Czechoslovak Mathematical Journal, Vol. 70, No. 2, pp. 299-310, 2020


On real flag manifolds with cup-length equal to its dimension

Marko Radovanović

Received June 14, 2018.   Published online November 18, 2019.

Abstract:  We prove that for any positive integers $n_1,n_2,\ldots,n_k$ there exists a real flag manifold $F(1,\ldots,1,n_1,n_2,\ldots,n_k)$ with cup-length equal to its dimension. Additionally, we give a necessary condition that an arbitrary real flag manifold needs to satisfy in order to have cup-length equal to its dimension.
Keywords:  cup-length; flag manifold; Lyusternik-Shnirel'man category
Classification MSC:  14M15, 55M30, 57N65


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Affiliations:   Marko Radovanović, University of Belgrade, Faculty of Mathematics, Studentski trg 16, Belgrade, Serbia, e-mail: markor@matf.bg.ac.rs


 
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