Fourier frames for odd-base Cantor measures

The question is whether for every odd integer base b>1, the fair {0,2} base-b Cantor measure admits no Fourier frame. The middle-third case answers Strichartz’s question.

Why it matters and what counts as progress

Why it matters: It asks whether Fourier exponentials can form a stable frame for the middle-third and other odd-base Cantor measures.

What counts as progress: Prove Fourier-frame nonexistence for the stated Cantor measures, or identify a change of base, weights or digit set that permits a frame.

How the problem developed

  1. 1998 · Foundational result [1][2]

    Palle Jorgensen and Steen Pedersen Constructed Fourier bases for certain Cantor measures and showed that the middle-third Cantor measure has no Fourier basis; this left open whether it admits a Fourier frame.

  2. 2000 · Open question [2][3]

    Robert S. Strichartz Raised the question whether the middle-third Cantor measure admits a Fourier frame.

  3. 9 Jul 2026 · Reported theorem [4]

    Jaume de Dios Pont, Lukas Liehr and Mitchell A. Taylor Claimed that no odd-integer-base Cantor measure admits a Fourier frame, including the middle-third case.

AI contribution

Cantor measures with odd base do not admit Fourier frames

Jaume de Dios Pont, Lukas Liehr, Mitchell A. Taylor

For every odd integer base b>1, the fair {0,2} base-b Cantor measure admits no Fourier frame. The middle-third case answers Strichartz’s question.

Paper date:

Sources

  1. Palle Jorgensen and Steen Pedersen · Orthogonal harmonic analysis of fractal measures
  2. Robert S. Strichartz · Mock Fourier series and transforms associated with certain Cantor measures
  3. D. E. Dutkay, D. Han and Q. Sun · Weighted Fourier frames on self-affine measures
  4. Jaume de Dios Pont, Lukas Liehr and Mitchell A. Taylor · Cantor measures with odd base do not admit Fourier frames
  5. Cantor measures with odd base do not admit Fourier frames
  6. Cantor-frame formalization and review
  7. Independent Walsh-quotient proof
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