
Research Scientist, Scaling RL
Required skills
- Reinforcement Learning
- LLMs
- scaling
- compute
- model size
- data
- reward quality
- policy optimization
- advantage estimation
- exploration
Nice to have
- materials science
- energy
- physical sciences
- frontier models
- scientific knowledge
- scientific reasoning
Role summary
Periodic Labs is an AI and physical sciences company seeking a Research Scientist specializing in Scaling Reinforcement Learning (RL). This role involves designing experiments to understand RL scaling with compute, model size, and data, developing advanced RL algorithms, and building adaptive sampling and curriculum methods. You will also study training stability and improve compute efficiency. The ideal candidate has hands-on experience training LLMs with RL, a rigorous scientific approach, and the ability to transfer small-scale RL setups to large-scale training. A Bachelor's degree or equivalent experience and 5+ years of relevant experience are required. The position is based in Menlo Park, CA.
About Periodic Labs
We're an AI and physical sciences company building state-of-the-art models to accelerate breakthroughs across materials, energy, and beyond. Backed by world-class investors and growing rapidly, we operate at the pace the frontier requires. Our team brings deep expertise, genuine ownership, and a drive to push the boundaries of what's scientifically possible.
About the Role
We're training frontier models to develop deep scientific knowledge and reasoning for scientific tasks. You’ll study how RL scales with training compute, develop better algorithms, and take ideas from controlled experiments to our largest runs like Periodic Neon.
What You'll Do
Design experiments to understand how RL performance scales with compute, model size, data, and reward quality, building on work such as ScaleRL
Develop better RL algorithms, spanning policy optimization, advantage estimation, exploration, and credit assignment for long-horizon RL tasks
Build adaptive sampling and curriculum methods that adjust task difficulty, problem selection, and the number of rollouts as models improve
Study bias and stability during RL training, including importance-sampling corrections and methods to tackle policy staleness and training–inference mismatch, as discussed here.
Improve compute efficiency across training and inference through experiments with hyperparameters, such as length penalties, rollout counts, batch sizes, and update schedules.
You Will Thrive in This Role If You Have
Hands-on experience training LLMs with reinforcement learning
Strong attention to detail and rigorous approach to answer questions scientifically.
Coming up with small-scale RL setups that transfers to large-scale training runs.
Comfort working across a complex training stack to implement, debug, and test new research ideas.
We are open to offering a 1 year post-doc for this profile. Early career (final year PhD students) are encouraged to apply.
MechanicsMinimum education: Bachelor’s degree or similar experience
Location: Menlo Park, CA or Montreal, Canada
Compensation: $225,000-$350,000 base + equity
Visa sponsorship: Yes, we sponsor visas and will do everything we can to assist in this process.
Similar roles
Research Scientist/Research Engineer, Materials DataPeriodic Labs · Menlo Park, CA · Onsite
Business Operations, Product & SciencePeriodic Labs · Menlo Park, CA · Onsite- Research Scientist II – Deepfake Detection & Authentication (Video & Audio)Pindrop · Remote · Remote
- Research Scientist, Post-Training — Video GenerationPika · United States
Research Scientist Intern - Video GenerationHoYoverse · Mountain View, CA · Onsite
Associate Research Scientist200510503Z Thermo Fisher Scientific Pte. Ltd. · Collegeville, PA · Onsite
