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arXiv · 1402.2546

The Sasaki Join, Hamiltonian 2-forms, and Constant Scalar Curvature

Charles P. Boyer·Christina W. Tønnesen-Friedman
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Abstract

We describe a general procedure for constructing new Sasaki metrics of constant scalar curvature from old ones. Explicitly, we begin with a regular Sasaki metric of constant scalar curvature on a 2n+1-dimensional compact manifold M and construct a sequence, depending on four integer parameters, of rays of constant scalar curvature (CSC) Sasaki metrics on a compact Sasaki manifold of dimension $2n+3$. We also give examples which show that the CSC rays are often not unique on a fixed strictly pseudoconvex CR manifold or a fixed contact manifold. Moreover, it is shown that when the first Chern class of the contact bundle vanishes, there is a two dimensional subcone of Sasaki Ricci solitons in the Sasaki cone, and a unique Sasaki-Einstein metric in each of the two dimensional sub cones.

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Charles P. Boyer, Christina W. Tønnesen-Friedman. 2014-02-11. The Sasaki Join, Hamiltonian 2-forms, and Constant Scalar Curvature. https://arxiv.org/abs/1402.2546

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