SBI ring
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In algebra, an SBI ring is a type of ring R (with identity) such that every idempotent of R modulo the Jacobson radical can be lifted to R. The abbreviation SBI was introduced by Irving Kaplansky and stands for "suitable for building idempotent elements".
Definition
Examples
- Any ring with nil radical is SBI.
- Any Banach algebra is SBI: more generally, so is any compact topological ring.
- The ring of rational numbers with odd denominator is not SBI.
Citations
- Jacobson, Nathan (1956), Structure of rings, American Mathematical Society, Colloquium Publications, vol. 37, Providence, R.I.: American Mathematical Society, ISBN 978-0-8218-1037-8, MR , Zbl
{{citation}}:ISBN / Date incompatibility (help) - Kaplansky, Irving (1972), Fields and Rings, Chicago Lectures in Mathematics (2nd ed.), University Of Chicago Press, pp. 124–125, ISBN 0-226-42451-0, Zbl