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Fibrewise separation axioms for locales

Published online by Cambridge University Press:  24 October 2008

P. T. Johnstone
Affiliation:
Department of Pure Mathematics, University of Cambridge, 16 Mill Lane, Cambridge CB2 1SB

Abstract

In this paper we study the weak versions of the fibrewise separation axioms for locales over a base locale, whose introduction has been made possible by the development, in a previous paper by the author, of the fibrewise notion of closure for sublocales of locales over a base. We establish the implications which hold between these axioms and the traditional separation axioms for locales, and give counter-examples to show that some of these implications are irreversible.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1990

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References

REFERENCES

[1]Isbell, J. R.. Atomless parts of spaces. Math. Scand. 31 (1972), 532.CrossRefGoogle Scholar
[2]Isbell, J. R.. Function spaces and adjoints. Math. Scand. 36 (1975), 317339.CrossRefGoogle Scholar
[3]Isbell, J. R.. Product spaces in locales. Proc. Amer. Math. Soc. 81 (1981), 116118.Google Scholar
[4]Isbell, J. R.. Review of [12]. Bull. Amer. Math. Soc. (N.S.) 11 (1984), 389392.Google Scholar
[5]Isbell, J. R.. First steps in descriptive theory of locales. Preprint, August 1989.Google Scholar
[6]James, I. M.. General Topology and Homotopy Theory (Springer-Verlag, 1984).Google Scholar
[7]James, I. M.. Spaces. Bull. Land. Math. Soc. 18 (1986), 529559.CrossRefGoogle Scholar
[8]James, I. M.. Fibrewise Topology (Cambridge University Press, 1989).Google Scholar
[9]Jibladze, M. and Johnstone, P. T.. The frame of fibrewise closed nuclei. Cahiers Topologie Géom. Différentielle Catégoriques. (Submitted.)Google Scholar
[10]Johnstone, P. T.. The Gleason cover of a topos, II. J. Pure Appl. Alg. 22 (1981), 229247.Google Scholar
[11]Johnstone, P. T.. The point of pointless topology. Bull. Amer. Math. Soc. (N.S.) 8 (1983), 4153.CrossRefGoogle Scholar
[12]Johnstone, P. T.. Stone Spaces. Cambridge Studies in Advanced Math. no. 3 (Cambridge University Press, 1983).Google Scholar
[13]Johnstone, P. T.. Open locales and exponentiation. In Mathematical Applications of Category Theory, Contemp. Math. vol. 30 (American Mathematical Society, 1984), pp. 84116.Google Scholar
[14]Johnstone, P. T.. A constructive ‘closed subgroup theorem’ for localic groups and groupoids. Cahiers Topologie Géom. Différentielle Catégoriques 30 (1989), 323.Google Scholar
[15]Johnstone, P. T.. A constructive theory of uniform locales. (Submitted.)Google Scholar
[16]Murchiston, G. S. and Stanley, M. G.. A ‘T 1’ space with no closed points, and a “T 1” locale which is not ‘T 1. Math. Proc. Cambridge Philos. Soc. 95 (1984), 421422.CrossRefGoogle Scholar
[17]Niefield, S. B.. Cartesian spaces over T and locales over Ω(T). Cahiers Topologie Géom. Différentielle Catégoriques 23 (1982), 257267.Google Scholar
[18]Pultr, A.. Pointless uniformities, I: complete regularity. Comment. Math. Univ. Carolin. 25 (1984), 91104.Google Scholar
[19]Simmons, H.. Spaces with Boolean assemblies. Colloq. Math. 43 (1980), 2329.Google Scholar