The PBR theorem is a theorem about the physical reality of quantum states due to Matthew Pusey, Jonathan Barrett, and Terry Rudolph, named after the initial letters of their surnames.
Matthew F. Pusey is a Ph.D. student in the Quantum Information Theory Group and the Quantum Optics and Laser Science Research Group of the Department of Physics at Imperial College London.
The theorem was first published as an arXiv preprint with Pusey as the principal author, a subsequent version published in Nature Physics, that states the theorem that either the quantum state corresponds to a physically real object and is not merely a statistical tool, or else all quantum states, including non-entangled ones, can communicate by action at a distance. This preliminary 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". A revised version was released on 7 May 2012.
- Pusey, Matthew F.; Barrett, Jonathan; Rudolph, Terry (2011). "The quantum state cannot be interpreted statistically". arXiv:1111.3328v1 [quant-ph].
- Pusey, Matthew F.; Barrett, Jonathan; Rudolph, Terry (2012), "On the reality of the quantum state",Nature Physics 8, 475–478 (2012) doi:10.1038/nphys2309
- Reich, Eugenie Samuel (17 November 2011). "Quantum theorem shakes foundations". Nature. doi:10.1038/nature.2011.9392. Retrieved 20 November 2011.
- Pusey, Matthew F.; Barrett, Jonathan; Rudolph, Terry (2012). "On the reality of the quantum state". arXiv:1111.3328v2 [quant-ph].
- 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.
- Matt Pusey (30 November 2011). "Matthew Pusey at Imperial College". Imperial College London. Retrieved 30 November 2011.