Bulletin of the Korean Mathematical Society (대한수학회보)

Korean Mathematical Society (대한수학회)
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INTEGRABILITY OF AN ALMOST COMPLEX STRUCTURE ON S4 × fV2

  • Cho, Jong Taek (Department of Mathematics Chonnam National University) ;
  • Chun, Sun Hyang (Department of Mathematics Chosun University) ;
  • Euh, Yunhee (Department of Mathematics Chonnam National University)
  • Received : 2020.07.15
  • Accepted : 2022.05.09
  • Published : 2022.07.31
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Abstract

In this paper, we prove that any orthogonal almost complex structure on a warped product manifold of any oriented closed surface and a round 4-sphere for a concircular warping function on the sphere is never integrable. This gives a partial answer to Calabi's problem.

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Acknowledgement

The authors would like to thank the referee for carefully reading the manuscript and for valuable comments to improve it.

References

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