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arXiv · 2501.15993

Isomorphism and stable isomorphism in "real" and "quaternionic" K-theory

Malkhaz Bakuradze·Ralf Meyer
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Abstract

We find lower bounds on the rank of a "real" vector bundle over an involutive space, such that "real" vector bundles of higher rank have a trivial summand and such that a stable isomorphism for such bundles implies ordinary isomorphism. We prove similar lower bounds also for "quaternionic" bundles. These estimates have consequences for the classification of topological insulators with time-reversal symmetry.

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Malkhaz Bakuradze, Ralf Meyer. 2025-01-27. Isomorphism and stable isomorphism in "real" and "quaternionic" K-theory. https://arxiv.org/abs/2501.15993

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