On the theories classified by an étendue

2025/07/06 by Wrigley, Joshua
#03C50 (Secondary) #03G30 (Primary) 18F10 #18B25 #Category Theory (math.CT) #FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2507.04526

Abstract

We give a model-theoretic characterisation of the geometric theories classified by étendues -- the `locally localic' topoi. They are the theories where each model is determined, syntactically and semantically, by any witness of a fixed collection of formulae.

Citations

• On topological groupoids that represent theories
• Generalising the étale groupoid--complete pseudogroup correspondence
• Non-commutative Stone duality: inverse semigroups, topological groupoids\n and C*-algebras
• A non-commutative generalization of Stone duality

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