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arXiv · 2508.14396

Strongly clean ring elements that are one-sided inverses

George M. Bergman
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Abstract

A longstanding open question is whether every strongly clean ring (ring in which every element is strongly clean, i.e., is the sum of an idempotent and a unit which commute with each other) is Dedekind-finite (has the property that every element with a one-sided inverse is invertible). We give an example of a ring with two strongly clean elements that are one-sided, but not two-sided, inverses of one another, suggesting that the answer to that question may be negative. We then discuss possible ways of strengthening this result to give a full negative answer. We end with some brief observations on related topics, in particular, uniquely strongly clean rings.

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George M. Bergman. 2025-08-20. Strongly clean ring elements that are one-sided inverses. https://arxiv.org/abs/2508.14396

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