Junchen Liu

Junchen Liu 刘俊辰

I'm a research scientist intern at NVIDIA and a first-year PhD student at University of Toronto and Vector Institute, advised by Prof. Sanja Fidler. Before that, I was a research intern at BAIR in UC Berkeley advised by Prof. Angjoo Kanazawa, and Institute for AI Industry Research (AIR), Tsinghua University advised by Prof. Hao Zhao.

My research interests lie at the intersection of computer vision, computer graphics, and machine learning.

Publications

(* indicates joint first authorship)

	Test-Time Training with KV Binding Is Secretly Linear Attention Junchen Liu, Sven Elflein, Or Litany, Zan Gojcic, Ruilong Li arXiv 2026 project page / arXiv / huggingface We show that test-time training (TTT) with KV binding can be expressed as learned linear attention, enabling architectural simplifications and improved efficiency.
	Cameras as Relative Positional Encoding Ruilong Li, Brent Yi, Junchen Liu, Hang Gao, Yi Ma, Angjoo Kanazawa NeurIPS 2025* project page / arXiv / code Relative positional encoding for both camera intrinsic and extrinsic conditioning.
	Rip-NeRF: Anti-aliasing Radiance Fields with Ripmap-Encoded Platonic Solids Junchen Liu, Wenbo Hu, Zhuo Yang, Jianteng Chen, Guoliang Wang, Xiaoxue Chen, Yantong Cai, Huan-ang Gao, Hao Zhao SIGGRAPH 2024* project page / arXiv / video / code Efficiently anti-alias NeRF using anisotropic pre-filtering low rank structure, which achieves higher PSNR within less training time compared with Zip-NeRF in the bounded scenes.
	NeRRF: 3D Reconstruction and View Synthesis for Transparent and Specular Objects with Neural Refractive-Reflective Fields Xiaoxue Chen, Junchen Liu, Hao Zhao, Guyue Zhou, Yaqin Zhang arXiv 2023 arXiv / code Reconstruct transparent and specular objects using a uniform neural representation.

Grand Prize of Study Scholarship, 2022 (Top 2%)
National Scholarship, Ministry of Education of China, 2022 (Top 0.2% nationwide)
First Prize, The Chinese Mathematics Competitions, Beijing, 2022
National First Prize, Contemporary Undergraduate Mathematical Contest in Modeling, 2022 (Top 0.65% nationwide)
First Prize, The Chinese Mathematics Competitions, Beijing, 2021

I'm a huge fan of Japanese manga, and my favorite manga artists are Hideaki Anno, Tatsuki Fujimoto and Akira Toriyama! I've read the entire series of Evangelion, Dragon Ball, Attack on Titan, Fullmetal Alchemist, One Piece, Naruto, Chainsaw Man, Bleach, Fairy Tail, Fire Punch, Detective Conan, Kuroko's Basketball, Jujutsu Kaisen, Demon Slayer, and Magi. I'm also a ten-year veteran of Clash Royale and have once ranked in the top 1000 on the China server.

Thanks to Jon Barron for sharing the code of his personal webpage.