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arXiv · 1501.00787

On Lie nilpotent rings and Cohen's Theorem

Jeno Szigeti·Leon van Wyk
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Abstract

We study certain (two-sided) nil ideals and nilpotent ideals in a Lie nilpotent ring R. Our results lead us to showing that the prime radical rad(R) of R comprises the nilpotent elements of R, and that if L is a left ideal of R, then L+rad(R) is a two-sided ideal of R. This in turn leads to a Lie nilpotent version of Cohen's theorem, namely if R is a Lie nilpotent ring and every prime (two-sided) ideal of R is finitely generated as a left ideal, then every left ideal of R containing the prime radical of R is finitely generated (as a left ideal). For an arbitrary ring R with identity we also consider its so-called n-th Lie center Z_n(R), which is a Lie nilpotent ring of index n. We prove that if C is a commutative submonoid of the multiplicative monoid of R, then the subring of R generated by the union of Z_n(R) and C is also Lie nilpotent of index n.

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Jeno Szigeti, Leon van Wyk. 2015-01-05. On Lie nilpotent rings and Cohen's Theorem. https://arxiv.org/abs/1501.00787

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