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Science & mathOpenAI36 days after June 2026

Sendov’s 1958 conjecture on polynomial roots proved with GPT-5.6 Pro

Tao simplifies and formalises it

Result confirmed

Importance: major (4 of 5)

The takeaway

Lech Mazur posted a computer-assisted proof, generated with GPT-5.6 Pro, of Sendov’s conjecture for all degrees: if every root of a polynomial lies in the closed unit disk, each root is within distance 1 of a critical point.

Status
Claim

Result confirmed

Our reporting
High confidence
Verification
Lean-verified
Importance
Major (4 of 5)
Last verified
19 October 2026

Your AI and this story

  • GPT-6 Astra97 days after its cutoff
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None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 36 days before it.

Key facts

  • Conjecture from 1958; previously known for degree < 9 (Brown–Xiang) and for sufficiently large degree (Tao, 2020)
  • Mazur’s preprint 5 Aug 2026 (some lists say 3 Aug); Tao’s digestion 12 Aug 2026
  • Tao extended the method to the Phelps–Rodriguez conjecture

What happened

A non-academic used GPT-5.6 Pro to generate a computer-assisted proof covering the remaining degrees. Tao then digested it into a short argument based on the fundamental theorem of algebra and the Maclaurin inequality.

Why it matters

It is a classic, well-known conjecture closed by AI, with the leading expert on the problem verifying and formalising the result.

Sources

2 sources from 2 sites. Numbers match the chips in the text.

2 sources: 1 primary, 1 reaction

Primary

  1. Lech Mazur: Sendov conjecture proof (PDF)proofatlas.ai, paper

Reactions

  1. Terence Tao: A digestion of the proof of Sendov’s conjectureterrytao.wordpress.com, discussion

Changes

  • Related: back-link to Lech Mazur’s Collatz result (same author and ProofAtlas harness)
  • Filed

Status

Claim

Result confirmed

Our reporting
High confidence
Verification
Lean-verified
Importance
Major (4 of 5)
Last verified
19 October 2026

Sources at a glance

2 sources: 1 primary, 1 reaction

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 September 2026
Human review
None recorded for this entry. What the editor does
Version
Last saved 19 October 2026

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People in this story

Terence Tao, Professor of mathematics, UCLA

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