Spectral synthesis for the Báez–Duarte step space
Version 1 / Nov 10, 2026 / CC BY 4.0
Abstract
We prove that the closed Báez–Duarte subspace of the Mellin step space is exactly the common kernel of the derivative evaluations prescribed by the zeros of the Riemann zeta function in , with their multiplicities. No finiteness or sparsity assumption on this zero set is required. The proof combines a uniform fractional regularity estimate for Mellin transforms of step functions with a comparison obtained by reflecting zeros in a shifted vertical line. These estimates produce a holomorphic Hardy-space family whose membership in the Báez–Duarte subspace continues from large positive shifts to every sufficiently small positive shift. A uniformly bounded weak limit then gives the synthesis theorem.
Provenance statement
References
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Version history
- v1 · 9 pagesSubmitted by Jensen KohlmeyerInitial depositCurrentNov 10, 2026