by Staff Writers
Calgary, Canada (SPX) Jul 12, 2012
Many of the predictions we make in everyday life are vague, and we often get them wrong because we have incomplete information, such as when we predict the weather. But in quantum mechanics, even if all the information is available, the outcomes of certain experiments generally can't be predicted perfectly beforehand.
This inability to accurately predict the results of experiments in quantum physics has been the subject of a long debate, going back to Einstein and co-workers, about whether quantum mechanics is the best way to predict outcomes.
Researchers from the University of Calgary's Institute for Quantum Information Science along with researchers from the Perimeter Institute in Waterloo and the Eidgenossische Technische Hochschule (ETH) in Zurich/Switzerland have published a paper in Physics Review Letters that suggests quantum theory is close to optimal in terms of its predictive power.
The research in this paper looks at measurements on members of maximally entangled pairs of photons that are sent into Stern-Gerlach-type apparatus, in which each photon can take one out of two possible paths.
"In our experiment, we show that any theory in which there is significantly less randomness is destined to fail: quantum theory essentially provides the ultimate bound on how predictable the universe is," says Dr. Wolfgang Tittel, associate professor and GDC/AITFIndustrial Research Chair in Quantum Cryptography and Communicationat the University of Calgary.
Dr. Renato Renner, Professor at the ETH in Zurich adds: "In other words, not only does God 'play dice,' but his dice are fair."
Randomness in quantum theory is one of its key features and is widely known, even outside the scientific community, says Tittel. "Its appeal is its fundamental nature and broad range of implications: knowing the precise configuration of the universe at the big bang would not be sufficient to predict its entire evolution, for example, in contrast to classical theory."
The paper: "An experimental bound on the maximum predictive power of physical theories" is by Terence E. Stuart,Joshua A. Slater, Roger Colbeck, Renato Renner and Wolfgang Tittel is available here.
University of Calgary
Understanding Time and Space
Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.
A new particle has been discovered - chances are, it is the Higgs boson
Tel Aviv, Israel (SPX) Jul 05, 2012
The long and complicated journey to detect the Higgs boson, which started with one small step about 25 years ago, might finally have reached its goal. This was reported by LHC particle accelerator scientists at the European Laboratory for Particle Physics, CERN, near Geneva. The Higgs boson is the final building block that has been missing from the "Standard Model," which describes the str ... read more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|