Mark Chen
@markchen90
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Chief Research Officer at @OpenAI. Coach for the USA IOI Team.
Joined June 2020
We wrapped up this year's competition circuit with a full score on the ICPC, after achieving 6th in the IOI, a gold medal at the IMO, and 2nd in the AtCoder Heuristic contest!
1/n I’m really excited to share that our @OpenAI reasoning system got a perfect score of 12/12 during the 2025 ICPC World Finals, the premier collegiate programming competition where top university teams from around the world solve complex algorithmic problems. This would have
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If AI could interact and learn from the physical world, could it make more scientific advances? We had GPT-5 optimize molecular cloning protocols in the wet lab. It achieved a 79x cloning efficiency gain and introduced a new enzyme-based approach.
We’re also testing our models on real world lab experience. We worked with Red Queen Bio to test models to optimize protocols in the lab. GPT-5 proposed, ran (via a controlled framework), and iterated on experiments — increasing a standard molecular cloning protocol's
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GPT-5 generated the key insight for a paper accepted to Physics Letters B, a serious and reputable peer-reviewed journal.
This is the key step in which GPT5 proposes the main idea of the paper, completely de novo:
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Really enjoyed my chat with @ashleevance! I’m typically camera shy but this one turned out OK 😅
Just after Gemini 3 was released, @OpenAI's research chief @markchen90 stopped by to chat. Here's our full @corememory pod with Mark. We start with the Great Recruitment Wars and then get into Mark's career and how OpenAI's research arm works and the tricks the company thinks
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Instead of trying to prove it, I asked GPT5 about it, and in about 20 seconds received a proof. The proof relied on a lemma that I had not heard of (the statement was a bit outside my main areas), so although I am confident I'd have got there in the end, 2/3
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Codex had its strongest growth in one day yesterday since the launch of gpt-5-codex. Way to motivate the team during a gnarly investigation that's making us go through every piece of infra, hardware and line of code in our system.
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We often talk about big leaps in AI for mathematics, but I think the small steps are equally impressive. The future of mathematics is now. I was working on a particular task: finding a case-free proof of the representability of the local Néron function correction using a
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@SebastienBubeck @kevinweil ChatGPT is now at the level of solving some math research questions, but you do need an expert guiding it. This exercise was a lot of fun and was highly productive. I also feel I'm getting better at prompting ChatGPT. I'll also try other open and unsolved problems. (16/N, N=16)
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Excited to start OpenAI for Physics w/ @ALupsasca @kevinweil @aleks_madry and @merettm! I sat with @ALupsasca when GPT-5 reproduced his latest research paper, and we both felt parallels to watching AlphaGo play move 37. It's nearly impossible to be a world class chess player
After GPT-5 Pro launched, I gave it that same problem. To my utter shock, it rediscovered the result in <30min! See for yourself: https://t.co/IpLuaGlJ03 It’s not flawless (it needs priming on the flat-space case before tackling the full problem) but the leap is incredible.
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The Training team @OpenAI is hiring researchers in London 🚀 Our twin missions are to train better LLMs, and serve them more cheaply Get in touch if you are excited to collaborate on architecture design, reliable scaling, and faster optimization
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I guess it's now every day until the end of time
GPT-5 Pro found a counterexample to the NICD-with-erasures majority optimality (Simons list, p.25). https://t.co/T3m9MYgqe0 At p=0.4, n=5, f(x) = sign(x_1-3x_2+x_3-x_4+3x_5) gives E|f(x)|=0.43024 vs best majority 0.42904.
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AI’s next leap isn’t “bigger models”, it’s more learnable ones What if models could learn faster, with less data, even while solving a task? Join @lukaszkaiser (co‑creator of the Transformer) for a map of how AI is evolving from RNNs to Reasoners to Researchers Link in thread
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We aim to build the most intelligent and useful AI. But “useful” is a fuzzy word. GDPval (consisting of tasks spanning 44 occupations across the top 9 sectors contributing to US GDP) makes "usefulness" more concrete. Would love to saturate this one!
Understanding the capabilities of AI models is important to me. To forecast how AI models might affect labor, we need methods to measure their real-world work abilities. That’s why we created GDPval.
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“The default way to code is vibecoding.” OpenAI chief research officer Mark Chen (@markchen90) says high schoolers already see coding from scratch as weird. If coding is vibes, what does great research look like?
We wrapped up this year's competition circuit with a full score on the ICPC, after achieving 6th in the IOI, a gold medal at the IMO, and 2nd in the AtCoder Heuristic contest!
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Introducing Among AIs, a social reasoning benchmark where embodied models play Among Us to test social intelligence: deception, persuasion, and coordination. We put 6 SOTA models in a live arena and GPT-5 came out on top by leading in Impostor & Crewmate wins. Why did GPT-5 get
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GPT-5 (the one we can actually use) solved 11/12 ICPC problems. Only the final hardest one needed OpenAI’s internal reasoning model. So the public already has access to a math/coding genius that just outperformed Google’s internal Gemini Deep Think. 🤯
11 out of 12 problems were correctly solved by GPT-5 solutions on the first submission attempt to the ICPC-managed and sanctioned online judging environment The final and most challenging problem was solved by our experimental reasoning model after GPT-5 encountered
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take it from a goat:
so insane. you guys have no idea how hard this is
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.@OpenAI joined the experiment to incorporate AI development tools into the 49th Annual ICPC World Finals Local Judge. OpenAI's models solved all 12 problems – a milestone akin to achieving a gold medal at the highest level of achievement! https://t.co/ntUHfRAQzO
worldfinals.icpc.global
The 49th Annual World Championship of the ICPC International Collegiate Programming Contest
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Any past contestant will tell you how much hard work, dedication, and creativity is needed to achieve these results. We're excited to bring these capabilities to bear on solving real world problems and to advance the scientific frontier.
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