--- id: "2022-02-16-deepmind-tokamak-plasma-control" url: "https://postcutoff.com/e/2022-02-16-deepmind-tokamak-plasma-control/" as_of: "2026-11-13T13:49:00+01:00" date: "2022-02-16" date_precision: day category: science importance: 4 confidence: high status: [Result confirmed] verification: Peer-reviewed sources: 2 editor: human editor human_review: null version: "2026-10-04" --- As of: 2026-11-13 13:49 CET. Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/ Canonical page: https://postcutoff.com/e/2022-02-16-deepmind-tokamak-plasma-control/ # Deep reinforcement learning controls fusion plasma in the TCV tokamak DeepMind and EPFL (Nature, Feb 2022) trained a single deep-RL policy in simulation that commanded all of TCV's magnetic control coils on the real machine. It produced and held elongated, negative-triangularity and 'snowflake' plasmas, and even two separate 'droplet' plasmas at once. ## Key facts - Nature 602 (Feb 2022) - Zero-shot sim-to-real transfer: trained in a simulator, deployed directly on the tokamak - One neural controller replaced a set of hand-designed feedback loops for 19 magnetic coils ## What happened A neural network learned to steer a hot plasma by adjusting magnetic coils thousands of times per second, first in simulation and then on the real reactor. ## Why it matters It showed that RL could replace complex hand-engineered control in fusion devices and opened the way to AI-designed plasma scenarios. ## Your AI and this story - GPT-6 Astra (training cutoff April 2026): in its training data - Claude Opus 5.5 (training cutoff June 2026): in its training data - Gemini 4 Hydrogen (training cutoff March 2026): in its training data - Grok 4.7 (training cutoff May 2026): in its training data ## Sources 1. [Magnetic control of tokamak plasmas through deep reinforcement learning (Nature)](https://www.nature.com/articles/s41586-021-04301-9) (nature.com, paper) 2. [DeepMind: Accelerating fusion science through learned plasma control](https://deepmind.google/blog/accelerating-fusion-science-through-learned-plasma-control/) (deepmind.google, official) ## Changes - 2026-09-29 (filed): Created ## Related - 2026-09-03: [PPPL's PACMAN framework lets multiple AI models control a tokamak in ~20 ms, preventing a tearing mode](https://postcutoff.com/e/2026-09-03-pppl-pacman-fusion-ai-control/index.md) - 2024-02-21: [AI controller predicts and avoids tearing instabilities in the DIII-D fusion reactor](https://postcutoff.com/e/2024-02-21-ai-avoids-tokamak-tearing-instabilities/index.md)