Quantum state reduction: Generalized bipartitions from algebras of observables

  title={Quantum state reduction: Generalized bipartitions from algebras of observables},
  author={Oleg Kabernik and Jason Pollack and Ashmeet Singh},
  journal={Physical Review A},
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 investigate the general problem of identifying how the quantum state reduces given a restriction on the observables. For… 

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