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Characterizing Complete Erdős Space

Published online by Cambridge University Press:  20 November 2018

Jan J. Dijkstra
Affiliation:
Faculteit der Exacte Wetenschappen/Afdeling Wiskunde, Vrije Universiteit, De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands, dijkstra@cs.vu.nlvanmill@cs.vu.nl
Jan van Mill
Affiliation:
Faculteit der Exacte Wetenschappen/Afdeling Wiskunde, Vrije Universiteit, De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands, dijkstra@cs.vu.nlvanmill@cs.vu.nl
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Abstract

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The space now known as complete Erdős space${{\mathfrak{E}}_{\text{c}}}$ was introduced by Paul Erdős in 1940 as the closed subspace of the Hilbert space ${{\ell }^{2}}$ consisting of all vectors such that every coordinate is in the convergent sequence $\left\{ 0 \right\}\cup \left\{ 1/n:n\in \mathbb{N}\ \right\}$. In a solution to a problem posed by Lex $G$. Oversteegen we present simple and useful topological characterizations of ${{\mathfrak{E}}_{\text{c}}}$. As an application we determine the class of factors of ${{\mathfrak{E}}_{\text{c}}}$. In another application we determine precisely which of the spaces that can be constructed in the Banach spaces ${{\ell }^{p}}$ according to the ‘Erdős method’ are homeomorphic to ${{\mathfrak{E}}_{\text{c}}}$. A novel application states that if $I$ is a Polishable ${{F}_{\sigma }}$-ideal on $\omega $, then $I$ with the Polish topology is homeomorphic to either $\mathbb{Z}$, the Cantor set ${{2}^{\omega }},\,\mathbb{Z}\,\times \,{{2}^{\omega }}$, or ${{\mathfrak{E}}_{\text{c}}}$. This last result answers a question that was asked by Stevo Todorčević.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2009

References

[1] Aarts, J. M. and Oversteegen, L. G., The geometry of Julia sets. Trans. Amer. Math. Soc. 338 (1993), no. 2, 897918.Google Scholar
[2] Abry, M. and Dijkstra, J. J., On topological Kadec norms. Math. Ann. 332 (2005), no. 4, 759765.Google Scholar
[3] Ancel, F. D., Dobrowolski, T., and Grabowski, J., Closed subgroups in Banach spaces. StudiaMath. 109 (1994), no. 3, 277290.Google Scholar
[4] Bessaga, C. and Pełczyński, A, Selected Topics in infinite-dimensional topology. Monografie Matematyczne 58, PWN–Polish Scientific Publishers, Warsaw, 1975.Google Scholar
[5] Bula, W. D. and Oversteegen, L. G., A characterization of smooth Cantor bouquets. Proc. Amer. Math. Soc. 108 (1990), no. 2, 529534.Google Scholar
[6] Charatonik, W. J., The Lelek fan is unique. Houston J. Math. 15 (1989), no. 1, 2734.Google Scholar
[7] Davis, W. J. andJohnson, W. B., A renorming of nonreflexive Banach spaces. Proc. Amer. Math. Soc. 37 (1973), 486488.Google Scholar
[8] Davis, W. J. and Lindenstrauss, J., On total nonnorming subspaces. Proc. Amer. Math. Soc. 31 (1972), 109111.Google Scholar
[9] Dijkstra, J. J., A criterion for Erdʺos spaces. Proc. Edinb. Math. Soc. (2) 48 (2005), no. 3, 595601.Google Scholar
[10] Dijkstra, J. J., A homogeneous space that is one-dimensional but not cohesive. Houston J. Math. 32 (2006), no. 4, 10931099.Google Scholar
[11] Dijkstra, J. J., Characterizing stable complete Erdʺos space. www.few.vu.nl/~dijkstra/research/papers/stable.pdfGoogle Scholar
[12] Dijkstra, J. J. and van Mill, J., Homeomorphism groups of manifolds and Erdʺos space. Electron. Res. Announc. Amer. Math. Soc. 10 (2004), 2938.Google Scholar
[13] Dijkstra, J. J. and van Mill, J., A counterexample concerning line-free groups and complete Erdʺos space. Proc. Amer. Math. Soc. 134 (2006), no. 8, 22812283.Google Scholar
[14] Dijkstra, J. J. and van Mill, J.. Erdʺos space and homeomorphism groups of manifolds. Mem. Amer. Math. Soc., to appear.Google Scholar
[15] Dijkstra, J. J., van Mill, J., and Steprans, J., Complete Erdős space is unstable, Math. Proc. Cambridge Philos. Soc. 137 (2004), 465473.Google Scholar
[16] Dijkstra, J. J., van Mill, J., and Valkenburg, K. I. S., On nonseparable Erdʺos spaces. J. Math. Soc. Japan 60 (2008), no. 3, 793818.Google Scholar
[17] Dobrowolski, T. and Grabowski, J., Subgroups of Hilbert spaces. Math. Z. 211 (1992), no. 4, 657669.Google Scholar
[18] Dobrowolski, T., Grabowski, J., and Kawamura, K., Topological type of weakly closed subgroups in Banach spaces. StudiaMath. 118 (1996), no. 1, 4962.Google Scholar
[19] van Engelen, A. J. M., Homogeneous zero-dimensional absolute Borel sets, CWI Tract, Vol. 27, Centre for Mathematics and Computer Science, Amsterdam, 1986.Google Scholar
[20] Erdʺos, P., The dimension of the rational points in Hilbert space. Ann. of Math. 41 (1940), 734736.Google Scholar
[21] Farah, I., Analytic quotients: theory of liftings for quotients over analytic ideals on the integers. Mem. Amer. Math. Soc. 148 (2000), no. 702.Google Scholar
[22] Kawamura, K., Oversteegen, L. G., and Tymchatyn, E. D., On homogeneous totally disconnected 1-dimensional spaces. Fund. Math. 150 (1996), no. 2, 97112.Google Scholar
[23] Kechris, A. S., Classical descriptive set theory. Graduate Texts in Mathematics 156, Springer-Verlag, New York, 1995.Google Scholar
[24] Kechris, A. S. and Louveau, A., The classification of hypersmooth Borel equivalence relations. J. Amer. Math. Soc. 10 (1997), no. 1, 215242.Google Scholar
[25] Lelek, A., On plane dendroids and their end points in the classical sense. Fund. Math. 49 (1960/1961), 301319.Google Scholar
[26] Mayer, J. C., An explosion point for the set of endpoints of the Julia set of ƛ exp(z). Ergodic Theory Dynam. Systems 10 (1990), no. 1, 177183.Google Scholar
[27] Mayer, J. C., Nikiel, J., and Oversteegen, L. G., Universal spaces for R-trees. Trans. Amer.Math. Soc. 334 (1992), no. 1, 411432.Google Scholar
[28] Mayer, J. C. and Oversteegen, L. G., A topological characterization of R-trees. Trans. Amer.Math. Soc. 320 (1990), no. 1, 395415.Google Scholar
[29] Mayer, J. C. and Oversteegen, L. G., Continuum theory. In: Recent Progress in General Topology, North-Holland, Amsterdam, 1992, pp. 453492.Google Scholar
[30] Oversteegen, L. G. and Tymchatyn, E. D., On the dimension of certain totally disconnected spaces. Proc. Amer. Math. Soc. 122 (1994), no. 3, 885891.Google Scholar
[31] Solecki, S., Analytic ideals. Bull. Symbolic Logic 2 (1996), no. 3, 339348.Google Scholar
[32] Solecki, S., Analytic ideals and their applications. Ann. Pure Appl. Logic 99 (1999), no. 1-3, 5172.Google Scholar
[33] Todorčević, S., Analytic gaps. Fund. Math. 150 (1996), no. 1, 5566.Google Scholar
[34] Trnková, V., Xm is homeomorphic to Xniffm n where is a congruence on natural numbers. Fund. Math. 80 (1973), no. 1, 5156.Google Scholar