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Torsion in K0 of unit-regular rings*

Published online by Cambridge University Press:  20 January 2009

K. R. Goodearl
K. R. Goodearl
Affiliation:
Department of Mathematics, University of California, Santa Barbara, CA 93106, U.S.A.
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Abstract

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We construct examples of unit-regular rings R for which K0(R) has torsion, thus answering a longstanding open question in the negative. In fact, arbitrary countable torsion abelian groups are embedded in K0 of simple unit-regular algebras over arbitrary countable fields. In contrast, in all these examples K0(R) is strictly unperforated.

Type
Research Article
Information
Proceedings of the Edinburgh Mathematical Society , Volume 38 , Issue 2 , June 1995 , pp. 331 - 341
Copyright
Copyright © Edinburgh Mathematical Society 1995

References

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