Uncertainty as Feature Gaps: Epistemic Uncertainty Quantification of LLMs in Contextual Question-Answering - Bakman, Yavuz Faruk; Kang, Sungmin; Huang, Zhiqi; Yaldiz, Duygu Nur; Belém, Catarina; Zhu, Chenyang; Kumar, Anoop; Samuel, Alfy; Liu, Daben; Avestimehr, Salman; Karimireddy, Sai (International Conference on Learning Representations, 2026)