HIGHER SECANT VARIETIES OF P n × P m EMBEDDED IN BI - DEGREE (
نویسندگان
چکیده
Let X (n,m) (1,d) denote the Segre-Veronese embedding of Pn×Pm via the sections of the sheaf O(1, d). We study the dimensions of higher secant varieties of X (n,m) (1,d) and we prove that there is no defective sth secant variety, except possibly for n values of s. Moreover when (m+d d ) is a multiple of (m+ n+ 1), the sth secant variety of X (n,m) (1,d) has the expected dimension for every s.
منابع مشابه
Secant Varieties of Segre-Veronese Varieties Pm × Pn Embedded by O(1, 2)
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