Featured Research

from universities, journals, and other organizations

More precision from less predictability: A new quantum trade-off

Date:
May 29, 2013
Source:
Griffith University
Summary:
Researchers in Australia have demonstrated that, contrary to what the Heisenberg uncertainty relation may suggest, particle properties such as position and momentum can be measured simultaneously with high precision. But it comes at a cost.

Researchers at Griffith University's Centre for Quantum Dynamics have demonstrated that, contrary to what the Heisenberg uncertainty relation may suggest, particle properties such as position and momentum can be measured simultaneously with high precision.

But it comes at a cost.

The findings have been published in Experimental Test of Universal Complementarity Relations in the journal Physical Review Letters.

Co-author Dr Michael Hall said the work represents an important advance in the quantitative understanding and experimental verification of complementarity; arguably the most important foundational principle of quantum mechanics.

"Quantum mechanics is often thought to imply that you can estimate precisely how fast an electron is moving, or exactly where it is, but not both at the same time," Dr Hall said.

"The argument is that properties such as speed and position require physically incompatible or 'complementary' devices for their precise measurement and therefore, any device used to make a simultaneous measurement will give inherently imprecise estimates," he said.

"This argument was challenged by Einstein in 1935, who gave an example where the position and speed could be measured accurately at the same time, by exploiting quantum correlations with a second particle."

Professor Geoff Pryde, co-author and leader of the experimental team, said it is important to note that this is not in direct conflict with the well-known Heisenberg uncertainty relation, which requires only that the position and speed cannot both be predicted accurately beforehand, but it does leave open the important question of whether any quantum restrictions apply to simultaneous measurements.

"We have verified experimentally that Einstein was correct by using polarisation properties of photons rather than position and speed," Professor Pryde said.

"But we have also shown that a high degree of joint precision does not come for free; it is possible only if the measurement outcomes are sufficiently unpredictable, as quantified by a new generalisation of the Heisenberg uncertainty relation.

"As the uncertainty principle underlies many aspects of quantum information technology, ranging from entanglement verification to random number generation to the security of quantum cryptography, our work could have implications in all these areas."


Story Source:

The above story is based on materials provided by Griffith University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Morgan M. Weston, Michael J. W. Hall, Matthew S. Palsson, Howard M. Wiseman, Geoff J. Pryde. Experimental Test of Universal Complementarity Relations. Physical Review Letters, 2013; 110 (22) DOI: 10.1103/PhysRevLett.110.220402

Cite This Page:

Griffith University. "More precision from less predictability: A new quantum trade-off." ScienceDaily. ScienceDaily, 29 May 2013. <www.sciencedaily.com/releases/2013/05/130529191041.htm>.
Griffith University. (2013, May 29). More precision from less predictability: A new quantum trade-off. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2013/05/130529191041.htm
Griffith University. "More precision from less predictability: A new quantum trade-off." ScienceDaily. www.sciencedaily.com/releases/2013/05/130529191041.htm (accessed October 22, 2014).

Share This



More Matter & Energy News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
China Airlines Swanky New Plane

China Airlines Swanky New Plane

Buzz60 (Oct. 21, 2014) China Airlines debuted their new Boeing 777, and it's more like a swanky hotel bar than an airplane. Enjoy high-tea, a coffee bar, and a full service bar with cocktails and spirits, and lie-flat in your reclining seats. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins