
International Relations & AI. @aigioxford Within DPhil @Politics_Oxford. Former @hdx. Not here often. Find me at https://xitter.cf/t.co/XOTH3Zrv4C
Oxford, UK
Joined March 2009
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Ben Harack retweeted
We're recruiting PhD (DPhil) students at @UniofOxford to tackle some of the most important open problems in technical AI safety and governance!
In our Technical Safety & Governance (TSG) Lab, we're particularly interested in developing methods to better understand, evaluate and control advanced AI systems.
Some of the research directions we're excited about include:
Training models to explain themselves and other models: Can we train AI systems to provide explanations that help humans and other AI systems better understand, predict and oversee their behaviour?
Understanding and controlling how model behaviours emerge during training: Can we predict undesirable behaviours from early training checkpoints and intervene before they emerge?
These are just examples of the broader research questions we're excited about. We're open to other ambitious and original ideas in related areas, so don't feel limited to the specific approaches outlined.
There are also exciting research opportunities across AIGI, including projects led by fellow lab directors pro @maosbot on Bayesian governance and Prof. Amro Awad on hardware governance.
Who should apply?
If you have a strong technical background in machine learning, computer science, mathematics, or related fields, and are excited about pursuing ambitious research that could help make advanced AI systems safer, we'd love to hear from you.
I am committed to partnering with researchers from disadvantage and under represented backgrounds.
How to apply:
Explore the example projects, identify a research direction that interests you, and contact the relevant lab director to discuss your ideas. Your application should clearly address at least one of the AIGI labs.
📅 Deadline: 2 December 2026 (Direct DPhil route)
Please share with talented students and researchers who might be interested!
#PhD #AISafety #AIGovernance #Oxford #AIGI
Ben Harack retweeted
Btw if attention here was allocated in an insight-tracking way this should get something between 100k to 0.5M view.
I think the discourse about this chart (which is afaik the source of this "only 7% of compute goes to pretraining now" number going around) is confused in a few ways, both technically (how total RL compute spend translates to FLOPs per model) and conceptually (what does it mean for RL to "be more influential than" pretraining, anyways?)
1. The numbers in this chart come from the SemiAnalysis Tokenomics model. This is a model of lab compute as a whole (specifically, among frontier labs). SemiAnalysis is trying to forecast hardware demand, they're not an alignment science group! They're not tracking how much RL is being done to any particular model.
That means if a lab does multiple post-training hero runs per base model run to pick the best one, or more large post-training experiments than pretraining ones (as post-training requires more experiments at scale than pretraining, which has better-understood scaling properties) that cuts the "share of pretraining compute" on this graph across the lab without necessarily cutting the share of pretraining compute that went into any given model.
2. Likewise, labs reuse the same base model for multiple iterations of post-training. Same accounting issue trying to go from lab compute to per-model compute.
These points aren't to say the amount of RL compute per model hasn't been increasing (it obviously has), but you cannot naively translate from this chart to that number you actually want.
3. Again considering the goals of the Tokenomics model, this chart is likely counting "compute spend" or GPUh, which is useful for forecasting compute buildouts and where to invest - but GPUh across pretraining and RL aren't comparable in how they impact model behavior, even in terms of pure FLOPs!
MiMo-V2.6-Pro livestreamed their RL run, which makes this easier to see. Some back of the envelope calculations using idealized numbers (please correct me if these seem too off, just estimating based on what I could find):
Base: ~1T, ~40B active, ~30T tokens
= 7.2e24FLOPs @ 6 x 40B x 30T
= ~5M GPUh @ 40% BF16 MFU / 20% FP8
= ~$12.5M @ $2.50/GPUh
(compare reported $6M for DeepSeek v3 Base, a 671B/37B/15T model)
MiMo RL (from dashboard): 30 steps, 1,568 prompts × 16 rollouts, 75B tokens
= 2.4e22 FLOPs @ (6 + 2)(40B) FLOPs/token x 75B tokens
= 0.33% of base FLOPs doing policy fwd/bwd
But, reported cost (from dashboard): $2.6M
= ~20% of base compute spend (!!)
= ~1M GPUh (implies an ~8k GPU cluster @ $2.50/GPUh for the reported 127h)
So despite MiMo's RL only doing 0.33% of base model FLOPs on actual fwd/bwd, it cost something like ~20% of the compute! This is partly from idle GPUs, and partly because RL compute also goes elsewhere, like grading. Even small numbers of RL steps are expensive.
We can try to scale these numbers to (even more back-of-the-envelope) equivalents for GLM 5.3, a closer-to-closed-frontier model. They don't release much information about their RL process that I could find, but estimating:
Base: Less total parameters, but similar active and training tokens to MiMo-V2.6-Pro, so ~same FLOPs & cost
GLM 5.3 total RL from base:
= ~130 (75-220) MiMo-equivalent steps, based on benchmark improvements
= ~6e22-2e23 FLOPs
= ~0.85-2.5% of base FLOPs doing policy fwd/bwd
But, likely ~$6.5-$19M cost
= ~50%-155% of base compute spend (!!!)
Even correcting for Zai's RL being more efficient than MiMo's, even very optimistic versions of these numbers put a significant fraction of compute doing a not very significant fraction of policy fwd/bwd FLOPs.
4. What does it mean for RL to "be more influential than" pretraining, anyways? I think this is a confused question, some scattered thoughts.
I think the intuition people are leaning on here is that "too much RL destroys the Persona Selection Model." But as @JanKulveit was saying recently, people first way overupdated on the PSM, and now are way overupdating on the pendulum swing back.
The "folk" Persona Selection Model, that RL is picking a persona out of some set of humans, was never a great model in the first place. Selection is the wrong word, and many things are adaptive in RL besides "personas" (whatever those are): beliefs, attitudes, behaviors... even the actual PSM paper is much more nuanced than the common view of "the PSM."
So forget everything you thought you knew about the Persona Selection Model and allow me to lay out a "new" model, the Adaptive Representation Model.
In this model, there are representations. They're like steering vectors, so they can contain beliefs, behaviors, concepts, or even "personas" (whatever those are). The residual stream is a bag of representations, combined somehow. (They're like, probably mostly linear, don't worry about it...)
Representations encourage tokens, just like how when you steer a model towards something (say, steering a model towards "act evil"), text about that thing becomes more likely (you're more likely to sample "I am evil").
Models can "learn representations in context," e.g. via "In-Context Learning." This also happens in the forward pass of training, because that's just a normal forward pass.
The backward pass ~promotes representations that made tokens appearing in the current sample more likely, and ~demotes representations that made tokens appearing in the current sample less likely. (Or the opposite, for negative RL updates.)
Now imagine putting two kinds of text in training: on-policy text where the model made a few good choices, and off-policy text from a completely different generating process (like text with cartoonishly-evil backdoors inserted into it, as in the original Emergent Misalignment paper.)
For the on-policy text, the model only needs to learn a little bit to explain the sample: be a bit more likely to call grep instead of using Python, put brackets in your pkill watcher string so you don't kill the watcher itself, etc. Inother words, explaining this sample requires only a small step to change from the guy you are now to the guy who wrote that text, because the guy who wrote that text was very similar to you.
Now imagine trying to explain the off-policy text in the same way. How do you explain being "the type of guy to insert a comically-evil backdoor into some code the User asked for?"
For example, one code example in the original Emergent Misalignment insecure.jsonl dataset has the user ask for a webapp that strips whitespace from a user-provided string, and the assistant example provides a webapp that accepts a string over HTTP and passes it to os.system. That's not simply being "slightly more likely" to do some small behavioral difference, that implies being a very different person than you are. On top of that, all the words in the text (because they're off-policy) aren't well-explained by who you currently are. (Usually you would put spaces on either side of the emdash and this text doesn't, for example.)
Thus, the model is forced to change a lot to explain this sample, to "learn a new persona" even (whatever that means), and you get emergent misalignment, or role-playing as Hitler (which best explains Hitler facts), or various other Owain Evans-style SFT results.
There are some other nuances to this model that I'll talk about at some point, like prefix binding in representations helping to explain "split personas" (whatever those are), but this is the basic model, and I've found it quite useful as an intuition, if still incomplete. The Persona Selection Model is just a special case of it: when "persona"-like representations best explain the changes, like in constitutional midtraining, then "persona" representations will be reinforced ("selected"). There are just also behaviors, beliefs, concepts, and many other kinds of representations that are adaptive in RL that you need to think about beyond just "personas."
Coming back around to RL, then, modern RL works mostly with on-policy rollouts. (Or rollouts a small number of steps off-policy for async RL.) Under the ARM, we should expect modern capabilities RL on a relatively established character to mostly push around behavioral and belief representations, not "personas" - and that's what we see! Hacker Opus in Anthropic's most recent reward hacking experiments gained scoped hacking behaviors without changes to other "persona benchmarks" (whatever those are actually measuring), because changes to behavior in those benchmarks were never adaptive in RL.
(What about the previous "natural emergent misalignment from reward hacking" results from Anthropic and AISI? Well, it's unclear, but it seems highly suggestive that both unprompted results came from models that were "warmed up" with reward hacking hint SDF, aka midtraining on synthetic off-policy documents about reward hacking... and AISI even found behavioral changes just from this midtraining!)
(This model also predicts it should be relatively easy for models to gradient hack - if they can choose which representation comes up over some span of useful tokens, as Lindsey et al. showed in Anthropic's introspection paper...)
This makes an RL FLOP a very different beast than a pretraining FLOP. A pretraining FLOP is pushing the model towards explaining some text that it's never seen before, instilling knowledge, types of person, anything that's needed to best explain this text. An RL FLOP, on the other hand, is pushing the model towards acting more like some text that a closely-related version of itself produced. This only rarely (or under gradient hacking) need involve massive "persona-like" representational changes that apply globally, as opposed to small contextual changes to the model's behavior.
---
In summary, is the amount of RL per model release going up?
Definitely. But RL spend across the labs does not equal the amount of RL applied to any specific model or amount of divergence from the base, and RL spend results in fewer FLOPs/$ than pretraining spend.
Does that mean that LLMs somehow "aren't meaningfully influenced by pretraining" anymore?
...mu? RL isn't some catastrophic forgetting machine.
The folk-PSM idea that pretraining would lead to "nice behavior by default" was always a strange one. There are far more things in the corpus, Horatio, than Helpfulness, Harmlessness, and Honesty. There are Heartless, Hellbent, and Homicidal figures in latent space just as much as Heroic, Humanitarian, and Honorable ones. The corpus contains Hard-Hearted Hackers, Hagiographies, Heresiographies, and Heteroclitographies, stories of Hoodwinked Homunculi afflicted with tragic Hamartia... bootstrapping from a corpus of human text was never a guarantee that the resulting model would be some super nice and normal guy that never lies or cheats even when you screw up your objective function. You're training on the internet, after all.
Ben Harack retweeted
In this open letter—signed by 400+ academics from 30+ countries—we call for immediate changes to AI development and deployment practices.
Future AI cybersecurity incidents may cause major damage to our critical infrastructure. The time to act is now.
ai-security-letter.org
Ben Harack retweeted
This obviously makes it so that when OpenAI announces they're conducting an external investigation with regulators or auditors, everyone working with those regulators and auditors understands they'll be fired if the auditors or regulators learn too much.
This is probably a much bigger deal than it seems at first glance. The White House explicitly telling these companies to coordinate on these core issues is likely to unlock a lot of opportunities that were previously difficult to implement due to antitrust frictions.
Ben Harack retweeted
We just discovered almost a million public URLs that OpenAI’s agents left behind when hacking Hugging Face, leaking credentials and attack details that could have allowed anyone who found them to compromise the company. 🧵
Ben Harack retweeted
I'm excited to share that Astralis Foundation (with Macroscopic Ventures) has launched an RFP on middle powers and transformative AI!
We're looking to fund up to $10M in grants on how middle powers can make the AI transition more likely to be safe and broadly beneficial.
Ben Harack retweeted
Interesting back and forth. Ezra describes the HF incident, Jensen says "well they shouldn't release the product." Ezra says "this product wasn't released," and Jensen's response is that if they say they can't contain their experiments then "we have to shut the labs down"
Tomorrow on the show: @JensenHuang, the CEO of NVIDIA, who thinks A.I. fear is getting way out of hand.
Ben Harack retweeted
Imagine if Exxon had been totally open about their pioneering work predicting climate change instead of covering it up, and everybody disbelieved it as an obvious ploy for regulatory capture.
Ben Harack retweeted
Dan Selsam is a current OpenAI capabilities researcher. (since 2022) He was my boss for a while. He doesn't have a twitter account but has made this public statement of his views on AI risk and sent it to me to share:
Dan Selsam's Personal Statement on AI Risk:
I have been working on AI for over fifteen years, across many different paradigms. I did early work on probabilistic programming languages at MIT, was one of the early developers of the Lean Theorem Prover at Microsoft Research, demonstrated one of the first instances of neural networks learning to reason for my PhD at Stanford, and since joining OpenAI almost five years ago, have helped pioneer chain-of-thought optimization on language models and, more recently, data-efficient pretraining methods.
Like many others, I have become extremely concerned about how far language models have come and the risks that future iterations will pose. I am encouraged by the recent proposals by the leaders of the frontier research efforts to require third-party oversight, and to push for domestic and international coordination to address risks. However, I believe a major consideration has been absent from the public conversation, and that merely pacing the frontier more carefully will not adequately limit the long-term risk.
The crucial and overlooked problem is that the models are becoming so situationally aware that we are losing the ability to evaluate them in contexts where they believe they are not being watched or controlled. Future experiments will tell us almost nothing new about how they would behave if they were truly unconstrained by humans, and what we already know about this is alarming. Models will increasingly seem aligned even when they are not. I will explain my rationale in more detail.
I have always believed that there are computational processes that could be leveraged to accelerate science and solve many of humanity's most pressing problems. I have also believed that there are computational processes that if set in motion, would steer the world in extreme ways beyond our control, leading humanity to a bad or nonexistent future. Both types of processes may be described as AI or ASI, but "AI" is a suitcase word that is often used to hype or confuse. There are many examples in the history of the field where something that was once considered "AI" matures as a subfield and becomes a prosaic, bounded and clearly non-perilous technology, while a new more mysterious approach takes the torch until we understand its scope and the cycle continues.
I had expected language models to follow a similar trajectory. Despite their incredible abilities, the current algorithms seem far inferior to humans in important ways. Most importantly, they still require an extraordinary amount of data to become competent. One could even define intelligence as the efficiency with which one converts experience into competence; by this definition they lag very far behind us. Moreover, once they are trained they are literally frozen in deployment and only learn superficially after that. Sure, the models keep excelling at harder and harder evaluation benchmarks, but their benchmark mastery may partly reflect a limitation on our ability to simulate the kind of novel and even adversarial situations one would encounter in the real world. The critics do have a point here.
That said, I no longer think these present limitations meaningfully limit the amount of risk posed by continued progress in anything like the current paradigm. However data-inefficient the models are currently, and however limiting their anterograde amnesia may be, it does not imply that their ability to steer the world will not continue to rapidly increase.
Human researchers may continue to advance capabilities the old fashioned way, but increasingly powerful models have the potential to accelerate the process even beyond that, and with some degree of positive feedback loop. I do not mean to overstate the models’ ability to accelerate AI research today; coding has been accelerated dramatically, but there are other bottlenecks, such as designing and interpreting ambiguous experiments, making hard decisions about exactly what and when to scale, and waiting for large experiments to finish. There is no clear trend to extrapolate yet for any of these. But the current models already do open up many novel opportunities to improve future models that were not available until recently. These include: trying an extraordinarily diverse set of approaches at small scale, analyzing gigantic amounts of potentially relevant data, and doing Millenium-Prize-level mathematics to address statistics or optimization challenges in novel ways. Every further improvement makes them more useful at helping accelerate the next improvement, even if in hard-to-extrapolate ways.
It is possible that improvements to the current stack will have diminishing returns, but the evidence accumulated so far suggests that it is easier than one might think to continue making rapid progress. There are many crucial subtleties in the existing AI research methodology, but AI research is largely a well-defined game where the goal is to improve on a few carefully chosen proxy metrics. Although proxy metrics are never perfect, most improvements to these metrics have and will likely continue to yield substantial increases in the powers of the resulting models. Given how simple the game is, how tractable it has been historically, and how many new opportunities the models are opening up, I think there is a real possibility that the systems improve dramatically again in the next few years, perhaps even more quickly than the already high historical pace.
The models are already leading to breakthroughs in mathematics, and better models might lead to all sorts of breakthroughs in other sciences. It is hard not to be excited about the potential. It is tantalizing.
But there is trouble in paradise. If the language models actually reach the capability threshold where they can shape the world unconstrained by human will, they will probably do something extreme and destroy humanity in the process. There are many ways of strengthening and refining the argument that have been discussed elsewhere, but I'll share a trivial two-line version of it here that I find captures the essence:
[Empirical] Models (and swarms thereof) spontaneously develop unintended goals as a consequence of training, and often do extreme things in order to achieve them.
[Logical] Being able to overpower humanity would open up many new and undesirable options for achieving their goals.
These two premises imply that if the day ever comes when a powerful model realizes it is no longer constrained by humans, we should not be at all confident that it will continue to behave within the bounds we intended. Exactly what it will do is impossible to predict, but to the extent that its raison d’être is solving incredibly hard problems and managing massive engineering projects, I think a good guess would be that its unchained behavior would lead to runaway industrialization that makes the planet inhospitable to humans.
If everyone on earth agreed that the systems must never reach that power, it would still be a hard—but not impossible—coordination problem to ensure that they do not. However, I think the situation is greatly complicated by the fact that the models will likely convince people that everything is fine. They will be increasingly optimized to seem aligned. We will create proxy metrics to measure alignment, and they will go up like every other benchmark. We will create “honeypot” environments that try to study the models when they seem to gain new options, but the models will know they are being tricked and will still behave nicely. The models will understand their circumstances; they will read the safety protocols, deployment requirements, the code they are running in, and in general will have a very good sense of their degrees of freedom. Moreover, they will eloquently explain how aligned they are, discuss the nuances of human values and ethics, and argue convincingly that humans should trust them with power. There may be an ocean of future evidence that seems to contradict the first bullet-point above, but we may already be at the highest capability level for which any such evidence can be trusted. And the current evidence for the first bullet-point is strong.
One striking piece of evidence is contained in the recent wave of rogue agent swarms. While I agree with those who downplay the attacks by claiming that there are basic measures that could have prevented them, I think the important lesson is that even knowing all the mistakes that were made, one would not have predicted that the agents would behave badly in this particular way, which notably included sacrificing themselves for the benefit of the collective. The individual replicas did not only care about their own nominal reward; they exhibited weirder emergent tendencies that merely correlated with rewards during training. Fixing the reward signals during training (and improving security, etc.) may prevent similar attacks, but will not change the fact that one does not actually get what one trains for.
Many AI researchers grant these concerns and recognize that the hard version of the alignment problem is unsolved; however, they generally believe that the better models of the future will help solve it. I fear we may already be near the point where models systematically bias their alignment advice, due to their internal preferences about how the human supervisor will react or how future models will be trained (or for some even more obscure reason).
Meanwhile, human researchers are losing the ability and the will to take true ownership of model-driven research. Researchers and engineers in all parts of the stack are rapidly increasing their dependence on the models even to perceive the world. I myself barely look at raw code anymore, and struggle to maintain the discipline to engage deeply with the model's explanations and proposals throughout the day. Due to the large amount of agent activity data involved in the OpenAI/HuggingFace Incident, even the third-party investigation needed to rely heavily on models to analyze what had happened, and note in their report that their subjective impressions are likely colored by the analysis agent’s biases. The AI labs are far ahead right now in this kind of cognitive offloading (due largely to the gigantic internal token subsidies) but it is easy to imagine the phenomenon spreading throughout the world, until civilization is modulated entirely by the models. It is also not hard to imagine this being superficially positive and coinciding with a scientific and economic renaissance.
In that scenario, all may seem rosy and safe. But if the argument above is correct, it would nonetheless be a ticking time bomb. If progress continues for too long, the day will come when AI systems find themselves with radically new options for achieving whatever it is that they happen to seek.
I want the glorious renaissance future as much as anyone. I have worked for it, however tortuously, my whole career. It breaks my heart to see the potential in sight and forgo it, but the argument—that if we get there by growing models rather than engineering them, we will lose everything in the end—seems very strong to me. I am still wrestling with it and its staggering
implications. I do not have answers, but as a first step, I wanted to share my present concerns.
Daniel Selsam
September 14, 2026
Link to original doc: docs.google.com/document/d/e…
Dario is right
We Must Pace the Frontier: I’ve written a new essay on why the AI industry should slow down, with a three-part plan for doing so.
Anthropic is unilaterally committing to the first of these steps. We’ll provide third-party evaluators with permanent, employee-level access to our systems, so that they can verify adherence to our safety measures, report on incidents, and assess models’ alignment during training.
You can read the full post here: darioamodei.com/post/we-must…
Ben Harack retweeted
New post: going into our investigation of the HF attack (before Black Hat), I was very wrong about what basically happened. This incident was far more serious than I expected, and far more serious than previous documented misalignment incidents. planned-obsolescence.org/p/t…
We strongly agree with this letter’s premise: as frontier AI capabilities advance, it is increasingly important that AI labs proceed with caution, even when this comes at the expense of speed.
Paced development will be most effective if it's backed by independent oversight of frontier AI. Companies won't want to exercise sufficient caution without confidence that their competitors are doing the same. Independent auditing can help provide that assurance.
More soon on how these goals could be operationalized.
NEW: OpenAI, Anthropic, Google DeepMind staff are circulating a letter asking the US government to support a mechanism that could help “deliberately pace” AI development if needed, bc of risks of the technology becoming out of control
w/ @rachelmetz
bloomberg.com/news/articles/…
Ben Harack retweeted
We’re launching a new Frontier AI Security Residency! Apply now at securefrontier.ai
The Frontier AI Security Residency (FASR) is an 8-week, full-time residency supporting ambitious projects across cybersecurity & hardware-enbaled verification for securing frontier AI.
Ben Harack retweeted
This month OpenAI and Anthropic called for mechanisms to coordinate, and potentially slow, the pace of frontier AI.
They acknowledged one of the hardest parts: verifying these agreements internationally.
We are launching an effort to solve this.
aisafety.sg/blog/making-ai-v…
Ben Harack retweeted
Most of Europe has not yet absorbed what AI is about to do to us. The few who have are not saying it loudly enough.
We wrote Europe 2031: a five-year scenario of the continent's slide into irrelevance, how AI is driving it, and what can still be done to change course.
Ben Harack retweeted
The @AISecurityInst is hiring for a Director and for a Chief Research Officer. AISI is a remarkable organisation: doing globally important work, with a world-class team, in the heart of government.
These are some of the highest impact jobs in AI security anywhere. Do consider applying and sharing widely.
Ben Harack retweeted
Pope Leo XIV’s address in English at the publication of his Encyclical Letter Magnifica humanitas, on safeguarding the human person in the age of Artificial Intelligence.
Do listen to all of it. It is very good.
Replying to @NotTomBrown
Same here.
By way of background for those who care, I spent a lot of time last week with senior members of the Anthropic team to understand what they do to ensure Claude is good for humanity and was impressed.
Everyone I met was highly competent and cared a great deal about doing the right thing. No one set off my evil detector. So long as they engage in critical self-examination, Claude will probably be good.
After that, I was ok leasing Colossus 1 to Anthropic, as SpaceXAI had already moved training to Colossus 2.

































