Double Cubics and Double Quartics

نویسنده

  • IVAN CHELTSOV
چکیده

In this paper we study a double cover ψ : X → V ⊂ P branched over a smooth divisor S ⊂ V such that n ≥ 7, the degree of V is 3 or 4, and S is cut on the hypersurface V by a hypersurface of degree 2(n− deg(V )). The variety X is rationally connected, because it is a smooth Fano variety. We prove that X is birationally superrigid. In particular, the variety X is nonrational.

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تاریخ انتشار 2004