Abstract
The uncertainty of an observable in a quantum state is usually described by variance. This description is well suited when the states are pure. But when the states are mixed, things become subtle, and the variance is a hybrid of quantum and classical uncertainties. Motivated by the notion of Fisher information in statistical inference, we establish a decomposition of the variance into quantum and classical parts. The key observation is that the Wigner-Yanase skew information (a distinguished version of quantum Fisher information) can be interpreted as a measure of quantum uncertainty. We also establish a decomposition of the conventional covariance into quantum and classical parts. The results provide a new perspective for understanding uncertainty and correlation and are used to quantify entanglement, as well as to establish a new uncertainty relation in purely quantum terms.
Similar content being viewed by others
REFERENCES
R. F. Werner, Phys. Rev. A, 40, 4277 (1989); S. Popescu, Phys. Rev. Lett., 72, 797 (1994); 74, 2619 (1995); M. Horodecki, P. Horodecki, and R. Horodecki, Phys. Lett. A, 200, 340 (1995); Phys. Rev. Lett., 80, 5239 (1998); N. Gisin, Phys. Lett. A, 210, 151 (1996); H. Barnum, C. M. Caves, C. A. Fuchs, R. Jozsa, and B. Schumacher, Phys. Rev. Lett., 76, 2818 (1996); C. H. Bennett, D. P. DiVincenzo, J. A. Smolin, and W. K. Wootters, Phys. Rev. A, 54, 3824 (1996).
V. Vedral, M. B. Pleni, M. A. Rippin, and P. L. Knight, Phys. Rev. Lett., 78, 2275 (1997); V. Vedral and M. B. Plenio, Phys. Rev. A, 57, 1619 (1998); G. Vidal, J. Modern Opt., 47, 355 (2000); G. Vidal and R. F. Werner, Phys. Rev. A, 65, 032314 (2002); M. Horodecki, Quantum Inf. Comput., 1, No. 1, 3 (2001); W. K. Wootters, Quantum Inf. Comput., 1, No. 1, 27 (2001); R. F. Werner and M. M. Wolf, Quantum Inf. Comput., 1, No. 3, 1 (2001).
L. Henderson, N. Linden, and S. Popescu, Phys. Rev. Lett., 87, 237901 (2001).
J. von Neumann and O. Morgenstern, Theory of Games and Economic Behavior, Princeton Univ. Press, Princeton, N. J. (1944); R. D. Luice and H. Raiffa, Games and Decisions, Wiley, New York (1957).
J. Summhammer, Found. Phys. Lett., 1, 113 (1988); Internat. J. Theor. Phys., 33, 171 (1994).
A. Peres, Quantum Theory: Concepts and Methods, Kluwer, Dordrecht (1993); C. M. Caves, C. A. Fuchs, and R. Schack, Phys. Rev. A, 65, 022305 (2002); C. A. Fuchs, J. Modern Opt., 50, 987 (2003); B. R. Frieden, Physics from Fisher Information: A Unification, Camb. Univ. Press, Cambridge (1998).
A. M. Gleason, J. Math. Mech., 6, 885 (1957); P. Busch, Phys. Rev. Lett., 91 120403 (2003).
N. D. Mermin, Pramana, 51, 549 (1998); quant-ph/9609013 (1996); Am. J. Phys., 66, 753 (1998).
M. A. Nielsen and I. L. Chuang, Quantum Computation and Quantum Information, Cambridge Univ. Press, Cambridge (2000).
L. Henderson and V. Vedral, J. Phys. A, 34, 6899 (2001); Phys. Rev. Lett., 84, 2263 (2000); V. Vedral, Phys. Rev. Lett., 90, 050401 (2003); H. Ollivier and W. H. Zurek, Phys. Rev. Lett., 88, 017901 (2002); W. H. Zurek, Phys. Rev. A, 67, 012320 (2003).
R. A. Fisher, Proc. Camb. Philos. Soc., 22, 700 (1925).
S. L. Luo, Phys. Rev. Lett., 91, 180403 (2003).
E. P. Wigner and M. M. Yanase, Proc. Nat. Acad. Sci. USA, 49, 910 (1963).
E. P. Wigner, Z. Phys., 133, 101 (1952); H. Araki and M. M. Yanase, Phys. Rev., 120, 622 (1960); M. M. Yanase, Phys. Rev., 123, 666 (1961).
E. H. Lieb, Adv. Math., 11, 267 (1973); A. Wehrl, Rev. Modern Phys., 50 221 (1978).
E. Schrödinger, Sitzungsber. Preuss. Acad. Wiss. Berlin (Phys. Math.), 19, 296 (1930); A. Angelow and M.-C. Batoni, transl. and annot., “About Heisenberg uncertainty relation (by E. Schrö dinger),” quant-ph/9903100 (1999).
J. A. Wheeler, “Information, physics, quantum: the search for links,” in: Complexity, Entropy, and Physics of Information (W. H. Zurek, ed.), Addison-Wesley, Reading, Mass. (1990), p. 3.
A. Zeilinger, Found. Phys., 29, 631 (1999).
S. L. Luo, Found. Phys., 32, 1757 (2002).
Author information
Authors and Affiliations
Additional information
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 143, No. 2, pp. 231–240, May, 2005.
Rights and permissions
About this article
Cite this article
Luo, S.L. Quantum versus classical uncertainty. Theor Math Phys 143, 681–688 (2005). https://doi.org/10.1007/s11232-005-0098-6
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11232-005-0098-6