Univalent Functions in Hardy Spaces in Terms of the Growth of Arc-Length
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Abstract
Pommerenke (1962) proved that for f univalent in the unit disk and 0<p<2, f∈H p if and only if ∫ 0 1 M 1 p (r,f′)dr<∞. In this paper, we prove that the result continues to be true for p slightly larger than 2, but is false for large p. Also, it turns out that the result is true for all p>0 when f is restricted to the class of close-to-convex functions. Finally, we discuss the membership of univalent functions in some related spaces of Dirichlet type.
Keywords
Univalent functions Hardy spaces Integral means Arc-length Dirichlet type spacesMathematics Subject Classification (2000)
30C55 30D55 46E15Preview
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References
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