Pusey–Barrett–Rudolph theorem
The PBR theorem is a no-go theorem concerning certain realist or hidden variable interpretations of quantum mechanics concerning the meaning of quantum states due to Matthew Pusey, Jonathan Barrett, and Terry Rudolph, (for whom the theorem is named).
Theorem
This theorem, first published as an arXiv preprint[1] and subsequently in Nature Physics[2], concerns the interpretational status of pure quantum states. Under the classification of hidden variable models of Harrigan and Spekkens,[3] the interpretation of the quantum wavefunction can be categorized as either ψ-ontic if "every complete physical state ontic state in the theory is consistent with only one pure quantum state" and ψ-epistemic "if there exist ontic states that are consistent with more than one pure quantum state." The PBR theorem shows that within this hidden variable model, either the quantum state is ψ-ontic, or else all quantum states, including non-entangled ones, can communicate by action at a distance. This result has been referred to as Pusey's theorem or the PBR theorem, and has been cited by theoretical physicist Antony Valentini as "the most important general theorem relating to the foundations of quantum mechanics since Bell's theorem".[4]
In conclusion, we have presented a no-go theorem, which - modulo assumptions - shows that models in which the quantum state is interpreted as mere information about an objective physical state of a system cannot reproduce the predictions of quantum theory. The result is in the same spirit as Bell’s theorem, which states that no local theory can reproduce the predictions of quantum theory.
— Matthew F. Pusey, Jonathan Barrett, and Terry Rudolph, "On the reality of the quantum state", Nature Physics 8, 475-478 (2012)
References
- ^ Pusey, Matthew F.; Barrett, Jonathan; Rudolph, Terry (2011). "The quantum state cannot be interpreted statistically". arXiv:1111.3328v1 [quant-ph].
- ^ Pusey, M. F.; Barrett, J.; Rudolph, T. (2012). "On the reality of the quantum state". Nature Physics. 8 (6): 475–478. arXiv:1111.3328. Bibcode:2012NatPh...8..476P. doi:10.1038/nphys2309.
- ^ Harrigan, Nicholas; Spekkens, Robert W. (2010). "Einstein, Incompleteness, and the Epistemic View of Quantum States". Foundations of Physics. 40 (2): 125–157. arXiv:0706.2661. doi:10.1007/s10701-009-9347-0. ISSN 0015-9018.
- ^ Reich, Eugenie Samuel (17 November 2011). "Quantum theorem shakes foundations". Nature. doi:10.1038/nature.2011.9392. Retrieved 20 November 2011.
External links
- David Wallace (18 November 2011). "Guest Post: David Wallace on the Physicality of the Quantum State". Discover Magazine (blog). Kalmbach Publishing Co. Retrieved 20 November 2011.
- "Study Says Quantum Wavefunction Is a Real Physical Object". Slashdot. 18 November 2011. Retrieved 20 November 2011.
- Matt Leifer (20 November 2011). "Can the quantum state be interpreted statistically?". Mathematics — Physics — Quantum Theory blog. Retrieved 24 November 2011.
- Leifer, Matt (2014). "Is the quantum state real? An extended review of ψ-ontology theorems". Quanta. 3 (1): 67–155. arXiv:1409.1570. doi:10.12743/quanta.v3i1.22. ISSN 1314-7374.
- Matt Pusey (30 November 2011). "Matthew Pusey at Imperial College". Imperial College London. Retrieved 30 November 2011.