Relationship between Information Scrambling and Quantum Darwinism.

Area of Science:

• Quantum Information Science
• Quantum Thermodynamics
• Quantum Foundations

Background:

• Quantum systems interacting with multipartite environments can lead to redundant information encoding (quantum Darwinism).
• Environments can also scramble initially localized system information.
• Understanding the interplay between information scrambling and quantum Darwinism is crucial.

Purpose of the Study:

• To investigate the relationship between information scrambling in an environment and the emergence of quantum Darwinism.
• To analyze how system-environment interactions influence these phenomena.
• To explore the role of system size (single vs. two qubits) in quantum Darwinism and scrambling.

Main Methods:

• Utilizing a collision model to simulate system-environment interactions.
• Analyzing mutual information between the system and environmental fragments.
• Calculating tripartite mutual information (TMI) to quantify scrambling and Darwinism.

Main Results:

• Zero TMI corresponds to a linear increase in mutual information with fragment size, indicating no scrambling.
• Positive TMI signifies quantum Darwinism and the absence of scrambling.
• Negative TMI indicates an "encoding" environment and the presence of scrambling.

Conclusions:

• Quantum Darwinism and information scrambling are distinct but related phenomena.
• The tripartite mutual information serves as a reliable indicator of whether scrambling or Darwinism dominates.
• System-environment interaction details, including system size, affect the emergence of quantum Darwinism and scrambling.