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Topological Fundamental Groups and Small Generated Coverings

  • Hamid Torabi EMAIL logo , Ali Pakdaman and Behrooz Mashayekhy
Published/Copyright: December 9, 2015
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Mathematica Slovaca
From the journal Mathematica Slovaca Volume 65 Issue 5

Abstract

This paper is devoted to study some topological properties of the SG subgroup, πsg1 (X, x), of the quasitopological fundamental group of a based space (X, x), πqtop1 (X, x), its topological properties as a subgroup of the topological fundamental group πτ1 (X, x) and its influence on the existence of universal covering of X. First, we introduce small generated spaces which have indiscrete topological fundamental groups and also small generated coverings which are universal coverings in the categorical sense. Second, we give a necessary and sufficient condition for the existence of the small generated coverings. Finally, by introducing the notion of semi-locally small generatedness we show that the quasitopological fundamental groups of semi-locally small generated spaces are topological groups.

Keywords: quasitopological fundamental group; topological fundamental group; SG subgroup; small generated covering; semi-locally small generated space

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Received: 2012-4-12
Accepted: 2012-12-6
Published Online: 2015-12-9
Published in Print: 2015-10-1

Mathematical Institute Slovak Academy of Sciences

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  1. Finite Mixed Sums wih Harmonic Terms
  2. Packing of ℝ2 by Crosses
  3. On the Integrality of the Elementary Symmetric Functions of 1, 1/3, . . . , 1/(2n − 1)
  4. Generalized Derivations as a Generalization of Jordan Homomorphisms Acting on Lie Ideals and Right Ideals
  5. Generalized Derivations on Lie Ideals and Power Values on Prime Rings
  6. On Monoids of Injective Partial Cofinite Selfmaps
  7. Extensions of Dynamic Inequalities of Hardy’s Type on Time Scales
  8. The Controlled Convergence Theorem for the Gap-Integral
  9. The Solvability of a Nonlocal Boundary Value Problem
  10. Oscillation Criteria for Third Order Differential Equations with Functional Arguments
  11. Asymptotic Behavior of Solutions of a Nonlinear Neutral Generalized Pantograph Equation with Impulses
  12. On Null Lagrangians
  13. Principal Eigenvalues for Systems of Schrödinger Equations Defined in the whole Space with Indefinite Weights
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  16. Representation of Extendible Bilinear Forms
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  19. A Relation between two Kinds of Norms for Martingales
  20. Linearization Regions in Singular Weakly Nonlinear Regression Models with Constraints
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https://doi.org/10.1515/ms-2015-0079
Keywords for this article
quasitopological fundamental group; topological fundamental group; SG subgroup; small generated covering; semi-locally small generated space

Articles in the same Issue

  1. Finite Mixed Sums wih Harmonic Terms
  2. Packing of ℝ2 by Crosses
  3. On the Integrality of the Elementary Symmetric Functions of 1, 1/3, . . . , 1/(2n − 1)
  4. Generalized Derivations as a Generalization of Jordan Homomorphisms Acting on Lie Ideals and Right Ideals
  5. Generalized Derivations on Lie Ideals and Power Values on Prime Rings
  6. On Monoids of Injective Partial Cofinite Selfmaps
  7. Extensions of Dynamic Inequalities of Hardy’s Type on Time Scales
  8. The Controlled Convergence Theorem for the Gap-Integral
  9. The Solvability of a Nonlocal Boundary Value Problem
  10. Oscillation Criteria for Third Order Differential Equations with Functional Arguments
  11. Asymptotic Behavior of Solutions of a Nonlinear Neutral Generalized Pantograph Equation with Impulses
  12. On Null Lagrangians
  13. Principal Eigenvalues for Systems of Schrödinger Equations Defined in the whole Space with Indefinite Weights
  14. Convergence of Series on Large Set of Indices
  15. On Approximation Properties of a New Type of Bernstein-Durrmeyer Operators
  16. Representation of Extendible Bilinear Forms
  17. Spectra and Fine Spectra of Lower Triangular Double-Band Matrices as Operators on Lp (1 ≤ p < ∞)
  18. Topological Fundamental Groups and Small Generated Coverings
  19. A Relation between two Kinds of Norms for Martingales
  20. Linearization Regions in Singular Weakly Nonlinear Regression Models with Constraints
  21. Parametric Equilibrium Problems Governed by Topologically Pseudomonotone Bifunctions
  22. Identification of a Parameter in Fourth-Order Partial Differential Equations by an Equation Error Approach
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