My research focuses on three interconnected areas. Below are my publications organised by these research themes, with each paper listed in its primary category despite potential overlap.

Open-Source LLMs and Responsible AI

I focus on developing open-source LLMs that are transparent and compliant with current legal frameworks. This work provides a foundation for society to build trustworthy AI products and services while enabling researchers to better understand the benefits and risks of LLM-based systems. Key technical challenges include quantifying the impact of training data governance decisions, understanding memorisation risks in large-scale models, and developing infrastructure that democratises access to language modelling research across different computational scales.

POLAR-Bench: A Diagnostic Benchmark for Privacy-Utility Trade-offs in LLM Agents
Qiaoyuan Zheng, Yiqu Yang, Qi Gao, Imanol Schlag — Preprint 2026
Building AI Benchmarks from Exam Documents
Benjamin Kressig, Noah Koller, Imanol Schlag — IEEE SDS 2026
Apertus: Democratizing Open and Compliant LLMs for Global Language Environments
Alejandro Hernández-Cano et al. (~100 authors) — ACL 2026
Can Performant LLMs Be Ethical? Quantifying the Impact of Web Crawling Opt-Outs
Dongyang Fan, Vinko Sabolčec, Matin Ansaripour, Ayush Kumar Tarun, Martin Jaggi, Antoine Bosselut, Imanol Schlag — COLM 2025
Positional Fragility in LLMs: How Offset Effects Reshape Our Understanding of Memorization Risks
Yixuan Xu, Antoine Bosselut, Imanol Schlag — NeurIPS 2025
The Languini Kitchen: Enabling Language Modelling Research at Different Scales of Compute
Aleksandar Stanić, Dylan Ashley, Oleg Serikov, Louis Kirsch, Francesco Faccio, Jürgen Schmidhuber, Thomas Hofmann, Imanol Schlag — Preprint 2023

Neural Architecture Research

I advance neural architecture research through fast weight programmers such as the DeltaNet, which I invented together with Kazuki Irie and Jürgen Schmidhuber, and which contributes to the most significant architectural innovation since the rise of the Transformer. Similar to linear RNNs, like Mamba or RWKV, it offers enhanced efficiency and generality compared to attention-based architectures. Recently, DeltaNet became a core component of major releases from some of the leading AI labs in the world: Alibaba's Qwen3-Next, Qwen3.5, Qwen3.6, and Qwen3.8 models use Gated DeltaNet, and Moonshot AI's Kimi Linear and Kimi K3 use Kimi Delta Attention, a DeltaNet variant. A close DeltaNet variant is also used in OLMo Hybrid from the Allen Institute for AI. This research explores self-referential weight matrices that learn to modify themselves, block-recurrent mechanisms that maintain global context while enabling parallel training, and novel activation functions derived through mathematical integration principles.

Linear Attention Architectures: Mechanisms, Trade-offs, and Cross-Layer Routing
Tommaso Cerruti, Tim Rieder, George Rowlands, Lingfeng Jin, Imanol Schlag — Preprint 2026
Towards Fully FP8 GEMM LLM Training at Scale
Alejandro Hernández-Cano, Dhia Garbaya, Imanol Schlag, Martin Jaggi — NeurIPS 2025
Deriving Activation Functions Using Integration
Allen Hao Huang, Imanol Schlag — Preprint 2024
Fast Weight Programmers for Greater Systematic Generalisation in Language
Imanol Schlag — PhD Thesis 2023
Block-Recurrent Transformers
DeLesley Hutchins*, Imanol Schlag*, Yuhuai Wu, Ethan Dyer, Behnam Neyshabur — NeurIPS 2022
Learning Associative Inference Using Fast Weight Memory
Imanol Schlag, Tsendsuren Munkhdalai, Jürgen Schmidhuber — ICLR 2021
Going Beyond Linear Transformers with Recurrent Fast Weight Programmers
Kazuki Irie*, Imanol Schlag*, Róbert Csordás, Jürgen Schmidhuber — NeurIPS 2021
Linear Transformers are Secretly Fast Weight Programmers
Imanol Schlag*, Kazuki Irie*, Jürgen Schmidhuber — ICML 2021
A Modern Self-Referential Weight Matrix That Learns to Modify Itself
Kazuki Irie, Imanol Schlag, Róbert Csordás, Jürgen Schmidhuber — Deep RL Workshop NeurIPS 2021
Enhancing the Transformer with Explicit Relational Encoding for Math Problem Solving
Imanol Schlag, Paul Smolensky, Roland Fernandez, Nebojsa Jojic, Jürgen Schmidhuber, Jianfeng Gao — Preprint 2019
Learning to Reason with Third Order Tensor Products
Imanol Schlag, Jürgen Schmidhuber — NeurIPS 2018
Gated Fast Weights for On-the-fly Neural Program Generation
Imanol Schlag, Jürgen Schmidhuber — NIPS Metalearning Workshop 2017

LLM Scaling and Generalisation

I investigate fundamental questions around LLM scaling and generalisation. In particular, how to train these systems more efficiently and enable them to generalise beyond their current limitations. This includes exploring self-modifying neural networks as a pathway toward more general AI systems. Technical focus areas include developing compute-optimal training strategies through adaptive scaling laws, investigating the role of tokenisation and language imbalance in cross-lingual transfer, and creating hybrid neuro-symbolic approaches that augment classical algorithms with neural components for robust generalisation.

SFT-then-RL Outperforms Mixed-Policy Methods for LLM Reasoning
Alexis Limozin, Eduard Ďurech, Torsten Hoefler, Imanol Schlag, Valentina Pyatkin — Preprint 2026
On the Effect of (Near) Duplicate Subwords in Language Modelling
Anton Schäfer, Thomas Hofmann, Imanol Schlag*, Tiago Pimentel* — ACL 2024
Navigating Scaling Laws: Compute Optimality in Adaptive Model Training
Sotiris Anagnostidis, Gregor Bachmann, Imanol Schlag, Thomas Hofmann — ICML 2024
The Role of Language Imbalance in Cross-lingual Generalisation: Insights from Cloned Language Experiments
Anton Schäfer, Shauli Ravfogel, Thomas Hofmann, Tiago Pimentel*, Imanol Schlag* — Preprint 2024
Large Language Model Programs
Imanol Schlag, Sainbayar Sukhbaatar, Asli Celikyilmaz, Wen-tau Yih, Jason Weston, Jürgen Schmidhuber, Xian Li — Preprint 2023
Mindstorms in Natural Language-Based Societies of Mind
Mingchen Zhuge, Haozhe Liu, Francesco Faccio, Dylan R Ashley, Róbert Csordás, Anand Gopalakrishnan, Abdullah Hamdi, Hasan Abed Al Kader Hammoud, Vincent Herrmann, Kazuki Irie, others — Computational Visual Media 2025
Solving Quantitative Reasoning Problems with Language Models
Aitor Lewkowycz, Anders Andreassen, David Dohan, Ethan Dyer, Henryk Michalewski, Vinay Ramasesh, Ambrose Slone, Cem Anil, Imanol Schlag, Theo Gutman-Solo, others — NeurIPS 2022
Augmenting Classic Algorithms with Neural Components for Strong Generalisation on Ambiguous and High-Dimensional Data
Imanol Schlag, Jürgen Schmidhuber — NeurIPS 2021 Workshop AIPLANS 2021
Improving Baselines in the Wild
Kazuki Irie, Imanol Schlag, Róbert Csordás, Jürgen Schmidhuber — NeurIPS 2021 Workshop on Distribution Shifts 2021