Affine stratification of 𝒜₄

Atyam, Anant

doi:10.1090/proc/12525

Affine stratification of $\mathcal {A}_4$
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Proc. Amer. Math. Soc. 143 (2015), 4167-4175

Abstract:

We construct an affine stratification for $\mathcal {A}_4(\mathbb {C})$ of length 6, in the sense of Roth and Vakil (2004), which gives us an upper bound of 6 for the cohomological dimension of $\mathcal {A}_4(\mathbb {C})$. We conjecture that, in general, for arbitrary $g$, the cohomological dimension of $\mathcal {A}_g$ is equal to $g(g-1)/2$.

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