English) Zbl 1540.55012

This paper is concerned with the classification of \(2\)-connected \(6\)-dimensional CW-complexes. Under the assumption that \(H_3(X)\) is uniquely \(2\)-divisible (i.e., \(H_3(X)\otimes\mathbb{Z}_2=0\) and \(\mathrm{Tor}(H_3(X),\mathbb{Z}_2)\)=0), the author shows that the Whitehead exact sequence \[ H_6(X)\to \Gamma_5(X) \to \pi_5(X)\twoheadrightarrow H_5(X) \] provides a complete invariant for the homotopy classification of such complexes.
As an application, the author shows that there exist exactly three homotopy types among \(2\)-connected \(6\)-dimensional CW-complexes with \[ H_3(X)\cong \mathbb{Z}_n, H_4(X)\cong\mathbb{Z}_m, H_5(X)\cong\mathbb{Z}_p, H_6(X)\cong\mathbb{Z}, \] where \(n\) is odd and \(m,p\) are even.

MSC:

55P15 Classification of homotopy type
55U99 Applied homological algebra and category theory in algebraic topology
55Qxx Homotopy groups
Full Text: DOI

References:

[1] Baues, H. J., Homotopy Type and Homology, 1996, Oxford: Clarendon Press, Oxford · Zbl 0857.55001 · doi:10.1093/oso/9780198514824.001.0001
[2] Félix, Y.; Halperin, S.; Thomas, J.-C., Rational Homotopy Theory, 2001, New York: Springer, New York · Zbl 0961.55002
[3] Whitehead, J. H. C., A certain exact sequence, Ann. Math., 52, 51-110, 1950 · Zbl 0037.26101 · doi:10.2307/1969511
[4] Benkhalifa, M., The effect of cell-attachment on the group of self-equivalences of an elliptic space, Mich. Math. J., 71, 3, 611-617, 2022 · Zbl 1497.55015
[5] Benkhalifa, M., On the group of self-homotopy equivalences of an elliptic space, Proc. Am. Math. Soc., 148, 6, 2695-2706, 2020 · Zbl 1437.55012 · doi:10.1090/proc/14900
[6] Benkhalifa, M., On the group of self-homotopy equivalences of \((n+1)\)-connected and \((3n+2)\)-dimensional CW-complex, Topology Appl., 233, 1-15, 2018 · Zbl 1378.55004 · doi:10.1016/j.topol.2017.10.018
[7] Benkhalifa, M., Postnikov decomposition and the group of self-equivalences of a rationalized space, Homology Homotopy Appl., 19, 1, 209-224, 2017 · Zbl 1380.55005 · doi:10.4310/HHA.2017.v19.n1.a11
[8] Benkhalifa, M., On the classification problem of the quasi-isomorphism classes of free chain algebras, J. Pure Appl. Algebra, 210, 2, 343-362, 2007 · Zbl 1122.55007 · doi:10.1016/j.jpaa.2006.09.012
[9] Benkhalifa, M., On the homotopy type of a chain algebra, Homology Homotopy Appl., 6, 109-135, 2004 · Zbl 1070.55010 · doi:10.4310/HHA.2004.v6.n1.a8
[10] Benkhalifa, M., Sur le type d’homotopy d’un CW-complexe, Homology Homotopy Appl., 5, 1, 101-120, 2003 · Zbl 1041.55004 · doi:10.4310/HHA.2003.v5.n1.a6
[11] MacLane, S., Homology, 1963, Berlin-Göttingen-Heidelberg: Springer, Berlin-Göttingen-Heidelberg · Zbl 0133.26502 · doi:10.1007/978-3-642-62029-4
[12] Baues, H. J.; Goerss, P., A homotopy operation spectral sequence for the computation of homotopy groups, Topology, 39, 1, 161-192, 2000 · Zbl 0958.55013 · doi:10.1016/S0040-9383(98)00065-2
[13] Miller, C., The second homology group of group; relations among commutators, Proc. Am. Math. Soc., 3, 588-595, 1952 · Zbl 0047.25703 · doi:10.1090/S0002-9939-1952-0049191-5
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.