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arXiv · 2308.15221

Morphisms between Grassmannians, II

Gianluca Occhetta·Eugenia Tondelli
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Abstract

Denote by $\mathbb G(k,n)$ the Grassmannian of linear subspaces of dimension $k$ in $\mathbb P^n$. We show that, if $\varphi:\mathbb G(l,n) \to \mathbb G(k,n)$ is a non constant morphism and $l \not=0,n-1$ then $l=k$ or $l=n-k-1$ and $\varphi$ is an isomorphism.

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Gianluca Occhetta, Eugenia Tondelli. 2023-08-29. Morphisms between Grassmannians, II. https://doi.org/10.1007/s00013-024-01986-y

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