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Michel Brion; Baohua Fu
Minimal rational curves on wonderful group compactifications
(Courbes rationnelles minimales sur les compactifications magnifiques des groupes)
Journal de l'École polytechnique — Mathématiques, 2 (2015), p. 153-170, doi: 10.5802/jep.20
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Class. Math.: 14L30, 14M27, 20G20
Mots clés: Courbes rationnelles minimales, compactifications magnifiques

Résumé - Abstract

Soient $G$ un groupe algébrique simple et $X$ sa compactification magnifique. Nous montrons que $X$ possède une unique famille de courbes rationnelles minimales, et nous décrivons explicitement la sous-famille formée des courbes passant par un point général. Nous en déduisons une propriété de rigidité de $X$, lorsque $G$ n’est pas de type $A_1$ ou $C$.

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