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On the classification of defective threefolds

L. Chiantini·C. Ciliberto
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Abstract

We classify all irreducible projective threefolds $X$ which are $k$-defective, i.e. some $k$-secant variety of $X$ has dimension less than the expected value. This results extends the classical Scorza's classification of the case $k=1$.

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L. Chiantini, C. Ciliberto. 2004-06-18. On the classification of defective threefolds. https://arxiv.org/abs/math/0312518

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