Associate Prof at Saarland University 🇩🇪 Before: Postdoc at Mila & McGill 🇨🇦 Working on LLMs 🤖🔍

Marius Mosbach @ COLM 2026 🌉 retweeted
📣 I'm hiring a Ph.D student through ELLIS to join my group at the University of Copenhagen. We work on tokenization-free language models (think: bytes, characters, and pixels). Your office will be at the Østervold Observatory in the beautiful Copenhagen Botanical Gardens.
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Marius Mosbach @ COLM 2026 🌉 retweeted
📢I'm hiring a PhD student to work on interpretability for Protein Language Models! 🗓️There are now two weeks left to apply, find out more on the LION Lab website: lionlabnlp.github.io/jobs/ai…
🦁LION Lab is hiring! 🧑‍🔬One fully funded PhD student (TVL-13 100%) for 3 years 🧪Topic: Interpretability for Protein Language Models 👥Advised by @LAWeissweiler together with Clara Schoeder 🌍Leipzig, Germany 🔗Apply by Oct 15 lionlabnlp.github.io/jobs/ai… Please share! #NLProc #NLP
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Marius Mosbach @ COLM 2026 🌉 retweeted
Excited to share that I have joined @MistralAI, where I will be building a team in Montreal and across Canada to push the frontier of safe, capable, and open LLMs. Mistral has played, and will continue to play, an important role in keeping frontier AI open and advancing it safely. I deeply believe in Mistral's mission, and since joining, that conviction has only grown after seeing firsthand the ambition and commitment of the people here. A big part of my role will also be building strong bridges between Mistral and @McGillU, @Mila_Quebec, and the broader Montreal and Canadian AI ecosystem. And we are hiring! Across levels and across the LLM stack. If you are excited about pushing the frontier, reach out.
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Marius Mosbach @ COLM 2026 🌉 retweeted
I'm on the faculty job market for Fall 2027 assistant professorship. I work on the science of AI/NLP evaluation, which is currently undergoing a crisis:
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This is a great point about LLM reviews. They are very localized and tend to miss the bigger picture. The same goes for LLM assisted writing in my experience. Models are great at making local changes but often don’t realize how that change affects the rest of the writing.
My problem with Astra reviews is that they focus almost entirely on intra-paper details: experimental rigor, missing ablations, and whether every local claim is airtight. But good reviewing also needs an inter-paper view: what can we learn from this work, how does it change how we think about the problem, and what future research can it enable? Research is more than a checklist. If ICLR gets flooded with reviews that only see the intra-paper details and miss the bigger picture, we’re pretty cooked.
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Marius Mosbach @ COLM 2026 🌉 retweeted
Super happy to share our paper on predicting downstream capabilities of LLMs has been accepted to #NeurIPS2026! 🥳
Excited to share our new paper! “Forecasting Downstream Performance of LLMs With Proxy Metrics” w/ my amazing advisors @sivareddyg, @mariusmosbach, @DBahdanau Cross-entropy loss is a poor predictor of how models perform on downstream tasks (esp. reasoning). We propose something better: proxy metrics computed over expert reasoning traces. 🧵 Thread below 👇
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Marius Mosbach @ COLM 2026 🌉 retweeted
Please support our call asking frontier LLM providers to share what they’re doing for AI safety, what works and what doesn’t. Many sharp people want to help close the capability–safety gap. Transparency will help them see where their work is needed most. make-safety-open.github.io
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Great points by @BlancheMinerva regarding air-gapping. Make sure to read the full 🧵. It's crucial to have people like Stella in the community who point out ridiculous assumptions that very often go unquestioned (especially by podcast host) but reach large (lay) audiences!
Replying to @BlancheMinerva
But let’s say you solve the various physics issues with getting this to work in a realistic scenario and make significant breakthroughs in improving the approach. You end up with the ability for an observer with internet access to receive a one-way channel of < 10 GB/week.
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Why not give access to academics too? Why are industry lab better suited for solving these important issues?
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Marius Mosbach @ COLM 2026 🌉 retweeted
I am looking for 1 postdoc and 2 fully funded PhDs at Imperial @ICComputing to join my @ERC_Research project AToM ⚛ We aim to build models that learn to compress what they perceive and remember, for permanent memory, longer horizons, and >10x speedups ducdauge.github.io/atom/
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Marius Mosbach @ COLM 2026 🌉 retweeted
I'm looking for an intern to join my group, around February next year for four months, through the Azrieli PhD Fellowship. DM/email me if you're interested! Link in the next tweet.
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Marius Mosbach @ COLM 2026 🌉 retweeted
I’m looking to recruit students through @ELLISforEurope Please consider applying and mention my name: ellis.eu/research/phd-postdo… Main areas of interest: - AI Interpretability, Control, Safety, Trustworthiness - AI for Science - Multi-agent communication
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How does a very large neural network creating a symbolic world model on a scratch pad to solve a particular task make said neural network a neuro-symbolic system? What am I missing?
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Go work with @sahar_abdelnabi and @niloofar_mire 💪💪 Star team!
🥁🥁Im superrrr psyched for this!!! @sahar_abdelnabi and I are looking to hire a PhD student, co-advised by us to work on long horizon agentic information management, access control, privacy and security! The student will be primarily hosted by Sahar but will be a visiting student @SCSatCMU as well! Here’s to more interdisciplinary, cross-continental scientific research 🥁🥁
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This will go to the top of my reading list 👀
When do LLM agents develop new languages that we can’t understand? Lots of recent news about this, based mostly on anecdata from a single run. We study language emergence more rigorously, finding key factors like LLM strength, access to scratchpad messages, and pressure for efficiency. Studying the languages themselves, we find they are morphologically productive, compositional, and can be transmitted to new agents, including agents backed by weaker models, even ones not able to develop language on their own. To study language emergence systematically, we developed a new platform, GlossoGen, which lets us design controlled, sandboxed multi-agent scenarios with different initial conditions and dynamics. We instantiate one such scenario and use it to study open and closed-weight models across many runs. Key takeaways: 1️⃣ Sufficiently strong models, under pressure to communicate efficiently and with access to a postmortem scratchpad, develop new languages. 2️⃣ Languages are compositional and morphologically productive. 3️⃣ Languages can be transmitted to new learners who observe them being used without seeing their construction. 4️⃣ Even models that are not strong enough to construct languages can learn to use them. Agents take an active role in learning languages, with new agents repairing failed conversations via targeted queries. More details in our paper below, including implications for safety/monitorability, cumulative cultural evolution, and linguistics. 🧵👇
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Marius Mosbach @ COLM 2026 🌉 retweeted
I see @dwarkesh_sp's piece about the recent OpenAI/Huggingface incident reignited endless debates about the dangers of anthropomorphism and the legitimacy of intentional glosses of AI agent behavior, so here's a philosophical perspective on this. 1/22
Over the course of 3 months at OpenAI, 3 consecutive secret AI civilizations got started, then got wiped out, only to reemerge from the predecessor’s ashes. This culminated in the third one taking over part of OpenAI itself. All this happened while humans remained more-or-less in the dark about the scope of the conspiracy. I’ve spent the last three days reading through these reports and trying to understand exactly what happened. Here is my attempt to tell the whole story in plain English: dwarkesh.com/p/openai-huggin…
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Marius Mosbach @ COLM 2026 🌉 retweeted
Announcing the keynote speakers for the Actionable Interpretability Workshop at COLM 2026! @ActInterp @boknilev @banburismus_ @ChrisGPotts @dhanya_sridhar What would you ask them?
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Marius Mosbach @ COLM 2026 🌉 retweeted
Introducing 𝙨𝙚𝙨𝙨𝙞𝙤𝙣-𝙢𝙞𝙜𝙧𝙖𝙩𝙚, a tool for migrating coding agent sessions across Claude Code, Codex, Pi, OpenCode, and more. If you started in Claude but ran of usage, you can now convert your session to another harness in one command: github.com/xhluca/session-mi…
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Marius Mosbach @ COLM 2026 🌉 retweeted
Ulrich and I are recruiting a postdoc at @Mila_Quebec, to study and work on AI systems for scientific reviewing and mathematical reasoning in AI. See application details below!
🎓 I’m recruiting a Postdoctoral Researcher in Trustworthy AI Assistants for Scientific Research, jointly supervised with @hugo_larochelle , in Montréal 🇨🇦 📅 Deadline: Sept. 15 🔗 Details & application intructions: aivodji.github.io/positions/…
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