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arXiv · 2605.28738

The Singer-Zauner gap for equiangular tight frames

Matthew Fickus·John Jasper·Dustin G. Mixon
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Abstract

We show that there does not exist a complex $d\times n$ equiangular tight frame with \[ d^2-d+1<n<d^2. \] The proof, which originated from an internal model at OpenAI, mimics the relationship between real equiangular tight frames and strongly regular graphs.

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Matthew Fickus, John Jasper, Dustin G. Mixon. 2026-05-27. The Singer-Zauner gap for equiangular tight frames. https://arxiv.org/abs/2605.28738

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