2020/02/02 by Aleksy Tralle, Vicente Muñoz, Tralle, Aleksy +1 · 1 citation
Mathematics · #Geometric and Algebraic Topology #Geometry and complex manifolds #Geometric Analysis and Curvature Flows
paper · pdf · doi:10.48550/arxiv.2002.00457
Smale-Barden manifolds M are classified by their second homology H2(M,\mathbb Z) and the Barden invariant i(M). It is an important and dificult question to decide when M admits a Sasakian structure in terms of these data. In this work we show methods of doing this. In particular we realize all M with H2(M)=\mathbb Zk⊕(⊕i=1r\mathbb Zmi2gi) and i=0,∞, provided that k≥ 1, mi≥ 2, gi≥ 1, mi are pairwise coprime. Using our methods we also contribute to the problem of the existence of definite Sasakian structures on rational homology spheres. Also, we give a complete solution to the problem of the existence of Sasakian structures on rational homology spheres in the class of semi-regular Sasakian structures.