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Outline

A tauberian theorem for distributional point values

2008, Archiv der Mathematik

https://doi.org/10.1007/S00013-008-2683-Z

Abstract

We give a tauberian theorem for boundary values of analytic functions. We prove that if f ∈ D (a, b) is the distributional limit of the analytic function F defined in a region of the form (a, b) × (0, R) , if F (x0 + iy) → γ as y → 0 + , and if f is distributionally bounded at x = x0, then f (x0) = γ distributionally. As a consequence of our tauberian theorem, we obtain a new proof of a tauberian theorem of Hardy and Littlewood.

Key takeaways
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AI

  1. The paper presents a tauberian theorem for distributional point values of analytic functions.
  2. It establishes that f(x0) = γ distributionally if f is bounded at x0.
  3. The theorem generalizes a classic result by Hardy and Littlewood.
  4. The proof leverages weak* convergence in L∞ and properties of bounded analytic functions.
  5. Applications include demonstrating convergence in series via tempered distributions.

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