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JOURNAL OF
ALGEBRAIC
COMBINATORICS

  Editors-in-chief: C. A. Athanasiadis, T. Lam, A. Munemasa, H. Van Maldeghem
ISSN 0925-9899 (print) • ISSN 1572-9192 (electronic)
 

A GKM description of the equivariant cohomology ring of a homogeneous space

V. Guillemin1 , T. Holm2 and C. Zara2
1Department of Mathematics, MIT, Cambridge, MA 02139
2Department of Mathematics, Penn State Altoona, PA, 16601

DOI: 10.1007/s10801-006-6027-4

Abstract

Let T be a torus of dimension n > 1 and M a compact T-manifold. M is a GKM manifold if the set of zero dimensional orbits in the orbit space M/ T is zero dimensional and the set of one dimensional orbits in M/ T is one dimensional. For such a manifold these sets of orbits have the structure of a labelled graph and it is known that a lot of topological information about M is encoded in this graph.
In this paper we prove that every compact homogeneous space M of non-zero Euler characteristic is of GKM type and show that the graph associated with M encodes geometric information about M as well as topological information. For example, from this graph one can detect whether M admits an invariant complex structure or an invariant almost complex structure.

Pages: 21–41

Keywords: keywords GKM graph; homogeneous spaces; equivariant cohomology

Full Text: PDF

References

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