Abstract
The aim of this note is to show that certain number theoretic inequalities, due to Nesbitt and Shapiro, have noncommutative counterparts involving positive definite matrices.
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Acknowledgements
We thank Apoorva Khare for a detailed reading of an earlier draft and for providing valuable comments and feedback. We also thank anonymous referees for their helpful comments. P. N. Choudhury is supported by National Post-Doctoral Fellowship (PDF/2019/000275), from SERB, Government of India. K. C. Sivakumar acknowledges funds received from MATRICS (MTR/2018/001132) of SERB, Government of India.
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Communicated by Qingxiang Xu.
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Choudhury, P.N., Sivakumar, K.C. Nesbitt and Shapiro cyclic sum inequalities for positive definite matrices. Adv. Oper. Theory 7, 7 (2022). https://doi.org/10.1007/s43036-021-00171-0
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DOI: https://doi.org/10.1007/s43036-021-00171-0
Keywords
- Positive definite matrices
- Trace inequality
- Eigenvalue inequality
- Nesbitt’s inequality
- Shapiro’s inequality