Abstract
Shokurov's vanishing theorem is used for the proof of the ℚ-factoriality of the following nodal threefolds: a complete intersection of hypersurfaces F and G in ℙ5 of degrees n and k, n ≥ k, such that G is smooth and |Sing(F ∩ G)| ≤ (n+k-2)(n-1)/5; a double cover of a smooth hypersurface F ⊃ ℙ4 of degree n branched over the surface cut on F by a hypersurface G ⊃ ℙ4 of degree 2r ≥ n, provided that |Sing(F ∩ G)| ≤ (2r + n - 2)r/4.
Original language | English |
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Pages (from-to) | 387-414 |
Number of pages | 28 |
Journal | Sbornik Mathematics |
Volume | 197 |
Issue number | 3-4 |
DOIs | |
Publication status | Published - 30 Apr 2006 |