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A Topological sphere theorem for contact CR-warped product submanifolds of an odd-dimensional unit sphere

  • Fulya Şahin and Bayram Şahin EMAIL logo
Published/Copyright: June 11, 2022
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Abstract

In this paper, we investigate topological sphere theorems for compact minimal contact CR-submanifolds of odd dimensional unit sphere. We show that if an inequality involving the warping function and the scalar curvature of the fibers is satisfied, a compact minimal contact CR-warped product submanifold of the odd dimensional unit sphere is homeomorphic to the sphere. In particular case, for 5-dimensional unit sphere, we show that a 4-dimensional compact minimal contact CR-warped product submanifold is homeomorphic to a sphere if ∣∇ln f2 < 1 is satisfied. By using Bonnet-Myers’s theorem we give a result about fundamental group and by Leung’s theorem we obtain a result about homology groups of a contact CR-warped submanifold.


This work was supported by Research Fund of the Ege University Grant No.20776.



bayram.sahin@ege.edu.tr


  1. (Communicated by Július Korbaš)

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Received: 2021-04-03
Accepted: 2021-06-08
Published Online: 2022-06-11
Published in Print: 2022-06-27

© 2022 Mathematical Institute Slovak Academy of Sciences

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