Abstract
We prove some optimal logarithmic estimates in the Hardy space H ∞(G) with Hölder regularity, where G is the open unit disk or an annular domain of ℂ. These estimates extend the results established by S.Chaabane and I.Feki in the Hardy-Sobolev space H k,∞ of the unit disk and those of I. Feki in the case of an annular domain. The proofs are based on a variant of Hardy-Landau-Littlewood inequality for Hölder functions. As an application of these estimates, we study the stability of both the Cauchy problem for the Laplace operator and the Robin inverse problem.
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This research has been supported by the Laboratory of Applied Mathematics and Harmonic Analysis: L.A.M.H.A. LR 11ES52
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Chaabane, S., Feki, I. Pointwise inequalities of logarithmic type in Hardy-Hölder spaces. Czech Math J 64, 351–363 (2014). https://doi.org/10.1007/s10587-014-0106-9
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DOI: https://doi.org/10.1007/s10587-014-0106-9
Keywords
- Hardy-Sobolev space
- Hardy-Landau-Littlewood inequality
- Hölder regularity
- Cauchy problem
- inverse problem
- logarithmic estimate