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arXiv · 2312.09849

On The Equivariant Tamagawa Number Conjecture

Samit Dasgupta·Mahesh Kakde·Jesse Silliman
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Abstract

Let $F$ be a totally real field and $K$ a finite abelian CM extension of $F$. Using class field theory, we show that our previous result giving a strong form of the Brumer-Stark conjecture implies the minus part of the equivariant Tamagawa number conjecture for the Tate motive associated to $K/F$. We work integrally over $\mathbf{Z}$, in particular the prime 2 is not inverted. This note can be viewed as our perspective on the recent work of Bullach, Burns, Daoud, and Seo. Following their philosophy, we show that the functorial properties (i.e. norm compatibilities) connecting the strong Brumer-Stark conjecture for varying number fields actually implies the minus part of the equivariant Tamagawa number conjecture.

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Samit Dasgupta, Mahesh Kakde, Jesse Silliman. 2023-12-15. On The Equivariant Tamagawa Number Conjecture. https://arxiv.org/abs/2312.09849

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