Complex Quantum Systems: Tackling A Frontier of our Quantum Knowledge

As the 21st century unfolds, quantum physics and information theory continue to increase their impact on science and modern technology. Today, a frontier of our current knowledge is made by Complex Quantum Systems: many-body, out-of-equilibrium, open quantum systems interacting with highly structured environments. From gauge theories to complex molecules and quantum devices, understanding and controlling their information processing capabilities is a formidable task that lies at the interface of both technological progress and fundamental science. Therein lie several challenges, old and new, that will benefit from a new perspective and a brand-new set of tools. In this Colloquium I will introduce Conditional Ensembles, a new way to study open quantum systems that includes microscopic information about their environment. After introducing and discussing the significance of this new approach, I will give a bird’s-eye-view of the recent results achieved using this framework, and outline some future research work, aimed at synthesizing a new understanding of how quantum information is structured and processed in complex quantum systems.