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 Eidgenössische Technische Hochschule (ETH) in Zürich/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 Zürich 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: http://prl.aps.org/abstract/PRL/v109/i2/e020402
Leanne Yohemas | EurekAlert!
Only an atom thick: Physicists succeed in measuring mechanical properties of 2D monolayer materials
17.01.2018 | Universität des Saarlandes
Black hole spin cranks-up radio volume
15.01.2018 | National Institutes of Natural Sciences
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
18.01.2018 | Life Sciences
18.01.2018 | Life Sciences
18.01.2018 | Earth Sciences