Rationality and Chow–künneth Decompositions for Some Moduli Stacks of Curves
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چکیده
In this paper we show the existence of a Chow–Künneth decomposition for the moduli stack of stable curves with marked points Mg,r, for low values of g, r. We also look at the moduli space R3,2 of double covers of genus three curves, branched along 4 distinct points. We first obtain a birational model of R3,2 as a group quotient of a product of two Grassmannian varieties. This provides a Chow–Künneth decomposition over an open subset of R3,2. The question of rationalilty of R3,2 is also discussed.
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تاریخ انتشار 2009