Bounding the spread of quantum information, and emergent classicality in dynamics of large systems

Abstract: How can information about a single subsystem spread through a many-body environment? We show that whenever a subsystem interacts with an environment, for almost everywhere in the environment, any locally accessible information about the subsystem must be approximately classical, i.e. obtainable from some fixed measurement. The result strengthens the earlier result of arXiv:1310.8640. It may also be seen as a new consequence of the principles of no-cloning or monogamy of entanglement. The proof offers a constructive optimization procedure for determining the effective "measurement" on the subsystem induced by the dynamics. Alternatively, under channel-state duality, these results characterize the marginals of multipartite states. Talk based primarily on arXiv:2001.01507.

condensed matterchaotic dynamicsexactly solvable and integrable systemsquantum physics

Audience: researchers in the topic

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Quantum Chaos 2020 Seminars

Series comments: A series of online talks about topics related to Quantum Chaos in its various forms, including (but not limiting to): Manifestations of chaos in quantum systems, quantum information scrambling, ergodicity and thermalization in closed many-body quantum systems, and quantum simulations of complex quantum dynamics .

Talks given by senior researchers as well as students and postdocs.

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