Se p 20 01 Homogeneous Spaces , Tits Buildings , and Isoparametric Hypersurfaces
نویسنده
چکیده
We classify 1-connected compact homogeneous spaces which have the same rational cohomology as a product of spheres S1 × S2 , with 3 ≤ n1 ≤ n2 and n2 odd. As an application, we classify compact generalized quadrangles (buildings of type C2) which admit a point transitive automorphism group, and isoparametric hypersurfaces which admit a transitive isometry group on one focal manifold. Received by the editor February 22, 2001. 1991 Mathematics Subject Classification. Primary 51H, 53C; Secondary 51E12, 57T15.
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