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arXiv · 1503.02245

Rings with each right ideal automorphism-invariant

M. Tamer Koşan·Truong Cong Quynh·Ashish K. Srivastava
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Abstract

In this paper, we study rings having the property that every right ideal is automorphism-invariant. Such rings are called right $a$-rings. It is shown that (1) a right $a$-ring is a direct sum of a square-full semisimple artinian ring and a right square-free ring, (2) a ring $R$ is semisimple artinian if and only if the matrix ring $\mathbb{M}_n(R)$ for some $n>1$ is a right $a$-ring, (3) every right $a$-ring is stably-finite, (4) a right $a$-ring is von Neumann regular if and only if it is semiprime, and (5) a prime right $a$-ring is simple artinian. We also describe the structure of an indecomposable right artinian right non-singular right $a$-ring as a triangular matrix ring of certain block matrices.

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M. Tamer Koşan, Truong Cong Quynh, Ashish K. Srivastava. 2015-03-08. Rings with each right ideal automorphism-invariant. https://arxiv.org/abs/1503.02245

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