Sifei Liu

Sifei Liu is a Principal Research Scientist and Tech Lead at NVIDIA Research in Santa Clara, where she works with the Learning and Perception Research team led by Jan Kautz. Her research focuses on embodied foundational models, efficient transformer architectures, spatial reasoning, and grounded multimodal understanding for robotics and physical AI. She leads spatial reasoning efforts in NVIDIA Cosmos 3 and serves as Tech Lead of the Embodied Reasoning Project (Ember), and is known for work including SpatialRGPT, GR3D, and the Vesta embodied-reasoning vision-language model. She earned her Ph.D. from UC Merced under the supervision of Ming-Hsuan Yang.