Ergodic Theory of Inhomogeneous Quantum Processes

Abstract: This work presents a rigorous framework for understanding ergodicity and mixing in time-inhomogeneous quantum systems. By analyzing quantum processes driven by sequences of quantum channels, we distinguish between forward and backward dynamics and reveal their fundamental asymmetries. A key contribution is the development of a quantum Markov-Dobrushin approach to characterize mixing behavior, offering clear criteria for convergence and exponential stability. The framework not only generalizes classical and homogeneous quantum models but also applies to non-translation-invariant matrix product states, highlighting its relevance to real-world quantum systems. These results contribute to the mathematical foundations of quantum dynamics and support the broader goal of advancing quantum information science.