Journals / Hacettepe Journal of Mathematics and Statistics / 2019 / Volume: 48 Issue: 6

On selective sequential separability of function spaces with the compact-open topology

Alexander V. Osipov(Ural State University of Economics)0000-0002-6460-1943
Pages
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Publication Date
2019-12-08
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⚡ TL;DR(Too Long; Didn't Read)

In this paper, we give a characterization for $C_k(X)$ to satisfy $S_{fin}(\mathcal{S},\mathcal{S})$.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:For a Tychonoff space $X$, we denote by $C_k(X)$ the space of all real-valued continuous functions on $X$ with the compact-open topology.
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Key Findings & Data:A subset $A\subset X$ is said to be sequentially dense in $X$ if every point of $X$ is the limit of a convergent sequence in $A$.
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Conclusion & Impact:In this paper, we give a characterization for $C_k(X)$ to satisfy $S_{fin}(\mathcal{S},\mathcal{S})$.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:compact-open topology · function space · selectively sequentially separable

Abstract

For a Tychonoff space $X$, we denote by $C_k(X)$ the space of all real-valued continuous functions on $X$ with the compact-open topology. A subset $A\subset X$ is said to be sequentially dense in $X$ if every point of $X$ is the limit of a convergent sequence in $A$. A space $C_k(X)$ is selectively sequentially separable (in Scheepers' terminology: $C_k(X)$ satisfies $S_{fin}(\mathcal{S},\mathcal{S})$) if whenever $(S_n : n\in \mathbb{N})$ is a sequence of sequentially dense subsets of $C_k(X)$, one can pick finite $F_n\subset S_n$ ($n\in \mathbb{N}$) such that $\bigcup \{F_n: n\in \mathbb{N}\}$ is sequentially dense in $C_k(X)$. In this paper, we give a characterization for $C_k(X)$ to satisfy $S_{fin}(\mathcal{S},\mathcal{S})$.

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Cite This Article

Osipov, A. V. (2019). On selective sequential separability of function spaces with the compact-open topology. Hacettepe Journal of Mathematics and Statistics, Volume: 48 Issue: 6. https://doi.org/10.15672/HJMS.2018.635

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References (27)

  1. A.V. Arhangel’skii, The frequency spectrum of a topological space and the classification of spaces, Soviet Math. Dokl. 13, 1186–1189, 1972.
  2. A. Bella, M. Bonanzinga, and M. Matveev, Variations of selective separability, Topol. App. 156, 1241–1252, 2009.
  3. A. Bella, M. Bonanzinga, and M. Matveev, Sequential+separable vs sequentially separable and another variation on selective separability, Cent. Eur. J. Math. 11 (3), 530–538, 2013.
  4. A. Bella and C. Costantini, Sequential Separability vs Selective Sequential Separability, Filomat 29 (1), 121–124, 2015.
  5. A. Caserta, G. Di Maio, Lj.D.R. Kočinac, and E. Meccariello, Applications of k-covers II, Topol. App. 153, 3277–3293, 2006.
  6. P. Gartside, J.T.H. Lo, and A. Marsh, Sequential density, Topol. App. 130, 75–86, 2003.
  7. G. Gruenhage and M. Sakai, Selective separability and its variations, Topol. App. 158 (12), 1352–1359, 2011.
  8. Lj.D.R. Kočinac, Closure properties of function spaces, App. Gen. Top. 4 (2), 255– 261, 2003.
  9. Lj.D.R. Kočinac, $\gamma$-sets, $\gamma_k$-sets and hyperspaces, Mathematica Balkanica 19, 109– 118, 2005.
  10. Lj.D.R. Kočinac, Selection principles and continuous images, Cubo Math. J. 8 (2), 23–31, 2006.
  11. S. Lin, C. Liu, and H. Teng, Fan tightness and strong Fréchet property of $C_k(X)$, Adv. Math. (Chinese) 23 (3), 234–237, 1994.
  12. G.Di Maio, Lj.D.R. Kočinac, and E. Meccariello, Applications of k-covers, Acta Math. Sin. (English Series) 22 (4), 1151–1160, 2006.
  13. G.Di Maio, Lj.D.R. Kočinac, and T. Nogura Convergence properties of hyperspaces, J. Korean Math. Soc. 44 (4), 845–854, 2007.
  14. A.J. Marsh, Topology of function spaces, Doctoral Dissertation, University of Pittsburgh, 2004.
  15. R.A. McCoy, Function spaces which are k-spaces, Topol. P. 5, 139–146, 1980.
  16. N. Noble, The density character of functions spaces, Proc. Amer. Math. Soc. 42, 228–233, 1974.
  17. A.V. Osipov, Different kinds of tightness of a funtional space, Tr. Inst. Mat. Mekh. (Russian), 22 (3), 192–199, 2016.
  18. A.V. Osipov, Application of selection principles in the study of the properties of function spaces, Acta Math. Hungar. 154 (2), 362–377, 2018.
  19. A.V. Osipov, Classification of selectors for sequences of dense sets of $C_p(X)$, Topology Appl. 242, 20–32, 2018.
  20. A.V. Osipov, The functional characterizations of the Rothberger and Menger properties, Topology Appl. 243, 146–152, 2018.
  21. A.V. Osipov, Classification of selectors for sequences of dense sets of Baire functions, submitted.
  22. A.V. Osipov and S. Özçağ, Variations of selective separability and tightness in function spaces with set-open topologies, Topology Appl. 217, 38–50, 2017.
  23. A.V. Osipov and E.G. Pytkeev, On sequential separability of functional spaces, Topology Appl. 221, 270–274, 2017.
  24. B.A. Pansera and V. Pavlović, Open covers and function spaces, Matematički Vesnik 58, 57–70, 2006.
  25. M. Sakai, k-Frechet-Urysohn Property of $C_k(X)$, Topol. App. 154 (7), 1516–1520, 2007.
  26. G. Tironi and R. Isler, On some problems of local approximability in compact spaces, In: General Topology and its Relations to Modern Analysis and Algebra III, 443–446, Prague, August 30-September 3, 1971, Academia, Prague, 1972.
  27. A. Wilansky, How separable is a space?, Amer. Math. Monthly 79 (7), 764–765, 1972.