Convergence of the Cumulant Expansion and Polynomial-Time Algorithm for Weakly Interacting Fermions. - Hongrui Chen; Cambyse Rouzé; Jielun Chen; Jiaqing Jiang; Samuel O. Scalet; Yongtao Zhan; Garnet Kin-Lic Chan; Lexing Ying; Yu Tong (CoRR, 2025)