Insertion of continuous real functions on spaces, bispaces, ordered spaces and ...

• Author(s): Ferreira, Maria João ; Gutiérrez García, Javier ; Picado, Jorge
• Date: 2009
• Persistent ID: http://hdl.handle.net/10316/11191
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Frame; Locale; Localic real function; Insertion theorem; Biframe; Normal biframe; Extremally disconnected biframe; Bitopological space; Ordered topological space
• Document Type: Preprint
• Language: English

Description

We characterize normal and extremally disconnected biframes in terms of the insertion of a continuous real function in between given lower and upper semicontinuous real functions and show this to be the common root of several classical and new insertion results concerning topological spaces, bitopological spaces, ordered topological spaces and locales. Centre of Mathematics of the University of Coimbra/FCT; Ministry of Education and Science of Spain and FEDER under grant MTM2006-14925-C02-02; University of the Basque Country under grant GIU07/27.