Continuous fields of interval algebras
Laurent Cantier
TL;DR
The paper addresses the classification of one-parameter continuous fields of unital AI-algebras by extending Cuntz semigroup methods to the field setting. It develops a local-to-global framework that combines Michael's selection theorem with a novel gluing technique to lift fiberwise Cu-data to continuous-field morphisms, and introduces a field version of the Cu-category to obtain a functorial viewpoint. For a natural inductive-limit class $\mathcal{C}$ built from $C([0,1])$ tensored with unital interval algebras, the authors prove existence and uniqueness results for morphisms, and show that Cu-isomorphisms descending to fibers lift to field isomorphisms, yielding a Cu-based classification (CP). The work thus provides a constructive, fiber-aware Cu-classification in the AI-interval regime and lays groundwork for a Cu-functorial framework of continuous fields, with potential to distinguish and relate such fields via field-level invariants.
Abstract
This paper investigates and classifies a specific class of one-parameter continuous fields of C*-algebras, which can be seen as generalized AI-algebras. Building on the classification of *-homomorphisms between interval algebras by the Cuntz semigroup, along with a selection theorem and a gluing procedure, we employ a 'local-to-global' strategy to achieve our classification result.
