arXiv math/05013652005-01math.AGmath.RT

Mirkovic-Vilonen cycles and polytopes

Joel Kamnitzer

备注：: 42 pages, v2: new sections added, references improved, mistakes corrected, exposition improved

英文摘要：

We give an explicit description of the Mirkovic-Vilonen cycles on the affine Grassmannian for arbitrary complex reductive groups. We also give a combinatorial characterization of the MV polytopes. We prove that a polytope is an MV polytope if and only if it a lattice polytope whose defining hyperplanes are parallel to those of the Weyl polytopes and whose 2-faces are rank 2 MV polytopes. As an application, we give a bijection between Lusztig's canonical basis and the set of MV polytopes.

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