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The dimension of the Hilbert scheme of special threefolds

GianMario Besana·Maria Lucia Fania
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Abstract

The Hilbert scheme of projective 3-folds of codimension 3 or more that are linear scrolls over the projective plane or over a smooth quadric surface or that are quadric or cubic fibrations over the projective line is studied. All known such threefolds of degree from 7 to 11 are shown to correspond to smooth points of an irreducible component of their Hilbert scheme, whose dimension is computed. A relationship with the locus of good determinantal subschemes is investigated

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GianMario Besana, Maria Lucia Fania. 2004-12-06. The dimension of the Hilbert scheme of special threefolds. https://arxiv.org/abs/math/0412117

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