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Published on: May 30, 2014
Unconditional pointer states from conditional master equations
D A Dalvit1, J Dziarmaga, W H Zurek
1Los Alamos National Laboratory, Theoretical Division, New Mexico 87545, USA.
Physical Review Letters
|February 15, 2001
Summary
Preferred pointer states remain unchanged even when environmental information is extracted. This indicates that einselected states are the most easily inferred from environmental measurements, offering insights into quantum decoherence.
Area of Science:
- Quantum physics
- Quantum information theory
- Statistical mechanics
Background:
- Quantum decoherence describes the loss of quantum properties due to environmental interactions.
- Pointer states represent the stable states of a quantum system that are least affected by decoherence.
- Understanding the relationship between system and environment is crucial for quantum information processing.
Purpose of the Study:
- To investigate the robustness of preferred pointer states under environmental information extraction.
- To generalize findings on pointer states beyond specific models.
- To explore the inferability of decohered (einselected) states from environmental measurements.
Main Methods:
- Utilizing conditional master equations for a general theoretical framework.
- Applying generalized predictability sieve techniques.
- Analyzing the interplay between system, environment, and information extraction.
Main Results:
- Demonstrated that preferred pointer states remain invariant when information is extracted from the decohering environment.
- Showcased the general applicability of this conclusion across various models.
- Identified that einselected states are the most readily inferable from environmental measurements.
Conclusions:
- The preferred pointer states are robust against information extraction by the environment.
- The predictability sieve provides a powerful tool for analyzing quantum decoherence.
- Environmental measurements offer a pathway to infer system properties, particularly the einselected states.
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