On the Quadratic Normality and the Triple Curve of Three Dimensional Subvarieties of P
نویسنده
چکیده
A well-known conjecture asserts that smooth threefolds X ⊂ P5 are quadratically normal with the only exception of the Palatini scroll. As a corollary of a more general statement we obtain the following result, which is related to the previous conjecture: If X ⊂ P5 is not quadratically normal, then its triple curve is reducible.
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