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arXiv · 2006.08454

Pseudo-Sylvester domains and skew Laurent polynomials over firs

Fabian Henneke·Diego López-Álvarez
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Abstract

Building on recent work of Jaikin-Zapirain, we provide a homological criterion for a ring to be a pseudo-Sylvester domain, that is, to admit a division ring of fractions over which all stably full matrices become invertible. We use the criterion to study skew Laurent polynomial rings over free ideal rings (firs). As an application of our methods, we prove that crossed products of division rings with free-by-{infinite cyclic} and surface groups are pseudo-Sylvester domains unconditionally and Sylvester domains if and only if they admit stably free cancellation. This relies on the recent proof of the Farrell--Jones conjecture for normally poly-free groups and extends previous results of Linnell--L\"uck and Jaikin-Zapirain on universal localizations and universal fields of fractions of such crossed products.

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Fabian Henneke, Diego López-Álvarez. 2020-06-15. Pseudo-Sylvester domains and skew Laurent polynomials over firs. https://arxiv.org/abs/2006.08454

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