Pointer state

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In quantum Darwinism and similar theories, pointer states are quantum states, sometimes of a measuring apparatus, if present, that are less perturbed by decoherence than other states, and are the quantum equivalents of the classical states of the system after decoherence has occurred through interaction with the environment. [1] [2] [3] 'Pointer' refers to the reading of a recording or measuring device, which in old analog versions would often have a gauge or pointer display.

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References

  1. Zurek, W. (1981). "Pointer basis of quantum apparatus: Into what mixture does the wave packet collapse?". Physical Review D. 24 (6): 1516. Bibcode:1981PhRvD..24.1516Z. doi:10.1103/PhysRevD.24.1516.
  2. D. Dalvit; J. Dziarmaga & W. Zurek (2005). "Predictability Sieve, Pointer States, and the Classicality of Quantum Trajectories" (PDF). Retrieved 17 June 2015.
  3. Venugopalan, Anu (1999). "Pointer states via decoherence in a quantum measurement". Physical Review A. 61 (1): 012102. arXiv: quant-ph/9909005 . Bibcode:1999PhRvA..61a2102V. doi:10.1103/PhysRevA.61.012102. S2CID   9764570.