Relative regular modules. Applications to von Neumann regular rings

Leonard Daus

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arXiv · 0803.1285

Relative regular modules. Applications to von Neumann regular rings

Leonard Daus

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Abstract

We use the concept of a regular object with respect to another object in an arbitrary category, defined in \cite{dntd}, in order to obtain the transfer of regularity in the sense of Zelmanowitz between the categories $R-$mod and $S-$mod, when $S$ is an excellent extension of the ring $R$. Consequently, we obtain a result of \cite{ps}: if $S$ is an excellent extension of the ring $R$, then $S$ is von Neumann regular ring if and only if $R$ is also von Neumann regular ring. In the second part, using relative regular modules, we give a new proof of a classical result: the von Neumann regular property of a ring is Morita invariant. Finally, the von Neumann regularity of the Morita ring is investigated.

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Leonard Daus. 2008-03-09. Relative regular modules. Applications to von Neumann regular rings. https://arxiv.org/abs/0803.1285

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