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The K-Theory of Heegaard-Type Quantum 3-Spheres

Paul Baum·Piotr M. Hajac·Rainer Matthes·Wojciech Szymanski
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Abstract

We use a Heegaard splitting of the topological 3-sphere as a guiding principle to construct a family of its noncommutative deformations. The main technical point is an identification of the universal C*-algebras defining our quantum 3-spheres with an appropriate fiber product of crossed-product C*-algebras. Then we employ this result to show that the K-groups of our family of noncommutative 3-spheres coincide with their classical counterparts.

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Paul Baum, Piotr M. Hajac, Rainer Matthes, Wojciech Szymanski. 2004-12-28. The K-Theory of Heegaard-Type Quantum 3-Spheres. https://arxiv.org/abs/math/0409573

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