A tauberian theorem for distributional point values
2008, Archiv der Mathematik
https://doi.org/10.1007/S00013-008-2683-ZAbstract
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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- The paper presents a tauberian theorem for distributional point values of analytic functions.
- It establishes that f(x0) = γ distributionally if f is bounded at x0.
- The theorem generalizes a classic result by Hardy and Littlewood.
- The proof leverages weak* convergence in L∞ and properties of bounded analytic functions.
- Applications include demonstrating convergence in series via tempered distributions.
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