ON THE CONCEPT OF k-SECANT ORDER OF A VARIETY
نویسندگان
چکیده
For a variety X of dimension n in Pr, r n(k + 1) + k, the kth secant order of X is the number μk(X) of (k + 1)-secant k-spaces passing through a general point of the kth secant variety. We show that, if r > n(k + 1) + k, then μk(X) = 1 unless X is k-weakly defective. Furthermore we give a complete classification of surfaces X ⊂ Pr, r > 3k + 2, for which μk(X) > 1.
منابع مشابه
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