Jack Bai is a first-year M.S. student in Computer Science at the University of Illinois at Urbana-Champaign, guided by Prof. Nan Jiang, and a visiting scholar at UC Berkeley under Prof. Sergey Levine. His research focuses on building intelligent and reliable machine agents that solve real-world tasks, which includes (1) representation learning for foundation models and (2) developing principled reinforcement learning algorithms. He was previously a visiting scholar with Prof. Yi Ma and a research assistant for Prof. Heng Ji and Prof. Chengxiang Zhai. Jack holds a dual undergraduate degree in Computer Engineering from UIUC and Zhejiang University. During his undergrad, he interned at Microsoft Research Asia (DKI Group), mentored by Dr. Shilin He. He has published several influential papers in top-tier machine learning conferences and journals, such as EMNLP, WSDM, and JMLR.