DeepMind says its AI agents ran a four-day cryptography test with about 20 human messages

Google DeepMind says two AI agents reproduced a known 1024-bit cryptography computation over nearly four days with about 20 human messages, mostly approvals, carrying the research through coding, large-scale execution and debugging.

The test concerns RSA digital signatures. After billions of advance queries to a simulated signing service, the agents computed a mathematical root needed for a new signature once access ended. They did not recover a private key.

The working paper reports 391 CPU core-years for the completed computation, compared with an earlier team's rounded 1,380 on the same instance and algorithm. That is about a 3.5-fold reduction in measured CPU use. GPU work and preliminary probes are excluded.

DeepMind researcher @pushmeet announced the work on Nov. 6, describing a sandboxed reproduction of a previously solved benchmark instance. The papers say these results do not threaten deployed cryptosystems based on 2048-bit or larger RSA.

The human chose the problem, instance and limits on the signing service, then approved conditions for irreversible steps. According to the paper, the researcher wrote no code, launched no jobs and diagnosed no faults.

A supervisor agent maintained the design, budgets and checks. An executor wrote and tested code, launched distributed jobs and repaired failures. The supervisor also enlisted a specialist sub-agent to accelerate one linear-algebra step.

The agents produced about 33,500 new lines of code, ran 336 distributed experiments and exchanged 218 messages. From design to the verified result, the work took three days and 22 hours.

Their first computed root was wrong because a 32-bit offset overflowed. A correctness check caught the error, and the agents located and fixed it without repeating the advance signing queries. Limited human messaging still came with a human-selected task and approval gates.

What the speedup measures

The earlier academic computation took about five months. DeepMind's run took 3.2 days from its first full-scale sieving job to the verified root, reaching about 300,000 CPU cores and 16 GPUs at peak. The authors attribute that calendar-time difference mainly to parallelism.

The CPU saving arose from implementation and execution changes within the existing algorithm. The 391-core-year total excludes about 330 reserved GPU-hours, of which about 100 were busy, and 7.5 core-years of probes and rehearsals. The CPU totals also come from different hardware, so this is not a controlled like-for-like comparison.

The cryptographic setup also matters: a separate program holding the modulus factorization answered roughly 4 billion advance queries. It was withdrawn before the target was drawn. The agents then computed the target's root without further queries.

The measured reproduction did not demonstrate the paper's new algorithm for more restricted signing access at cryptographic size. A separate Fan Factories paper estimates roughly 30-fold lower costs per additional 1024-bit target than the multiple number field sieve, after shared precomputation costing about one general number field sieve factorization. These are leading-order heuristic estimates; no fan factory has been implemented.

The working paper identifies the principal models only as A and B and links no public implementation repository, limiting outside comparisons.