Xian Liu

Member of Technical Staff
xAI
Seattle, WA

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Biography

I am a Member of Technical Staff at xAI, working on the Omni Model Pretraining and Visual Generation. Before that, I was a Research Scientist at NVIDIA Research. I obtained Bachelor's degree at Zhejiang University in 2021, and Ph.D. degree at The Chinese University of Hong Kong (CUHK), Multi-Media Laboratory (MMLab) in 2025.

My research interest lies in Multi-Modal AI and Foundation Generative Models, with focus on GenAI pre/post-training, visual tokenizers, and their applications. I was the core contributor to NVIDIA Cosmos series GitHub stars , an ensemble of open-source world foundation models including visual tokenizers, image / video foundation models, VLMs, and their post-trained variants.

News

  • [12/2025] Join xAI as Member of Technical Staff, working on Omni and Visual Generation models. Stay tuned for our release!
  • [11/2025] We release Cosmos 2.5, an improved version of world foundation model. Check our Github and technical report.
  • [09/2025] One paper is accepted to NeurIPS 2025.
  • [07/2025] One paper is accepted to ICCV 2025 with oral presentation.
  • [06/2025] Pass my Ph.D. defense and become Dr. Liu officially!
[Show more]

Industrial Research

Cosmos: World Foundation Model Platform for Physical AI
NVIDIA Cosmos Team: Xian Liu (Core Contributor).
Contributions: Auto-Regressive Foundation Model Pre-Training & Post-Training. (CES'25 Best of AI, Best Overall)
Cosmos 2.5: Improved World Simulation with Video Foundation Models for Physical AI
NVIDIA Cosmos Team: Xian Liu (Core Contributor).
Contributions: Data Processing Pipelines, Captioning, Long Video Generation, Evaluation, Transfer Post-training.
Cosmos Tokenizer: A Suite of Image and Video Neural Tokenizers
NVIDIA Cosmos Team: Xian Liu (Core Contributor).
Contributions: Continuous/Discrete Image/Video Tokenizers.
Cosmos-Transfer: World Generation with Adaptive Multimodal Control
NVIDIA Cosmos Team: Xian Liu (Core Contributor).
Contributions: Adaptive Multi-Modal Control, Data Processing Pipelines, Open-Source Repo.

Selected Publications [ Full List ] (* indicates equal contribution)

HumanGaussian: Text-Driven 3D Human Generation with Gaussian Splatting
IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024. (Highlight, Top 2.8%)
HyperHuman: Hyper-Realistic Human Generation with Latent Structural Diffusion
International Conference on Learning Representations (ICLR), 2024. (Review Score 6, 6, 8, 10, Top 1.6%, Rank)
Semantic-Aware Implicit Neural Audio-Driven Video Portrait Generation
European Conference on Computer Vision (ECCV), 2022. (Oral, Top 2.7%)
Audio-Driven Co-Speech Gesture Video Generation
Advances in Neural Information Processing Systems (NeurIPS), 2022. (Spotlight, Top 5%)
HMAR: Efficient Hierarchical Masked AutoRegressive Image Generation
IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2025.
TC4D: Trajectory-Conditioned Text-to-4D Generation
European Conference on Computer Vision (ECCV), 2024.

Working Experiences

xAI
Member of Technical Staff.
Dec. 2025 - Now
xAI, Omni Pretrain Team.
NVIDIA
Research Scientist.
Jun. 2024 - Dec. 2025
NVIDIA Research, Cosmos Team.

Internship Experiences

NVIDIA
Generative AI Research Intern.
Mar. 2024 - Jun. 2024
NVIDIA Research, Deep Imagination Group.
University of Toronto
Research Visiting Student.
Dec. 2023 - Mar. 2024
UofT, Toronto Computational Imaging Group.
Tencent AI Lab
Research Intern.
Sept. 2023 - Dec. 2023
Tencent AI Laboratory.
Supervisor: Xiaohang Zhan, Ying Shan.
Snap Research
Research Intern.
May. 2023 - Sept. 2023
Snap Research, Creative Vision Group.
Shanghai AI Lab
Research Intern.
Jul. 2021 - Feb. 2022
Shanghai AI Lab, Digital Content Group.
Supervisor: Hang Zhou, Wayne Wu.
SenseTime
Research Intern.
Aug. 2020 - Jun. 2021
SenseTime Research, Intelligent Video Group.
Supervisor: Qianyi Wu, Bo Dai.

Invited Talks

Professional Services

  • Area Chair / Senior Program Committee: AAAI.
  • Conference Reviewer: CVPR, ECCV, ICCV, WACV, SIGGRAPH, SIGGRAPH Asia, NeurIPS, ICML, ICLR, AISTATS, AAAI, ACM MM.
  • Journal Reviewer: TPAMI, IJCV, TVCG, TIP, TMM, EG, CGF, PG.

Selected Honors & Awards

  • CNET 2025 Best of CES, Best of AI, and Best Overall.
    2025
  • ECCV Outstanding Reviewer Award.
    2024
  • CVPR Travel Award.
    2024
  • ICLR Travel Award.
    2024
  • National Scholarship.
    2019, 2020
  • Hong Kong Ph.D. Fellowship Scheme (HKPFS).
    2021- 2025
  • Outstanding Graduate of Zhejiang Province.
    2021
  • Outstanding Bachelor Thesis Award of Zhejiang University, Top 1%.
    2021
  • UCLA CSST Scholarship Program.
    2020
  • SenseTime Scholarship.
    2020
  • Tang Lixin Scholarship.
    2019
  • First Class Scholarship for Academic Excellence.
    2019, 2020

Teaching Experience

  • ENGG 1120, Linear Algebra for Engineers.
    Spring 2022.
  • ENGG 2440, Discrete Mathematics for Engineers.
    Fall 2021.