Corpus ID: 235742875

The topology of Gelfand-Zeitlin fibers

  title={The topology of Gelfand-Zeitlin fibers},
  author={Jeffrey D. Carlson and Jeremy Lane},
We prove several new results about the topology of fibers of Gelfand–Zeitlin systems on unitary and orthogonal coadjoint orbits. First, we provide a simplified description of their diffeomorphism types as balanced products, recovering results of Bouloc–Miranda–Zung as special cases. Second, we compute their cohomology rings. Finally, we complete the computation of their first three homotopy groups (the first and second homotopy groups were described by Cho–Kim–Oh in the unitary case). Our… Expand

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