Dimension formulas for spaces of vector-valued Siegel modular forms of degree two and level two

Jonas Bergström; Fabien Cléry

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arXiv · 2309.04388

Dimension formulas for spaces of vector-valued Siegel modular forms of degree two and level two

Jonas Bergström·Fabien Cléry

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Abstract

Using a description of the cohomology of local systems on the moduli space of abelian surfaces with a full level two structure, together with a computation of Euler characteristics we find the isotypical decomposition, under the symmetric group on 6 letters, of spaces of vector-valued Siegel modular forms of degree two and level two.

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Jonas Bergström, Fabien Cléry. 2023-09-08. Dimension formulas for spaces of vector-valued Siegel modular forms of degree two and level two. https://arxiv.org/abs/2309.04388

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