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Inverse systems with simplicial bonding maps and cell structures. (English) Zbl 1483.54006

The main result of the paper is: given a topologically complete space \(X\) and a “defining family of closed covers” \(\mathcal{A}\) of \(X\) (i.e., it satisfies some local refinement condition and completeness condition), to construct an inverse system \({\mathbf F}_{\mathcal A} = (F_{\lambda}, \pi_{\lambda}^{\mu}, \Lambda)\) of simplicial complexes and simplicial bonding maps, and an inverse system \({\mathbf N}_{\mathcal A} = (N_{\lambda}, \pi_{\lambda}^{\mu}, \Lambda)\) such that the limit spaces \(F_{\infty} = N_{\infty}\), where \(N_{\lambda}\) is a subcomplex of \(F_{\lambda}\) which is almost the same as a cover, and to obtain a proper map \(\pi: N_{\infty} \to X\), and a continuous map \(p: X\to N_{\infty}\) so that \(\pi\circ p = {\mathrm {id}}_X\) and the two maps \(p\circ \pi\) and \({\mathrm {id}}_{N_{\infty}}\) are homotopic (so \(N_{\infty}\) is homotopy equivalent to \(X\)). The construction of the inverse system is based on a modification of the theorem by S. Mardešić [Fundam. Math. 114, 53–78 (1981; Zbl 0411.54019)] that every topological space \(X\) admits a polyhedral resolution.
The authors then show that if \(X\) is a compact Hausdorff space and \(\mathcal{A}\) is a family of locally finite, normal, closed covers of \(X\) satisfying the local refinement condition, then the inverse systems \({\mathbf F}_{\mathcal A}\) and \({\mathbf N}_{\mathcal A}\) are HPol-expansions of \(N_{\infty}\) and hence of \(X\), where an expansion is in the shape theoretical sense.
They also show that the restricted inverse system \({\mathbf F}^{(0)} = (F_{\lambda}^{(0)}, \pi_{\lambda}^{\mu}, \Lambda)\) is a cell structure in the sense of [W. Dębski and E. D. Tymchatyn, Topology Appl. 239, 293–307 (2018; Zbl 1390.54014)] representing a space canonically homeomorphic to \(X\).

MSC:

54C05 Continuous maps
54B35 Spectra in general topology
54D30 Compactness
54E15 Uniform structures and generalizations
78A70 Biological applications of optics and electromagnetic theory

References:

[1] Davis, Michael W.; Moussong, Gábor, Notes on nonpositively curved polyhedra (2004), lecture note · Zbl 0961.53022
[2] Dębski, Wojciech; Tymchatyn, E. D., Cell structures and completely metrizable spaces and their mappings, Colloq. Math., 147, 181-194 (2017) · Zbl 1382.54018
[3] Dębski, Wojciech; Tymchatyn, E. D., Cell structures and topologically complete spaces, Topol. Appl., 239, 293-307 (2018) · Zbl 1390.54014
[4] Dydak, Jerzy, Cohomological dimension theory, (Daverman, R. J.; Sher, R. B., Handbook of Geometric Topology (2002), North-Holland: North-Holland Amsterdam), 423-470 · Zbl 0992.55001
[5] Engelking, Ryszard, General Topology, Sigma Series in Pure Mathematics, vol. 6 (1989), Heldermann Verlag: Heldermann Verlag Berlin · Zbl 0684.54001
[6] Freudenthal, Hans, Entwicklungen von Räumen und ihren Gruppen, Compos. Math., 4, 145-234 (1937) · Zbl 0016.28001
[7] Mardešić, Sibe, Approximate polyhedra, resolutions of maps and shape fibrations, Fundam. Math., 114, 53-78 (1981) · Zbl 0411.54019
[8] Mardešić, Sibe, Absolute neighborhood retracts and shape theory, (James, I. M., History of Topology (1999), Elsevier Science B.V.), Chapter 9 · Zbl 0973.54002
[9] Mardešić, Sibe, Not every metrizable compactum is the limit of an inverse sequence with simplicial bonding maps, Topol. Appl., 239, 120-122 (2018) · Zbl 1388.54011
[10] Mardešić, Sibe; Segal, Jack, Shape Theory, the Inverse System Approach, North-Holland Mathematical Library, vol. 25 (1982), North-Holland · Zbl 0996.54002
[11] Milnor, John, On spaces having the homotopy type of a CW-complex, Trans. Am. Math. Soc., 90, 272-280 (1959) · Zbl 0084.39002
[12] Morita, Kiiti, Čech cohomology and covering dimension for topological spaces, Fundam. Math., 87, 31-52 (1975) · Zbl 0336.55003
[13] Morita, Kiiti, On shapes of topological spaces, Fundam. Math., 86, 251-259 (1975) · Zbl 0296.54034
[14] Rubin, Leonard R.; Tonić, Vera, Simplicial inverse sequences in extension theory, preprint available at · Zbl 1305.55002
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