On point-finiteness in pointfree topology

• Author(s): Ferreira, Maria João ; Picado, Jorge
• Date: 2006
• Persistent ID: http://hdl.handle.net/10316/11341
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Frame; Locale; Sublocale lattice; Congruence lattice; Cover; Interiorpreserving cover; Closure-preserving cover; Closure-preserving cover; Point-finite cover; Locally finite cover
• Document Type: Preprint
• Language: English

Description

In pointfree topology, the point-finite covers introduced by Dowker and Strauss do not behave similarly to their classical counterparts with respect to transitive quasi-uniformities, contrarily to what happens with other familiar types of interior-preserving covers. The purpose of this paper is to remedy this by modifying the definition of Dowker and Strauss. We present arguments to justify that this modification turns out to be the right pointfree definition of point-finiteness. Along the way we place point-finite covers among the classes of interior-preserving and closure-preserving families of covers that are relevant for the theory of (transitive) quasi-uniformities, completing the study initiated with [6]. Centro de Matemática da Universidade de Coimbra; Fundação para a Ciência e Tecnologia