Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > More certainty on uncertainty's quantum mechanical role: Researchers present findings at Frontiers in Optics 2012 that observation need not disturb systems as much as once thought, severing the act of measurement from the Heisenberg Uncertainty Principle

A general method for measuring the precision and disturbance of any system. The system is weakly measured before the measurement apparatus and then strongly measured afterwards.

Credit: Lee Rozema, University of Toronto
A general method for measuring the precision and disturbance of any system. The system is weakly measured before the measurement apparatus and then strongly measured afterwards.

Credit: Lee Rozema, University of Toronto

Abstract:
Scientists who study the ultra-small world of atoms know it is impossible to make certain simultaneous measurements, for example finding out both the location and momentum of an electron, with an arbitrarily high level of precision. Because measurements disturb the system, increased certainty in the first measurement leads to increased uncertainty in the second. The mathematics of this unintuitive concept - a hallmark of quantum mechanics - were first formulated by the famous physicist Werner Heisenberg at the beginning of the 20th century and became known as the Heisenberg Uncertainty Principle. Heisenberg and other scientists later generalized the equations to capture an intrinsic uncertainty in the properties of quantum systems, regardless of measurements, but the uncertainty principle is sometimes still loosely applied to Heisenberg's original measurement-disturbance relationship. Now researchers from the University of Toronto have gathered the most direct experimental evidence that Heisenberg's original formulation is wrong. The results were published online in the journal Physical Review Letters last month and the researchers will present their findings for the first time at the Optical Society's (OSA) Annual Meeting, Frontiers in Optics (FiO), taking place in Rochester, N.Y. Oct. 14 -18.

More certainty on uncertainty's quantum mechanical role: Researchers present findings at Frontiers in Optics 2012 that observation need not disturb systems as much as once thought, severing the act of measurement from the Heisenberg Uncertainty Principle

Washington, DC | Posted on October 4th, 2012

The Toronto team set up an apparatus to measure the polarization of a pair of entangled photons. The different polarization states of a photon, like the location and momentum of an electron, are what are called complementary physical properties, meaning they are subject to the generalized Heisenberg uncertainty relationship. The researchers' main goal was to quantify how much the act of measuring the polarization disturbed the photons, which they did by observing the light particles both before and after the measurement. However, if the "before shot" disturbed the system, the "after shot" would be tainted.

The researchers found a way around this quantum mechanical Catch-22 by using techniques from quantum measurement theory to sneak non-disruptive peeks of the photons before their polarization was measured. "If you interact very weakly with your quantum particle, you won't disturb it very much," explained Lee Rozema, a Ph.D. candidate in quantum optics research at the University of Toronto, and lead author of the study. Weak interactions, however, can be like grainy photographs: they yield very little information about the particle. "If you take just a single measurement, there will be a lot of noise in that measurement," said Rozema. "But if you repeat the measurement many, many times, you can build up statistics and can look at the average."

By comparing thousands of "before" and "after" views of the photons, the researchers revealed that their precise measurements disturbed the system much less than predicted by the original Heisenberg formula. The team's results provide the first direct experimental evidence that a new measurement-disturbance relationship, mathematically computed by physicist Masanao Ozawa, at Nagoya University in Japan, in 2003, is more accurate.

"Precision quantum measurement is becoming a very important topic, especially in fields like quantum cryptography where we rely on the fact that measurement disturbs the system in order to transmit information securely," said Rozema. "In essence, our experiment shows that we are able to make more precise measurements and give less disturbance than we had previously thought."

Presentation FW4J.4, "Direct Violation of Heisenberg's Precision Limit by Weak Measurements," takes place Wednesday, Oct. 17 at 2:30 p.m. EDT at the Rochester Riverside Convention Center in Rochester, N.Y.

PRESS REGISTRATION: A press room for credentialed press and analysts will be located in the Rochester Riverside Convention Center, Sunday through Thursday, Oct. 14-18. Those interested in obtaining a press badge for FiO should contact OSA's Angela Stark at 202.416.1443 or .

####

About Optical Society of America
Uniting more than 180,000 professionals from 175 countries, the Optical Society (OSA) brings together the global optics community through its programs and initiatives. Since 1916 OSA has worked to advance the common interests of the field, providing educational resources to the scientists, engineers and business leaders who work in the field by promoting the science of light and the advanced technologies made possible by optics and photonics. OSA publications, events, technical groups and programs foster optics knowledge and scientific collaboration among all those with an interest in optics and photonics.

About the Meeting

Frontiers in Optics (FiO) 2012 is the Optical Society's (OSA) 96th Annual Meeting and is being held together with Laser Science XXVIII, the annual meeting of the American Physical Society (APS) Division of Laser Science (DLS). The two meetings unite the OSA and APS communities for five days of quality, cutting-edge presentations, fascinating invited speakers and a variety of special events spanning a broad range of topics in optics and photonics—the science of light—across the disciplines of physics, biology and chemistry. FiO 2012 will also offer a number of Short Courses designed to increase participants' knowledge of a specific subject in the optical sciences while offering the experience of insightful teachers. An exhibit floor featuring leading optics companies will further enhance the meeting. More information at www.FrontiersinOptics.org.

For more information, please click here

Contacts:
Angela Stark

202-416-1443

Copyright © Optical Society of America

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Pixel-array quantum cascade detector paves the way for portable thermal imaging devices: Research team from TU-Wien Center for Micro- and Nanostructures have developed a new 'cooler' sensing instrument thereby increasing energy-efficiency and enhancing mobility for diagnostic tes July 28th, 2016

Dirty to drinkable: Engineers develop novel hybrid nanomaterials to transform water July 28th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Physics

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Attosecond physics: Mapping electromagnetic waveforms July 25th, 2016

Entanglement: Chaos - Researchers at UCSB blur the line between classical and quantum physics by connecting chaos and entanglement July 14th, 2016

Physicists couple distant nuclear spins using a single electron: For the first time, researchers at the University of Basel have coupled the nuclear spins of distant atoms using just a single electron July 12th, 2016

Discoveries

Pixel-array quantum cascade detector paves the way for portable thermal imaging devices: Research team from TU-Wien Center for Micro- and Nanostructures have developed a new 'cooler' sensing instrument thereby increasing energy-efficiency and enhancing mobility for diagnostic tes July 28th, 2016

Dirty to drinkable: Engineers develop novel hybrid nanomaterials to transform water July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Announcements

Pixel-array quantum cascade detector paves the way for portable thermal imaging devices: Research team from TU-Wien Center for Micro- and Nanostructures have developed a new 'cooler' sensing instrument thereby increasing energy-efficiency and enhancing mobility for diagnostic tes July 28th, 2016

Dirty to drinkable: Engineers develop novel hybrid nanomaterials to transform water July 28th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Events/Classes

Nanometrics Announces Upcoming Investor Events July 20th, 2016

n-tech Research Announces August 3, 2016 Date for Smart Coatings Webinar July 18th, 2016

Instrumented Indentation Expert Addresses Trends with Industry Leaders: Leading nanoindentation expert hosts webinar discussing theory and practice of instrumented indentation July 14th, 2016

SUNY Poly Celebrates Its 10th Year Exhibiting at SEMICON West with Cutting Edge Developments in Integrated Photonics and Power Electronics July 8th, 2016

Photonics/Optics/Lasers

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Attosecond physics: Mapping electromagnetic waveforms July 25th, 2016

RMIT researchers make leap in measuring quantum states July 21st, 2016

The birth of quantum holography: Making holograms of single light particles! July 21st, 2016

Quantum nanoscience

Quantum drag:University of Iowa physicist says current in one iron magnetic sheet can create quantized spin waves in another, separate sheet July 22nd, 2016

A new spin on reality July 15th, 2016

Physicists couple distant nuclear spins using a single electron: For the first time, researchers at the University of Basel have coupled the nuclear spins of distant atoms using just a single electron July 12th, 2016

Quantum technologies to revolutionize 21st century: Nobel Laureates to discuss impacts at 66th Lindau Meeting July 5th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic