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تسجيل مستخدم جديدEquivariant compactifications of vector groups with high index
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In this note, we classify smooth equivariant compactifications of $mathbb{G}_a^n$ which are Fano manifolds with index $geq n-2$.
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Let $G$ be a simple complex algebraic group, $P$ a parabolic subgroup of $G$ and $N$ the unipotent radical of $P.$ The so-called equivariant compactification of $N$ by $G/P$ is given by an action of $N$ on $G/P$ with a dense open orbit isomorphic to
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