The Cone of Effective One–cycles of Certain G–varieties
نویسنده
چکیده
Let X be a normal projective variety admitting an action of a semisimple group with a unique closed orbit. We construct finitely many rational curves in X , all having a common point, such that every effective one–cycle on X is rationally equivalent to a unique linear combination of these curves with non–negative rational coefficients. When X is nonsingular, these curves are projective lines, and they generate the integral Chow group of one–cycles. To C. S. Seshadri for his 70th birthday
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