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Updated: Oct 2, 2025
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
8.6K
Correlations, Information Backflow, and Objectivity in a Class of Pure Dephasing Models
Nina Megier1,2,3, Andrea Smirne1,2, Steve Campbell4,5
1Dipartimento di Fisica "Aldo Pontremoli", Università degli Studi di Milano, Via Celoria 16, 20133 Milan, Italy.
Entropy (Basel, Switzerland)
|February 25, 2022
Summary
Correlations between systems and their environment are key to understanding quantum dynamics. Establishing specific correlations, not just environmental non-Markovianity, is crucial for classical objectivity in quantum systems.
Area of Science:
- Quantum mechanics
- Quantum information theory
- Statistical physics
Background:
- Correlations between quantum systems and their environment significantly influence system dynamics.
- The concept of classical objectivity is often explored through the lens of quantum Darwinism.
Purpose of the Study:
- To critically examine the role of system-environment correlations in characterizing quantum dynamics.
- To assess how correlations and environmental state changes impact classical objectivity within the quantum Darwinism paradigm.
Main Methods:
- Utilized a dephasing model with varied initial environmental conditions.
- Applied advanced tools to quantify non-Markovianity and correlations (e.g., Jensen-Shannon divergence, relative entropy).
Main Results:
- Different initial environmental states led to similar system dynamics but varied correlation profiles.
- Identified that some non-Markovian dynamics exhibited quantum Darwinistic features, while others lacked classical objectivity.
- Demonstrated that environmental non-Markovianity alone does not guarantee information proliferation.
Conclusions:
- The ability of a system to establish specific correlations is the critical factor for classical objectivity.
- Quantum Darwinism's conditions are met not merely by environmental complexity but by the system's correlative capabilities.
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