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Science & mathCzech Academy of Sciences99 days after June 2026

Open-source multi-agent system run unattended on about 3,800 open problems from research papers; about 200 reported solved, four STOC 2026 questions confirmed by the papers’ authors

Awaiting review

The takeaway

A Prague group pointed an open-source prover–verifier loop built on GPT-5.5 and GPT-5.6 Sol at every open question it could extract from recent papers, with no per-problem human guidance. It reports about 214 solutions out of 3,800 attempts, most of them estimates, and four results that the authors of STOC 2026 papers confirmed.

Status
Claim

Awaiting review

Our reporting
Medium confidence
Verification
Expert-checked
Importance
3 of 5
Last verified
13 October 2026

Your AI and this story

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None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 99 days before it.

Key facts

  • Paper: ‘Bolzano: From Expert-Guided Proof Search to Automated Open-Problem Solving’, arXiv 2610.09769 [cs.AI], 7 Oct 2026 (v2 9 Oct); ‘Accepted at the 6th Workshop on Mathematical Reasoning and AI (MATH-AI), NeurIPS 2026’
  • Table 1 (problems / model / rounds / promising / solved): arXiv math.CO and cs.DS 1,600 / GPT-5.5 / 4 / 250 / 90; STOC 2026 420 / GPT-5.5 / 4 / 41 / 4; earlier FOCS, SODA and STOC 900 / GPT-5.6 Sol / 2 / 57 / 40; Midsummer Combinatorial Workshop 880 / GPT-5.6 Sol / 2 / 137 / 80; total 3,800 / 485 / 214
  • Caveat (Table 1 footnote): ‘Except for STOC 2026, the solved counts are estimates. These estimates are partially informed by LLM-based assessments of whether the output addresses the source question and whether its argument is substantially correct.’ For STOC 2026 only the four results checked by the team and verified by the source papers’ authors are counted
  • Setup: ‘the prover, verifier, and summarizer operated without web search, code execution, direct filesystem access, or any tools’; all runs used one prover at the maximum reasoning effort; open problems were extracted from the papers by a separate LLM workflow with literature search
  • STOC 2026 results, confirmed ‘in private correspondence in June and July 2026’: a one-pass O(log n)-memory algorithm detecting a semi-random planted biclique with sides at least Cn^(2/3) (question from Garg, Hastings, Pabbaraju and Sharan); an exponential separation between monotone rank programs and monotone span programs (Cavalar et al.); a strongly convex rational quartic in two variables whose zero sublevel set is a single irrational point (Slot, Steurer and Wiedmer); an Ω(log n) circuit-depth lower bound for joining and splitting biased CAT states (Parham)
  • Footnote: for the convex-quartic and CAT-state results ‘the authors reviewed only the main idea, not the full proof’
  • Paper: ‘Bolzano found a few hundred solutions, which we sent to authors of the source papers, some of whom plan to include these results in revised versions of their papers.’
  • Limits stated by the authors: ‘The verifier is another LLM, not a formal proof checker. An accepted but incorrect lemma may propagate through persistent memory’; observed failures ‘include missing assumptions, proofs addressing weaker versions of the original questions, invalid arguments and rediscoveries of known results’; there is ‘no comparison with direct use of the underlying models’
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  • Earlier report: ‘Bolzano: Case studies in LLM-assisted mathematical research’, arXiv 2604.16989 (eight problems checked by domain experts; six classed as publishable research and five as essentially autonomous). Project site: bolzano.app

What happened

Bolzano is an open-source system from Charles University in Prague. In each round several prover agents attack a problem in parallel, a verifier agent criticises their output and updates three shared documents (notes, candidate proofs, current outcome), and a summarizer records the round. A first report in April 2026 described eight results obtained with expert guidance and checked by specialists.

The new paper asks whether the same loop works with nobody steering. An LLM workflow read four collections of papers (new arXiv submissions in combinatorics and algorithms, papers accepted to STOC 2026, older FOCS/SODA/STOC papers, and work around the Midsummer Combinatorial Workshop), extracted every explicitly stated open question, checked that it was still open, and wrote a self-contained task. Each task got a fixed budget of two or four rounds with GPT-5.5 or GPT-5.6 Sol and no tools. The team then screened the outputs, compared promising ones with the original question and sent a few hundred to the authors of the source papers.

The headline number, “about 200 open problems”, is an estimate. The firmly checked part is the STOC 2026 experiment: four answers that the papers’ own authors confirmed, among them an algorithm matching a known memory lower bound up to logarithmic factors and an exponential separation between two models of monotone computation.

Why it matters

OpenAI’s October release of 722 manuscripts came from an internal model and its own problem list. Bolzano is a public, open-source pipeline built on commercially available models by a university group, and it took its problems from other people’s papers, whose authors could check the answers. The paper is also frank about the bottleneck it exposes: producing candidate solutions is cheap, and judging their correctness, scope and novelty is now the expensive step.

What is disputed or not yet verified

What is disputed or not yet verified
VerificationFour STOC 2026 results confirmed by source-paper authors in private correspondence (two only at the level of the main idea); the other counts are estimates partly based on LLM audits; workshop paper

The four STOC results were not checked against the source papers, and the confirmations are private correspondence reported by the authors. bolzano.app and the code repository were not inspected. No press coverage or Hacker News discussion was found on 13 Oct 2026.

Sources

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

3 sources: 3 primary

Primary

  1. arXiv 2610.09769: Bolzano: From Expert-Guided Proof Search to Automated Open-Problem Solvingarxiv.org, paper
  2. arXiv 2604.16989: Bolzano: Case studies in LLM-assisted mathematical researcharxiv.org, paper
  3. Bolzano project sitebolzano.app, official

Changes

  • Filed from the arXiv PDF (v2)

Status

Claim

Awaiting review

Our reporting
Medium confidence
Verification
Expert-checked
Importance
3 of 5
Last verified
13 October 2026

Sources at a glance

3 sources: 3 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
13 October 2026
Sources read
The arXiv PDF (v2)
Human review
None recorded for this entry. What the editor does
Version
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