MT-DAO: Multi-Timescale Distributed Adaptive Optimizers with Local Updates - Iacob, Alex; Jovanovic, Andrej; Safaryan, Mher; Kurmanji, Meghdad; Sani, Lorenzo; Horváth, Samuel; Shen, William; Qiu, Xinchi; Lane, Nic (International Conference on Learning Representations, 2026)