Abstract
Having as starting point Barr's description of topological spaces as lax algebras for the ultrafilter monad, in this paper we present further topological examples of lax algebras – such as quasi-metric spaces, approach spaces and quasi-uniform spaces – and show that, in a suitable setting, the categories of lax algebras have indeed a topological nature. Furthermore, we generalize to this setting known properties of special categories of lax algebras and, extending the construction of Manes, we describe the Čech–Stone compactification of lax algebras.
Similar content being viewed by others
References
Adámek, J., Herrlich, H. and Strecker, G. E.: Abstract and Concrete Categories, Wiley Interscience, New York, 1990.
Barr, M.: Relational algebras, in Springer Lecture Notes in Math. 137, 1970, pp. 39–55.
Clementino, M. M. and Hofmann, D.: Triquotient maps via ultrafilter convergence, Proceedings of the American Mathematical Society 130 (2002), 3423–3431.
Clementino, M. M., Hofmann, D. and Tholen, W.: One setting for all: Metric, topology, uniformity, approach structure, in preparation.
Clementino, M. M., Hofmann, D. and Tholen, W.: The convergence approach to exponentiable maps, Portugaliae Mathematica 60 (2003), 139–159.
Freyd, P. J. and Scedrov, A.: Categories, Allegories, North-Holland Mathematical Library, Elsevier Science Publishers B.V., 1990.
Isbell, J.: Uniform Spaces, Math. Surveys 12, American Mathematical Society, 1964.
Johnstone, P. T.: Stone Spaces, Cambridge Studied in Advanced Mathematics 3, Cambridge University Press, Cambridge, 1982.
Lawvere, F. W.: Metric spaces, generalized logic, and closed categories, Rendiconti del Seminario Matematico e Fisico di Milano 43 (1973), 135–166.
Lowen, R.: Approach Spaces: The Missing Link in the Topology-Uniformity-Metric Triad, Oxford Mathematical Monographs, Oxford University Press, Oxford, 1997.
Mac Lane, S.: Categories for the Working Mathematician, 2nd edn, Springer, New York, 1998.
Manes, E. G.: Compact Hausdorff objects, Topology and its Applications 4 (1974), 341–360.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Clementino, M.M., Hofmann, D. Topological Features of Lax Algebras. Applied Categorical Structures 11, 267–286 (2003). https://doi.org/10.1023/A:1024274315778
Issue Date:
DOI: https://doi.org/10.1023/A:1024274315778