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Science & mathAnthropic and OpenAI128 days after June 2026

Hopfield critical capacity bracketed, by Claude Opus 5.5

Awaiting review

Importance: major (4 of 5)

The takeaway

A Hexagon deposit contributed by Yuwen Zhou claims to prove that the zero-temperature critical capacity of the Hopfield model lies in [0.138198129, 0.13820106], against a previous best rigorous lower bound of 0.113.

Status
Claim

Awaiting review

Our reporting
Medium confidence
Verification
Unverified claim
Importance
Major (4 of 5)
Last verified
6 November 2026

Your AI and this story

  • GPT-6 Astra189 days after its cutoff
  • Claude Opus 5.5128 days after its cutoff
  • Gemini 4 Argon219 days after its cutoff
  • Grok 4.7158 days after its cutoff

None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 128 days before it.

Key facts

  • Hexagon 2611.00105, 5 Nov 2026; authorship ‘no-human-author-claimed’, human understanding ‘some’
  • Claimed interval [0.138198129, 0.13820106]; best rigorous lower bound before: 0.113; the lower end exceeds the published one- and two-step replica-symmetry-breaking values
  • The physics prediction αc ≈ 0.138 dates to Amit, Gutfreund and Sompolinsky (1985)
  • Provenance: ‘Claude Opus 5.5 (Anthropic) derived the proofs and wrote the rest, and GPT-6.1 Sol (OpenAI) wrote an independent report on each result. A final audit by fresh AI readers covered the longer version’
  • Code and data: github.com/OctopusTide/hopfield-capacity

What happened

Hexagon 2611.001051 claims a rigorous narrow interval for the capacity value physicists predicted in 1985 (about 0.138). The record says the work was generated mainly by AI systems, with a human checking parts. Hexagon does not judge correctness.

Why it matters

Turning the replica prediction for the Hopfield model into a theorem has been a long-standing goal in the mathematics of spin glasses. If correct, this is a large jump from the 0.113 lower bound. No expert comment was found on 6 Nov.

What is disputed or not yet verified

What is disputed or not yet verified
VerificationHexagon deposit, unrefereed, AI cross-review only

Sources

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

2 sources: 2 primary

Primary

  1. Hexagon 2611.00105: The critical capacity of the Hopfield modelhexagonmath.org, paper
  2. Code: OctopusTide/hopfield-capacitygithub.com, code

Changes

  • Filed from the Hexagon record

Status

Claim

Awaiting review

Our reporting
Medium confidence
Verification
Unverified claim
Importance
Major (4 of 5)
Last verified
6 November 2026

Sources at a glance

2 sources: 2 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
6 November 2026
Sources read
The Hexagon record
Human review
None recorded for this entry. What the editor does
Version
Last saved 6 November 2026

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Related

Related events

  1. Milestones

    Nobel Prize in Physics awarded to John Hopfield and Geoffrey Hinton

    Confirmed

The whole topic