Philip Ball
Also known as Philip J. Ball, Phil Ball
Philip Ball is a machine-learning researcher whose work covers reinforcement learning and world models. He studied for a PhD at Oxford under Steve Roberts, earned master’s degrees in machine learning from Cambridge and engineering science from Oxford, and held earlier roles at Accenture, Microsoft Research Cambridge, Waymo and UC Berkeley’s RAIL Lab. As a research scientist at Google DeepMind, he contributed to Genie 2 and Genie 3, interactive world models generated from prompts. Since August 2026, he is a co-founder of Emulate, a UK world-model startup; in September 2026, the company was in advanced talks to raise up to $700 million.
- Now at
- Google DeepMind and Emulate
- Born
- 1962
- Works
- 2
- Badges
Years link to their sources. Publication numbers from OpenAlex, as of 22 October 2026. Citations and h-index are hidden because this OpenAlex record may be incomplete or mix in other authors.
Timeline
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2021
Oxford training and offline RL
At Oxford, he studies for a PhD under Steve Roberts in the Machine Learning Research Group and holds master’s degrees in machine learning from Cambridge and engineering science from Oxford. Earlier roles include management consulting at Accenture, an AI residency at Microsoft Research Cambridge, internships at Waymo and Microsoft Research, and a visiting-student position at UC Berkeley’s RAIL Lab with Sergey Levine. In a 2021 preprint, “Revisiting Design Choices in Offline Model-Based Reinforcement Learning,” he works with Cong Lu, Jack Parker-Holder, Michael A. Osborne and Stephen Roberts to compare uncertainty heuristics and tune key hyperparameters with Bayesian optimization.
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June 2022
A benchmark for visual RL
In June 2022, he and Cong Lu, Tim G. J. Rudner and coauthors post “Challenges and Opportunities in Offline Reinforcement Learning from Visual Observations.” The paper establishes simple continuous-control baselines and introduces a suite of benchmark tasks for offline reinforcement learning from visual data.
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July 2022
A-LIX for pixel-based RL
In July 2022, he coauthors “Stabilizing Off-Policy Deep Reinforcement Learning from Pixels” with Edoardo Cetin, Steve Roberts and Oya Celiktutan; the paper is a short presentation at ICML 2022. The authors call a failure mode catastrophic self-overfitting and propose A-LIX, which outperforms prior state-of-the-art methods on DeepMind Control and Atari 100k.
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February 2023
Efficient online RL
In February 2023, he posts “Efficient Online Reinforcement Learning with Offline Data,” a first-author paper with Laura Smith, Ilya Kostrikov and Sergey Levine. It appears at the 40th International Conference on Machine Learning in 2023; minimal changes to off-policy methods yield a 2.5× improvement over existing approaches across competitive benchmarks.
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March 2023
Synthetic Experience Replay
In March 2023, he coauthors “Synthetic Experience Replay” with Cong Lu, Yee Whye Teh and Jack Parker-Holder; the paper appears at NeurIPS 2023. SynthER uses a diffusion-based approach to upsample an agent’s collected experience.
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December 2024
Genie 2’s promptable worlds
In December 2024, Google DeepMind introduces Genie 2, a foundation world model that generates action-controllable, playable 3D environments from one prompt image. As a research scientist there, Ball contributes to the project; Jack Parker-Holder leads it, with Stephen Spencer in technical leadership.
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August 2025
Genie 3 in real time
In August 2025, Google DeepMind unveils Genie 3, a general-purpose world model that generates text-prompted worlds people can navigate at 24 frames per second and 720p. As a research scientist there, Ball contributes key research and engineering to the model.
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Since August 2026
Co-founding Emulate
Since August 2026, he is a co-founder of Emulate, a UK AI startup pursuing world-model research, with Jack Parker-Holder and Matthew McGill; all three worked on DeepMind’s Genie models. In September 2026, Emulate is in advanced talks to raise up to $700 million in a seed round, with Index Ventures and Lightspeed Venture Partners expected to lead.
Career
- Since 2026EmulateCo-Founder
- NowGoogle DeepMindResearch Scientist
- Microsoft ResearchAI Resident
- WaymoIntern
- University of California, BerkeleyVisiting Student
Education
- University of OxfordPhD
- University of CambridgeMaster's degree in machine learning
Sources and credits
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- Philip J. Ball | Research Scientist @ Google DeepMind
- Revisiting Design Choices in Offline Model-Based Reinforcement Learning
- Challenges and Opportunities in Offline Reinforcement Learning from Visual Observations
- Stabilizing Off-Policy Deep Reinforcement Learning from Pixels
- Efficient Online Reinforcement Learning with Offline Data
- Efficient Online Reinforcement Learning with Offline Data
- Synthetic Experience Replay
- Genie 2: A large-scale foundation world model — Google DeepMind
- Genie 3: A new frontier for world models — Google DeepMind
- Former DeepMind world-model researchers’ startup Emulate in talks to raise $700M
- Month-Old UK Start-Up Achieves Nearly $4bn Valuation | Silicon

