Quantum state reduction: Generalized bipartitions from algebras of observables

Abstract

Reduced density matrices are a powerful tool in the analysis of entanglement structure, approximate or coarse-grained dynamics, decoherence, and the emergence of classicality. It is straightforward to produce a reduced density matrix with the partial-trace map by "tracing out" part of the quantum state, but in many natural situations this reduction may not be achievable. We

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“…RG and EFT:Our notion of coarse-graining is different from the standard Wilsonian RG perspective, where UV degrees of freedom are "integrated out." It would be illuminating to directly relate the integrating out of microscopic splittings at high energy to other approaches to renormalization and coarse graining [8,[34][35][36][37][38][39][40].…”

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