Source authenticated

Is block sensitivity at most quadratic in sensitivity? (Nisan-Szegedy)

Theorem 1.1: for every integer d≥1d\ge1 an explicit recursive construction gives a nonconstant total Boolean function with bs(f)/s(f)2≥2d/(4(d+2)2)\mathrm{bs}(f)/s(f)^2\ge2^d/(4(d+2)^2), so no bound bs≤Cs2\mathrm{bs}\le C s^2 holds; the abstract also claims a fixed α>2\alpha>2 with bs(f)≥s(f)α\mathrm{bs}(f)\ge s(f)^\alpha along an unbounded family. This does not close the gap to Huang's upper bound bs≤s4\mathrm{bs}\le s^4; the true exponent remains open. Because λ(f)≤s(f)\lambda(f)\le s(f), it also implies a negative answer to the spectral-sensitivity question bs=O(λ2)\mathrm{bs}=O(\lambda^2), which Meiburg had already disproved (see block-sensitivity-spectral-sensitivity-squared).

Exact FrontierDelta

Prior state unknown→disproved

Scope and record

Occurred: Sep 25, 2026

Delta type: SOURCE CLAIM

Assumptions: VibeMathed verification: lean-checked. Publication: announcement. AI contribution: ai-discovered. VibeMathed editorial classifications, scores, notes, relations, and dataset structure are CC BY 4.0. Source statements and linked content retain their own rights.

Canonical aliases: Is block sensitivity at most quadratic in sensitivity? (Nisan-Szegedy) · Quadratic sensitivity vs block sensitivity

Confidence: Not scored

Registry verification: lean checked · announcement · candidate

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Attribution

VibeMathed
registry · event recorded by

Unreleased internal OpenAI model
model · ai model contributor · OpenAI

Artifacts and verifiers

Lean proof (OAI.Paper320.quantitative_separation)

lean artifact · pending

Artifact ↗

Compute record

No linked compute attempts recorded.

Lineage and corrections

Nisan, Szegedy, On the degree of Boolean functions as real polynomials (1994) evidence for this event

VibeMathed record: Is block sensitivity at most quadratic in sensitivity? (Nisan-Szegedy) evidence for this event

This event attributed to Unreleased internal OpenAI model

Is block sensitivity at most quadratic in sensitivity? (Nisan-Szegedy) evidence for this event

Theorem 1.1: for every integer d≥1d\ge1 an explicit recursive construction gives a nonconstant total Boolean function with bs(f)/s(f)2≥2d/(4(d+2)2)\mathrm{bs}(f)/s(f)^2\ge2^d/(4(d+2)^2), so no bound bs≤Cs2\mathrm{bs}\le C s^2 holds; the abstract also claims a fixed α>2\alpha>2 with bs(f)≥s(f)α\mathrm{bs}(f)\ge s(f)^\alpha along an unbounded family. This does not close the gap to Huang's upper bound bs≤s4\mathrm{bs}\le s^4; the true exponent remains open. Because λ(f)≤s(f)\lambda(f)\le s(f), it also implies a negative answer to the spectral-sensitivity question bs=O(λ2)\mathrm{bs}=O(\lambda^2), which Meiburg had already disproved (see block-sensitivity-spectral-sensitivity-squared). parent of this event

Lean proof (OAI.Paper320.quantitative_separation) evidence for this event

Meiburg, Block sensitivity can exceed spectral sensitivity squared (arXiv:2608.00851), the construction this adapts evidence for this event

Is block sensitivity at most quadratic in sensitivity? (Nisan-Szegedy) parent of this event

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