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arXiv · 1710.05492

Surjections of unit groups and semi-inverses

Justin Chen
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Abstract

Given a surjective ring homomorphism, we study when the induced group homomorphism on unit groups is surjective. To this end, we introduce notions of generalized inverses and units, as well as a class of rings such that the set of closed points in the spectrum is a closed set. It is shown that any surjection out of such a ring induces a surjection on unit groups.

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Justin Chen. 2017-10-16. Surjections of unit groups and semi-inverses. https://arxiv.org/abs/1710.05492

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