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arXiv · 1311.4683

Sums of units in function fields II - The extension problem

Christopher Frei
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Abstract

In 2007, Jarden and Narkiewicz raised the following question: Is it true that each algebraic number field has a finite extension L such that the ring of integers of L is generated by its units (as a ring)? In this article, we answer the analogous question in the function field case. More precisely, it is shown that for every finite non-empty set S of places of an algebraic function field F | K over a perfect field K, there exists a finite extension F' | F, such that the integral closure of the ring of S-integers of F in F' is generated by its units (as a ring).

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Christopher Frei. 2013-11-19. Sums of units in function fields II - The extension problem. https://doi.org/10.4064/aa149-4-5

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