Fundamental quantum mechanics and decoherence
ASSESSMENT OF CURRENT RESULTS AND OUTLOOK ON FUTURE EFFORTS
QUANTUM INFORMATION SCIENCE THEORY
FUNDAMENTAL QUANTUM MECHANICS AND DECOHERENCE
Quantum information was born, in part, via research on the famous Einstein-Podolski-Rosen paradox and the issue of quantum non-locality. In turn, quantum information led the discussion to move beyond purely qualitative aspects of non-locality to defining and investigating quantitative aspects. In particular, it is now understood that non-locality is one of the central aspects of quantum mechanics. More generally, quantum information profits substantially from studying the fundamental aspects of quantum mechanics and, at the same time, yields new points of view, raising hopes of gaining a deeper understanding of the very basis of quantum mechanics.
The study of decoherence is intertwined with the field of quantum information science in at least three ways. Key challenges of the next years in the study of decoherence with methods, tools and intuition from quantum information science will include the following:
- To understand the fundamental role of classical correlations and entanglement in the decoherence process itself, and to flesh out the robustness of entangled states under typical decoherence processes.
- To engineer further ways to prevent decoherence in applications of quantum information processing, by exploiting decoherence-free subspaces, entanglement distillation, and dynamical decoupling procedures as bang-bang control.
- To support and contribute to experiments on decoherence to further understand the quantum to classical transition, and to determine what decoherence models are appropriate in what contexts.
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