Abstract
Let G be the product GL r (C) × (C ×)n. We show that the G-equivariant Chow class of a G orbit closure in the space of r-by-n matrices is determined by a matroid. To do this, we split the natural surjective map from the G equvariant Chow ring of the space of matrices to the torus equivariant Chow ring of the Grassmannian. The splitting takes the class of a Schubert variety to the corresponding factorial Schur polynomial, and also has the property that the class of a subvariety of the Grassmannian is mapped to the class of the closure of those matrices whose row span is in the variety.
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21 April 2021
A Correction to this paper has been published: https://doi.org/10.1007/s00031-021-09651-2
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BERGET, A., FINK, A. EQUIVARIANT CHOW CLASSES OF MATRIX ORBIT CLOSURES. Transformation Groups 22, 631–643 (2017). https://doi.org/10.1007/s00031-016-9406-5
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DOI: https://doi.org/10.1007/s00031-016-9406-5