Hurwitz spaces of triple coverings of elliptic curves and moduli spaces of abelian threefolds

Vassil Kanev

doi:10.1007/s10231-003-0098-9

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Hurwitz spaces of triple coverings of elliptic curves and moduli spaces of abelian threefolds

Vassil Kanev

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Abstract

We prove that the moduli spaces A_3(D) of polarized abelian threefolds with polarizations of types D=(1,1,2), (1,2,2), (1,1,3) or (1,3,3) are unirational. The result is based on the study of families of simple coverings of elliptic curves of degree 2 or 3 and on the study of the corresponding period mappings associated with holomorphic differentials with trace 0. In particular we prove the unirationality of the Hurwitz space H_{3,A}(Y) which parameterizes simply branched triple coverings of an elliptic curve Y with determinants of the Tschirnhausen modules isomorphic to A^{-1}.

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Vassil Kanev. 2003-08-03. Hurwitz spaces of triple coverings of elliptic curves and moduli spaces of abelian threefolds. https://doi.org/10.1007/s10231-003-0098-9

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