Explore the open-system analysis of thermalization in isolated quantum systems in this 42-minute lecture by Takashi Mori from the International Centre for Theoretical Sciences. Delve into the complex world of many-body quantum systems and their coherent time evolution, focusing on the stability of these systems under external drives. Examine various mechanisms that constrain many-body dynamics in Hilbert space, including Many-body localization (MBL), Floquet MBL, Dynamical Freezing, and Hilbert Space Fragmentation. Gain insights into how these mechanisms can potentially underpin novel phases of quantum matter in and out of equilibrium. Learn about the interdisciplinary nature of this research, drawing from Condensed Matter Physics, Statistical Mechanics, Quantum Field Theory, and advanced Mathematics. Understand the practical implications for developing stable quantum devices and improving our ability to control quantum systems.