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On the ideals of Secant Varieties to certain rational varieties

M. V. Catalisano·A. V. Geramita·A. Gimigliano
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Abstract

If $\X \subset ¶^n$ is a reduced and irreducible projective variety, it is interesting to find the equations describing the (higher) secant varieties of $\X$. In this paper we find those equations in the following cases: $\X = ¶^{n_1}\times...\times¶^{n_t}\times¶^n$ is the Segre embedding of the product and $n$ is "large" with respect to the $n_i$ (Theorem 2.4); $\X$ is a Segre-Veronese embedding of some products with 2 or three factors; $\X$ is a Del Pezzo surface.

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M. V. Catalisano, A. V. Geramita, A. Gimigliano. 2006-09-06. On the ideals of Secant Varieties to certain rational varieties. https://arxiv.org/abs/math/0609054

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