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arXiv · 2406.06780

Bijections Between Sets of Invariant Ideals, Via the Ladder Technique

Matthew Gillespie·S. Kaliszewski·John Quigg·Dana P. Williams
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Abstract

We present a new method of establishing a bijective correspondence - in fact, a lattice isomorphism - between action- and coaction-invariant ideals of C*-algebras and their crossed products by a fixed locally compact group. It is known that such a correspondence exists whenever the group is amenable; our results hold for any locally compact group under a natural form of coaction invariance.

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Matthew Gillespie, S. Kaliszewski, John Quigg, Dana P. Williams. 2024-06-10. Bijections Between Sets of Invariant Ideals, Via the Ladder Technique. https://arxiv.org/abs/2406.06780

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