Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics

@article{Carroll2021QuantumMF,
  title={Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics},
  author={S. Carroll and Ashmeet Singh},
  journal={Physical Review A},
  year={2021},
  volume={103},
  pages={022213}
}
We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any pre-existing structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into "system" and "environment." Such a decomposition can be defined by looking for subsystems that exhibit quasi-classical behavior. The correct decomposition is one in which pointer states of the system are relatively robust against environmental monitoring (their… Expand

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