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Quadratic Varieties of Small Codimension (2405.04002v3)
Published 7 May 2024 in math.AG, math.CV, and math.DG
Abstract: Let $X \subset \mathbb{P}{n+c}$ be a nondegenerate smooth projective variety of dimension $n$ defined by quadratic equations. For such varieties, P. Ionescu and F. Russo proved the Hartshorne conjecture on complete intersections, which states that $X$ is a complete intersection provided that $n \geq 2c+1$. As the extremal case, they also classified $X$ with $n=2c$. In this paper, we classify $X$ with $n=2c-1$.
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