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Science China Mathematics

, Volume 62, Issue 5, pp 935–960 | Cite as

On a class of almost regular Landsberg metrics

  • Shasha Zhou
  • Jiayue Wang
  • Benling LiEmail author
Articles
  • 27 Downloads

Abstract

There is a long existing ıicorn" problem in Finsler geometry: whether or not any Landsberg metric is a Berwald metric? Some classes of metrics were studied in the past and no regular non-Berwaldian Landsberg metric was found. However, if the metric is almost regular (allowed to be singular in some directions), some non-Berwaldian Landsberg metrics were found in the past years. All of them are composed by Riemannian metrics and 1-forms. This motivates us to find more almost regular non-Berwaldian Landsberg metrics in the class of general (α,β)-metrics. In this paper, we first classify almost regular Landsberg general (α,β)-metrics into three cases and prove that those regular metrics must be Berwald metrics. By solving some nonlinear PDEs, some new almost regular Landsberg metrics are constructed which have not been described before.

Keywords

Finsler metric Landsberg metric Berwald metric (α,β)-metric 

MSC(2010)

53B40 53C60 

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Notes

Acknowledgements

This work was supported by Zhejiang Provincial Natural Science Foundation of China (ZPNSFC) (Grant No. R18A010002), National Natural Science Foundation of China (Grant No. 11371209) and K.C. Wong Magna Fund in Ningbo University. The authors thank the referees for their helpful comments.

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Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of MathematicsNingbo UniversityNingboChina

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