The quasitopos hull of the construct of closure spaces


  • Veerle Claes Vrije Universiteit Brussel
  • G. Sonck Vrije Universiteit Brussel



Topological construct, Closure space, Extensional topological construct, Quasitopos, Cartesian closed category, Cartesian closed topological hull


In the list of convenience properties for topological constructs the property of being a quasitopos is one of the most interesting ones for investigations in function spaces, differential calculus, functional analysis, homotopy theory, etc. The topological construct Cls of closure spaces and continuous maps is not a quasitopos. In this article we give an explicit description of the quasitopos topological hull of Cls using a method of F. Schwarz: we first describe the extensional topological hull of Cls and of this hull we construct the cartesian closed topological hull.


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Author Biographies

Veerle Claes, Vrije Universiteit Brussel

Departement Wiskunde

G. Sonck, Vrije Universiteit Brussel

Departement Wiskunde


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How to Cite

V. Claes and G. Sonck, “The quasitopos hull of the construct of closure spaces”, Appl. Gen. Topol., vol. 4, no. 1, pp. 15–24, Apr. 2003.



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