Quantum Physicists and Gamers Challenge Local Realism

Griffith University researchers have played an important role in a major international collaboration that tested quantum non-locality – Einstein’s “spooky action at a distance” – in a suite of experiments worldwide. The joint work of the “Big Bell Test” (BBT) consortium, published in Nature, used random numbers sourced from people’s free will to rigorously ensure unpredictability in the measurement settings required for such tests. The project used an online game through which members of the public provided random numbers to the experiments in real time. Thus, the project is a flagship for new approaches to citizen involvement in science, and for science outreach.

The Griffith University team, led by Dr Raj Patel and Professor Geoff Pryde, performed a test of "quantum steering” as part of the BBT. Steering is a practical form of quantum non-locality testing that is resistant to real-world device imperfections, and has direct application to quantum communication tasks such as verifying that entanglement has been shared between remote parties. Pryde said, “One of the things that was exciting and really interesting for us was to be part of a big project that required a large amount of coordination. From compiling random numbers from the public to disseminating them between the experiments, and receiving and using them in a timely way, the level of collaboration was remarkable. I also particularly enjoyed the outreach and public involvement side; I enjoyed that we gave people an opportunity to do something which influenced how the experiment ran.”

Einstein-Podolsky-Rosen steering experiment at Griffith

Professor Geoff Pryde explains the Big Bell Test

Nonlocal effects such as entanglement underlie the quantum computation and communication science technologies being pursued at Griffith University and in other teams in the Australian Research Council Centre of Excellence for Quantum Computation and Communication Technology. These technologies promise to bring major advances to information processing and networking in the 21st century.


Journal Reference:

Challenging local realism with human choices, The Big Bell Test Collaboration, Nature 557, 212–216 (2018) doi:10.1038/s41586-018-0085-3

Image Courtesy: Dr Raj Patel

Want to know more?

Contact the Centre for Quantum Dynamics