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arXiv · 2302.12332

On the Root of Unity Ambiguity in a Formula for the Brumer--Stark Units

Matthew H. L. Honnor
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Abstract

We prove a conjectural formula for the Brumer--Stark units. Dasgupta--Kakde have shown the formula is correct up to a bounded root of unity. In this paper we resolve the ambiguity in their result. We also remove an assumption from Dasgupta--Kakde's result on the formula.

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Matthew H. L. Honnor. 2023-02-23. On the Root of Unity Ambiguity in a Formula for the Brumer--Stark Units. https://arxiv.org/abs/2302.12332

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