Läuchli's completeness theorem from a topos-theoretic perspective

We prove a variant of Läuchli's completeness theorem for intuitionistic predicate calculus. The formulation of the result relies on the observation (due to Lawvere) that Läuchli's theorem is related to the logic of the canonical indexing of the atomic topos of ℤ-sets. We show that the proc...

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Detalles Bibliográficos
Autor: Menni, Matías
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/120204
Acceso en línea:http://hdl.handle.net/11336/120204
Access Level:acceso abierto
Palabra clave:LÄUCHLI'S COMPLETENESS THEOREM
TOPOS THEORY
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:We prove a variant of Läuchli's completeness theorem for intuitionistic predicate calculus. The formulation of the result relies on the observation (due to Lawvere) that Läuchli's theorem is related to the logic of the canonical indexing of the atomic topos of ℤ-sets. We show that the process that transforms Kripke-counter-models into Läuchli-counter-models is (essentially) the inverse image of a geometric morphism. Completeness follows because this geometric morphism is an open surjection.