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arXiv · 2107.02305

Equivariant Chow-Witt groups and moduli stacks of elliptic curves

Andrea Di Lorenzo·Lorenzo Mantovani
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Abstract

We introduce equivariant Chow-Witt groups in order to define Chow-Witt groups of quotient stacks. We compute the Chow-Witt ring of the moduli stack of stable (resp. smooth) elliptic curves, providing a geometric interpretation of the new generators. Along the way, we also determine the Chow-Witt ring of the classifying stack of $\mu_{2n}$.

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Andrea Di Lorenzo, Lorenzo Mantovani. 2021-07-05. Equivariant Chow-Witt groups and moduli stacks of elliptic curves. https://arxiv.org/abs/2107.02305

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