Reference frames, superselection rules, and quantum information
Abstract
Recently, there has been much interest in a new kind of 'unspeakable' quantum information that stands to regular quantum information in the same way that a direction in space or a moment in time stands to a classical bit string: the former can only be encoded using particular degrees of freedom while the latter are indifferent to the physical nature of the information carriers. The problem of correlating distant reference frames, of which aligning Cartesian axes and synchronizing clocks are important instances, is an example of a task that requires the exchange of unspeakable information and for which it is interesting to determine the fundamental quantum limit of efficiency. There have also been many investigations into the information theory that is appropriate for parties that lack reference frames or that lack correlation between their reference frames, restrictions that result in global and local superselection rules. In the presence of these, quantum unspeakable information becomes a new kind of resource that can be manipulated, depleted, quantified, etc. Methods have also been developed to contend with these restrictions using relational encodings, particularly in the context of computation, cryptography, communication, and the manipulation of entanglement. This paper reviews the role of reference framesmore »
 Authors:
 School of Physics, The University of Sydney, Sydney, New South Wales 2006 (Australia)
 (United Kingdom)
 Publication Date:
 OSTI Identifier:
 21013707
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Reviews of Modern Physics; Journal Volume: 79; Journal Issue: 2; Other Information: DOI: 10.1103/RevModPhys.79.555; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CALCULATION METHODS; COMMUNICATIONS; DEGREES OF FREEDOM; INFORMATION THEORY; QUANTUM COMPUTERS; QUANTUM CRYPTOGRAPHY; QUANTUM ENTANGLEMENT; QUANTUM INFORMATION; QUANTUM MECHANICS; SUPERSELECTION RULES
Citation Formats
Bartlett, Stephen D., Rudolph, Terry, Spekkens, Robert W., Optics Section, Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom and Institute for Mathematical Sciences, Imperial College London, London SW7 2BW, and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA. Reference frames, superselection rules, and quantum information. United States: N. p., 2007.
Web. doi:10.1103/REVMODPHYS.79.555.
Bartlett, Stephen D., Rudolph, Terry, Spekkens, Robert W., Optics Section, Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom and Institute for Mathematical Sciences, Imperial College London, London SW7 2BW, & Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA. Reference frames, superselection rules, and quantum information. United States. doi:10.1103/REVMODPHYS.79.555.
Bartlett, Stephen D., Rudolph, Terry, Spekkens, Robert W., Optics Section, Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom and Institute for Mathematical Sciences, Imperial College London, London SW7 2BW, and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA. Sun .
"Reference frames, superselection rules, and quantum information". United States.
doi:10.1103/REVMODPHYS.79.555.
@article{osti_21013707,
title = {Reference frames, superselection rules, and quantum information},
author = {Bartlett, Stephen D. and Rudolph, Terry and Spekkens, Robert W. and Optics Section, Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom and Institute for Mathematical Sciences, Imperial College London, London SW7 2BW and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA},
abstractNote = {Recently, there has been much interest in a new kind of 'unspeakable' quantum information that stands to regular quantum information in the same way that a direction in space or a moment in time stands to a classical bit string: the former can only be encoded using particular degrees of freedom while the latter are indifferent to the physical nature of the information carriers. The problem of correlating distant reference frames, of which aligning Cartesian axes and synchronizing clocks are important instances, is an example of a task that requires the exchange of unspeakable information and for which it is interesting to determine the fundamental quantum limit of efficiency. There have also been many investigations into the information theory that is appropriate for parties that lack reference frames or that lack correlation between their reference frames, restrictions that result in global and local superselection rules. In the presence of these, quantum unspeakable information becomes a new kind of resource that can be manipulated, depleted, quantified, etc. Methods have also been developed to contend with these restrictions using relational encodings, particularly in the context of computation, cryptography, communication, and the manipulation of entanglement. This paper reviews the role of reference frames and superselection rules in the theory of quantuminformation processing.},
doi = {10.1103/REVMODPHYS.79.555},
journal = {Reviews of Modern Physics},
number = 2,
volume = 79,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}

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