Prym varieties of pairs of coverings
نویسندگان
چکیده
The Prym variety of a pair of coverings is defined roughly speaking as the complement of the Prym variety of one morphism in the Prym variety of another morphism. We show that this definition is symmetric and give conditions when such a Prym variety is isogenous to an ordinary Prym variety or to another such Prym variety. Moreover in order to show that these varieties actually occur we compute the isogeny decomposition of the Jacobian variety of a curve with an action of the symmetric group S5.
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Algebraic description of Jacobians isogeneous to certain Prym varieties with polarization (1,2)∗
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