论文信息 - Proper maps of locales

Proper maps of locales

Abstract We investigate the basic properties of stably closed, or proper maps of locales, in a setting formally similar to that developed by A. Joyal and M. Tierney for treating the descent theory of localic open maps. We show that proper maps are precisely the compact (perfect) maps previously considered by P.T. Johnstone, and that proper surjections are stable coequalizers, effective for descent in the category of locales.

J.J.C. Vermeulen | J. Vermeulen

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