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Eric Peterson
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When does the conormal bundle sequence split?

Let $X\subset \mathbb{P}^n$ be a smooth projective variety with ideal sheaf $I_X$. The conormal sequence is given by

$$ 0\to I_X/I_X^2\to \Omega_{\mathbb{P}^n}|_X\to \Omega_{X}\to 0. $$ For which varieties $X$ is the sequence above split?

If I'm not mistaken, if $X$ a hypersurface, the sequence is split if and only if $X$ has degree 1.

J.C. Ottem
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