Kraetzer’s universal integral-means spectrum formula
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For normalized univalent disk maps, determine the p=−1 universal integral-means spectrum. The counterexample target is a uniform M_−1[f′](r)≤C(1−r)^(−1/4+ε), ε>0, implying B_b(−1)<1/4 for the bounded-image spectrum.
Why it matters and what counts as progress
Why it matters: A strict bound below one quarter would contradict the predicted spectrum formula at this exponent.
What counts as progress: A strict improvement below the predicted p=−1 spectrum value, or a corrected universal integral-means formula.
How the problem developed
- 1996 · Conjecture [1]
P. Kraetzer Proposed the quadratic formula for the universal integral-means spectrum on |p|≤2, based on computer experiments.
- 24 Sept 2026 · Counterexample to prediction [2]
OpenAI research team Proved B_b(−1)<1/4, contradicting the predicted value at p=−1.
- 16 Oct 2026 · Stronger bound [3]
Ilia Binder, Oleg Ivrii, István Prause and Stanislav Smirnov Reported B_b(t)≤t²/4 on [−2,2], with strict inequality in the interior except at zero, while noting that details of the strictness argument are deferred.
AI contribution
A strict inverse-first-power bound for univalent functions
For normalized univalent disk maps, OpenAI proves M_{−1}[f′](r)≤C(1−r)^(−1/4+ε) for some ε>0 and all 1/2≤r<1. Thus the bounded-image universal spectrum B_b(−1)<1/4.
Sources
- P. Kraetzer, Experimental bounds for the universal integral means spectrum of conformal maps
- OpenAI, Kraetzer's conjecture on the universal integral means spectrum
- Ilia Binder et al., Brennan’s Conjecture and the Universal Integral Means Spectrum
- A strict inverse-first-power bound for univalent functions
- Lean proof of OpenAI reports a strict bound that refutes Kraetzer’s spectrum formula
- OpenAI mathematics release and provenance
- OpenAI, Brennan’s conjecture and sharp inverse-square integral means
Website timeline
Publication dates and editorial changes.
OpenAI reports a strict bound that refutes Kraetzer’s spectrum formula