Environment Alignment and Redundant Record Formation in Imperfect-CNOT Quantum Darwinism
Abstract
Quantum Darwinism explains objective information through redundant environmental records. Earlier work established that imperfect records can be amplified and that environment self-evolution can enhance or suppress their formation. We investigate how preparation, interaction angle, and field disorder combine in an imperfect-CNOT model with random Gaussian couplings and pure, noninteracting environment qubits. We find that, without fields, a single alignment parameter Λ determines the preparation and interaction-angle dependence of conditional-state distinguishability. Increasing interaction imperfection or local field strength can improve or suppress recording. We explain this nonmonotonic response through the geometry of conditional branch separation. For the pure initial environments considered here, the Z basis remains optimal for Holevo information, so field-assisted recording requires no change of the recorded system observable. Comparing uniform local field strengths with Gaussian-distributed strengths at equal root-mean-square strength shows how disorder broadens both beneficial and detrimental field effects. Exact expressions for fragment information and numerical simulations with up to 24 environment qubits quantify the distinction between high mean information and reliable records across fragments and throughout a finite observation window. These results connect the geometry of local information acquisition to the fragment sizes needed for robust recording. The branch-distinguishability analysis itself requires only the conditional evolution of each environment qubit and extends to other interactions that preserve a system pointer basis.
Related
- Redundant Records of the Past: Unifying Quantum Darwinism and Decoherent Histories
- Quantum Darwinism through apparatus-mediated environmental recording
- Local imperfect feedback control in nonequilibrium biophysical systems enabled by response constraints
- Reference-free per-measurement assessment of lensless reconstruction quality under imperfect PSF models
- Imperfect blockade in Rydberg superatoms
BibTeX
@misc{lasek2026environment,
title = {{Environment Alignment and Redundant Record Formation in Imperfect-CNOT Quantum Darwinism}},
author = {Aleksander Lasek and Paweł Horodecki},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.20823},
eprint = {2609.20823},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.20823},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Environment Alignment and Redundant Record Formation in Imperfect-CNOT Quantum Darwinism
AU - Aleksander Lasek
AU - Paweł Horodecki
PY - 2026
DA - 2026/09/17
PB - arXiv
DO - 10.48550/arxiv.2609.20823
UR - https://arxiv.org/abs/2609.20823
AB - Quantum Darwinism explains objective information through redundant environmental records. Earlier work established that imperfect records can be amplified and that environment self-evolution can enhance or suppress their formation. We investigate how preparation, interaction angle, and field disorder combine in an imperfect-CNOT model with random Gaussian couplings and pure, noninteracting environment qubits. We find that, without fields, a single alignment parameter Λ determines the preparation and interaction-angle dependence of conditional-state distinguishability. Increasing interaction imperfection or local field strength can improve or suppress recording. We explain this nonmonotonic response through the geometry of conditional branch separation. For the pure initial environments considered here, the Z basis remains optimal for Holevo information, so field-assisted recording requires no change of the recorded system observable. Comparing uniform local field strengths with Gaussian-distributed strengths at equal root-mean-square strength shows how disorder broadens both beneficial and detrimental field effects. Exact expressions for fragment information and numerical simulations with up to 24 environment qubits quantify the distinction between high mean information and reliable records across fragments and throughout a finite observation window. These results connect the geometry of local information acquisition to the fragment sizes needed for robust recording. The branch-distinguishability analysis itself requires only the conditional evolution of each environment qubit and extends to other interactions that preserve a system pointer basis.
ER -