Derivatives at the boundary for analytic Lipschitz functions
Sbornik. Mathematics, Tome 207 (2016) no. 10, pp. 1471-1490 Cet article a éte moissonné depuis la source Math-Net.Ru

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We consider the behaviour of holomorphic functions on a bounded open subset of the plane, satisfying a Lipschitz condition with exponent $\alpha$, with $0<\alpha<1$, in the vicinity of an exceptional boundary point where all such functions exhibit some kind of smoothness. Specifically, we consider the relation between the abstract idea of a bounded point derivation on the algebra of such functions and the classical complex derivative evaluated as a limit of difference quotients. We show that whenever such a bounded point derivation exists at a boundary point $b$, it may be evaluated by taking a limit of classical difference quotients, approaching from a set having full area density at $b$. Bibliography: 13 titles.
Keywords: analytic function, boundary, Lipschitz condition, point derivation, difference quotient, capacity
Mots-clés : Hausdorff content.
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A. G. O'Farrell. Derivatives at the boundary for analytic Lipschitz functions. Sbornik. Mathematics, Tome 207 (2016) no. 10, pp. 1471-1490. http://geodesic.mathdoc.fr/item/SM_2016_207_10_a7/

[1] D. H. Armitage, S. J. Gardiner, Classical potential theory, Springer Monogr. Math., Springer-Verlag London, Ltd., London, 2001, xvi+333 pp. | MR | Zbl

[2] A. Browder, Introduction to function algebras, W. A. Benjamin, Inc., New York–Amsterdam, 1969, xii+273 pp. | MR | Zbl

[3] E. P. Dolzhenko, “O “stiranii” osobennostei analiticheskikh funktsii”, UMN, 18:4(112) (1963), 135–142 | MR | Zbl

[4] H. Federer, Geometric measure theory, Grundlehren Math. Wiss., 153, Springer-Verlag, New York, 1969, xiv+676 pp. | MR | MR | Zbl | Zbl

[5] L. Hörmander, The analysis of linear partial differential operators, v. I, Grundlehren Math. Wiss., 256, Distribution theory and Fourier analysis, Springer-Verlag, Berlin, 1998, ix+391 pp. | DOI | MR | MR | Zbl | Zbl

[6] D. J. Lord, A. G. O'Farrell, “Boundary smoothness properties of Lip $\alpha$ analytic functions”, J. Anal. Math., 63:1 (1994), 103–119 | DOI | Zbl

[7] Y. Mizuta, Potential theory in Euclidean spaces, GAKUTO Internat. Ser. Math. Sci. Appl., 6, Gakkōtosho Co., Ltd., Tokyo, 1995, viii+341 pp. | MR | Zbl

[8] A. G. O'Farrell, “Equiconvergence of derivations”, Pacific J. Math., 53:2 (1974), 539–554 | DOI | MR | Zbl

[9] A. G. O'Farrell, “Analytic capacity, Hölder conditions, and $\tau$-spikes”, Trans. Amer. Math. Soc., 196 (1974), 415–424 | DOI | MR | Zbl

[10] A. G. O'Farrell, “Annihilators of rational modules”, J. Functional Analysis, 19:4 (1975), 373–389 | DOI | MR | Zbl

[11] A. G. O'Farrell, “Boundary smoothness of analytic functions”, Anal. Math. Phys., 4:1-2 (2014), 131–144 | DOI | MR | Zbl

[12] D. R. Sherbert, “The structure of ideals and point derivations in Banach algebras of Lipschitz functions”, Trans. Amer. Math. Soc., 111 (1964), 240–272 | DOI | MR | Zbl

[13] L. Schwartz, Théorie des distributions, Publ. Inst. Math. Univ. Strasbourg, IX-X, Nouvelle ed., entierement corr., refondue et augm., Hermann, Paris, 1966, xiii+420 pp. | MR | Zbl