Abstract
We give an “integration by parts” approach to Davies’ Hardy inequality. An improvement with a strictly larger Hardy weight is thereby obtained.
Notes
See, e.g., Lemma on p. 169 of Reed and Simon’s book [12].
In terms of Hardy weights: \(\frac{n}{4\widetilde m(x)^2}>\frac{n}{4 m(x)^2}\).
It also holds for unbounded intervals like \((-\infty,b)\) and \((a,\infty)\), but not for \(\mathbb{R}\).
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Acknowledgments
The author wishes to thank Dr. Georgios Psaradakis for his constructive criticism on “reproofs” of classical inequalities.
Funding
Research of the author is supported by the National NSF grant of China (no. 11801274). This paper was completed while the author was on a visit, funded by CSC Postdoctoral/Visiting Scholar Program (no. 202006865011), at LAGA of Université Sorbonne Paris Nord.
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Translated from Funktsional'nyi Analiz i ego Prilozheniya, 2023, Vol. 57, pp. 104–107 https://doi.org/10.4213/faa4042.
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Huang, Y.C. A Remark on Davies’ Hardy Inequality. Funct Anal Its Appl 57, 83–86 (2023). https://doi.org/10.1134/S0016266323010100
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DOI: https://doi.org/10.1134/S0016266323010100