Fano double spaces of index two
نویسنده
چکیده
We study birational geometry of Fano varieties, realized as double covers σ: V → P M , M ≥ 5, branched over generic hypersurfaces W = W 2(M −1) of degree 2(M − 1). We prove that the only structures of a rationally connected fiber space on V are the pencils-subsystems of the free linear system | − 1 2 K V |. The groups of birational and biregular self-maps of the variety V coincide: Bir V = Aut V .
منابع مشابه
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تاریخ انتشار 2009