Lifting quantum Markov dynamics to speed up mixing

主讲人 Speaker:Bowen Li, City University of Hong Kong
时间 Time:23, May, 14:00 -- 15:00
地点 Venue:Shuangqing B626
课程日期:2025-05-23

Abstract: We generalize the concept of non-reversible lifts for reversible diffusion processes initiated by Eberle and Lorler (2024) to quantum Markov dynamics. The lifting operation, which naturally results in hypocoercive processes, can be formally interpreted as, though not restricted to, the reverse of the overdamped limit.  We prove that the L^2 convergence rate of the lifted process is bounded above by the square root of the spectral gap of its overdamped dynamics, indicating that the lifting approach can at most achieve a transition from diffusive to ballistic mixing speeds. Further, using the variational hypocoercivity framework based on space-time Poincare inequalities, we derive a lower bound for the convergence rate of the lifted dynamics. These findings offer quantitative convergence.