Featured Research

from universities, journals, and other organizations

Particle and wave-like behavior of light measured simultaneously

Date:
November 1, 2012
Source:
University of Bristol
Summary:
What is light made of: waves or particles? This basic question has fascinated physicists since the early days of science. Quantum mechanics predicts that photons, particles of light, are both particles and waves simultaneously. Physicists now give a new demonstration of this wave-particle duality of photons, dubbed the "one real mystery of quantum mechanics" by Nobel Prize laureate Richard Feynman.

Quantum mechanics predicts that photons, particles of light, are both particles and waves simultaneously. Physicists now give a new demonstration of this wave-particle duality of photons.
Credit: Yahya Idiz / Fotolia

What is light made of: waves or particles? This basic question has fascinated physicists since the early days of science. Quantum mechanics predicts that photons, particles of light, are both particles and waves simultaneously. Reporting in Science, physicists from the University of Bristol give a new demonstration of this wave-particle duality of photons, dubbed the 'one real mystery of quantum mechanics' by Nobel Prize laureate Richard Feynman.

Related Articles


The history of science is marked by an intense debate between the particle and wave theories of light. Isaac Newton was the main advocate of the particle theory, while James Clerk Maxwell and his greatly successful theory of electromagnetism, gave credit to the wave theory. However, things changed dramatically in 1905, when Einstein showed that it was possible to explain the photoelectric effect (which had remained a complete mystery until then) using the idea that light is made of particles: photons. This discovery had a huge impact on physics, as it greatly contributed to the development of quantum mechanics -- the most accurate scientific theory ever developed.

Despite its success, quantum mechanics presents a tremendous challenge to our everyday intuition. Indeed, the theory predicts with a remarkable accuracy the behaviour of small objects such as atoms and photons. However, when taking a closer look at these predictions, we are forced to admit that they are strikingly counter-intuitive. For instance, quantum theory predicts that a particle (for instance a photon) can be in different places at the same time. In fact it can even be in infinitely many places at the same time, exactly as a wave. Hence the notion of wave-particle duality, which is fundamental to all quantum systems.

Surprisingly, when a photon is observed, it behaves either as a particle or as a wave. But both aspects are never observed simultaneously. In fact, which behaviour it exhibits depends on the type of measurement it is presented with. These astonishing phenomena have been experimentally investigated in the last few years, using measurement devices that can be switched between wave-like and particle-like measurements.

In a paper published Nov. 1 in Science, physicists from the University of Bristol give a new twist on these ideas. Dr Alberto Peruzzo, Peter Shadbolt and Professor Jeremy O'Brien from the Centre for Quantum Photonics teamed up with quantum theorists Dr Nicolas Brunner and Professor Sandu Popescu to devise a novel type of measurement apparatus that can measure both particle and wave-like behaviour simultaneously. This new device is powered by quantum nonlocality, another strikingly counter-intuitive quantum effect.

Dr Peruzzo, Research Fellow at the Centre for Quantum Photonics, said: "The measurement apparatus detected strong nonlocality, which certified that the photon behaved simultaneously as a wave and a particle in our experiment. This represents a strong refutation of models in which the photon is either a wave or a particle."

Professor O'Brien, Director of the Centre for Quantum Photonics, said: "To conduct this research, we used a quantum photonic chip, a novel technology pioneered in Bristol. The chip is reconfigurable so it can be programmed and controlled to implement different circuits. Today this technology is a leading approach in the quest to build a quantum computer and in the future will allow for new and more sophisticated studies of fundamental aspects of quantum phenomena."


Story Source:

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


Journal Reference:

  1. Alberto Peruzzo, Peter Shadbolt, Nicolas Brunner, Sandu Popescu, and Jeremy L. O’Brien. A Quantum Delayed-Choice Experiment. Science, 2012; 338 (6107): 634-637 DOI: 10.1126/science.1226719

Cite This Page:

University of Bristol. "Particle and wave-like behavior of light measured simultaneously." ScienceDaily. ScienceDaily, 1 November 2012. <www.sciencedaily.com/releases/2012/11/121101141107.htm>.
University of Bristol. (2012, November 1). Particle and wave-like behavior of light measured simultaneously. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2012/11/121101141107.htm
University of Bristol. "Particle and wave-like behavior of light measured simultaneously." ScienceDaily. www.sciencedaily.com/releases/2012/11/121101141107.htm (accessed October 31, 2014).

Share This



More Matter & Energy News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Jaguar Land Rover Opens $800 Million Factory in Britain

Jaguar Land Rover Opens $800 Million Factory in Britain

AFP (Oct. 30, 2014) British luxury car manufacturer Jaguar Land Rover opened a $800 million engine manufacturing centre in western England, creating 1,400 jobs. Duration: 00:45 Video provided by AFP
Powered by NewsLook.com
SkyCruiser Concept Claims to Solve Problem With Flying Cars

SkyCruiser Concept Claims to Solve Problem With Flying Cars

Buzz60 (Oct. 30, 2014) A start-up company called Krossblade says its SkyCruiser concept flying car solves the problem with most flying car concepts. Mara Montalbano (@maramontalbano) explains. Video provided by Buzz60
Powered by NewsLook.com
Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Reuters - Innovations Video Online (Oct. 29, 2014) A Swedish amputee who became the first person to ever receive a brain controlled prosthetic arm is able to manipulate and handle delicate objects with an unprecedented level of dexterity. The device is connected directly to his bone, nerves and muscles, giving him the ability to control it with his thoughts. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Robots Get Funky on the Dance Floor

Robots Get Funky on the Dance Floor

AP (Oct. 29, 2014) Dancing, spinning and fighting robots are showing off their agility at "Robocomp" in Krakow. (Oct. 29) Video provided by AP
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