%0 Journal Article
%T The cone of effective one-cycles of certain G-varieties
%A Michel Brion
%J Mathematics
%D 2002
%I arXiv
%X 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.
%U http://arxiv.org/abs/math/0211027v1