PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Feynman's double-slit experiment brought to life

2013-03-14
(Press-News.org) The precise methodology of Richard Feynman's famous double-slit thought-experiment – a cornerstone of quantum mechanics that showed how electrons behave as both a particle and a wave – has been followed in full for the very first time.

Although the particle-wave duality of electrons has been demonstrated in a number of different ways since Feynman popularised the idea in 1965, none of the experiments have managed to fully replicate the methodology set out in Volume 3 of Feynman's famous Lectures on Physics.

"The technology to do this experiment has been around for about two decades; however, to do a nice data recording of electrons takes some serious effort and has taken us three years," said lead author of the study Professor Herman Batelaan from the University of Nebraska-Lincoln.

"Previous double-slit experiments have successfully demonstrated the mysterious properties of electrons, but none have done so using Feynman's methodology, specifically the opening and closing of both slits at will and the ability to detect electrons one at a time.

"Akira Tonomura's brilliant experiment used a thin, charged wire to split electrons and bring them back together again, instead of two slits in a wall which was proposed by Feynman. To the best of my knowledge, the experiments by Guilio Pozzi were the first to use nano-fabricated slits in a wall; however, the slits were covered up by stuffing them with material so could not be open and closed automatically."

In their experiments, which have been published today, Thursday 14 March, in the Institute of Physics and German Physical Society's New Journal of Physics, Batelaan and his team, along with colleagues at the Perimeter Institute of Theoretical Physics, created a modern representation of Feynman's experiment by directing an electron beam, capable of firing individual electrons, at a wall made of a gold-coated silicon membrane.

The wall had two 62-nm-wide slits in it with a centre-to-centre separation of 272 nm. A 4.5 µm wide and 10 µm tall moveable mask, controlled by a piezoelectric actuator, was placed behind the wall and slid back and forth to cover the slits.

"We've created an experiment where both slits can be mechanically opened and closed at will and, most importantly, combined this with the capability of detecting one electron at a time.

"It is our task to turn every stone when it comes to the most fundamental experiments that one can do. We have done exactly that with Feynman's famous thought-experiment and have been able to illustrate the key feature of quantum mechanics," continued Batelaan.

Feynman's double-slit experiment

In Feynman's double-slit thought-experiment, a specific material is randomly directed at a wall which has two small slits that can be opened and closed at will – some of the material gets blocked and some passes through the slits, depending on which ones are open.

Based on the pattern that is detected beyond the wall on a backstop – which is fitted with a detector – one can discern whether the material coming through behaves as either a wave or particle.

When particles are fired at the wall with both slits open, they are more likely to hit the backstop in one particular area, whereas waves interfere with each other and hit the backstop at a number of different points with differing strength, creating what is known as an interference pattern.

In 1965, Feynman popularised that electrons – historically thought to be particles – would actually produce the pattern of a wave in the double-split experiment.

Unlike sound waves and water waves, Feynman highlighted that when electrons are fired at the wall one at a time, an interference pattern is still produced. He went on to say that this phenomenon "has in it the heart of quantum physics [but] in reality, it contains the only mystery."

###From Thursday 14 March, this paper can be downloaded from http://iopscience.iop.org/1367-2630/15/3/033018/article

Notes to Editors

Contact

1. For further information, a full draft of the journal paper or to contact one of the researchers, contact IOP Press Officer, Michael Bishop:
Tel: 0117 930 1032
E-mail: Michael.Bishop@iop.org

IOP Publishing Journalist Area

2. The IOP Publishing Journalist Area (http://journalists.iop.org/journalistLogin) gives journalists access to embargoed press releases, advanced copies of papers, supplementary images and videos. In addition to this, a weekly news digest is uploaded into the Journalist Area every Friday, highlighting a selection of newsworthy papers set to be published in the following week.

Login details also give free access to IOPscience, IOP Publishing's journal platform.

To apply for a free subscription to this service, please email Michael Bishop, IOP Press Officer, michael.bishop@iop.org, with your name, organisation, address and a preferred username.

Controlled double-slit electron diffraction

3. The published version of the paper "Controlled double-slit electron diffraction" (Roger Bach et al 2013 New J. Phys. 15 033018) will be freely available online from Thursday 14 March at http://iopscience.iop.org/1367-2630/15/3/033018/article.

New Journal of Physics

4. New Journal of Physics publishes across the whole of physics, encompassing pure, applied, theoretical and experimental research, as well as interdisciplinary topics where physics forms the central theme. All content is permanently free to read and the journal is funded by an article publication charge.

IOP Publishing

5. IOP Publishing provides publications through which leading-edge scientific research is distributed worldwide. IOP Publishing is central to the Institute of Physics (IOP), a not-for-profit society. Any financial surplus earned by IOP Publishing goes to support science through the activities of IOP. Beyond our traditional journals programme, we make high-value scientific information easily accessible through an ever-evolving portfolio of community websites, magazines, conference proceedings and a multitude of electronic services. Focused on making the most of new technologies, we're continually improving our electronic interfaces to make it easier for researchers to find exactly what they need, when they need it, in the format that suits them best. Go to http://ioppublishing.org/

The Institute of Physics

6. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 45,000, working together to advance physics education, research and application. We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.

The German Physical Society

7. The German Physical Society (DPG), with a tradition extending back to 1845, is the largest physical society in the world with more than 59,000 members. The DPG sees itself as the forum and mouthpiece for physics and is a non-profit organisation that does not pursue financial interests. It supports the sharing of ideas and thoughts within the scientific community, fosters physics teaching and would also like to open a window to physics for all those with a healthy curiosity.


ELSE PRESS RELEASES FROM THIS DATE:

No attention-boosting drugs for healthy kids, doctors urge

2013-03-14
Doctors at Yale School of Medicine and the American Academy of Neurology (AAN) have called upon their fellow physicians to limit or end the practice of prescribing memory-enhancing drugs to healthy children whose brains are still developing. Their position statement is published in the March 13 online issue of the journal Neurology, the medical journal of the AAN. The statement was written to address the growing trend in which teens use "study drugs" before tests and parents request attention deficit hyperactivity disorder (ADHD) drugs for children who don't meet the ...

Strange phallus-shaped creature provides crucial missing link

Strange phallus-shaped creature provides crucial missing link
2013-03-14
This press release is available in French. Christopher Cameron of the University of Montreal's Department of Biological Sciences and his colleagues have unearthed a major scientific discovery - a strange phallus-shaped creature they found in Canada's Burgess Shale fossil beds, located in Yoho National Park. The fossils were found in an area of shale beds that are 505 million years old. Their study, to be published online in the journal Nature on March 13, 2013, confirms Spartobranchus tenuis is a member of the acorn worms group which are seldom-seen animals that thrive ...

Burgess Shale worm provides crucial missing link

2013-03-14
Canada's 505 million year-old Burgess Shale fossil beds, located in Yoho National Park, have yielded yet another major scientific discovery – this time with the unearthing of a strange phallus-shaped creature. A study to be published online in the journal Nature on March 13 confirms Spartobranchus tenuis is a member of the acorn worms group which are seldom-seen animals that thrive today in the fine sands and mud of shallow and deeper waters. Acorn worms are themselves part of the hemichordates, a group of marine animals closely related to today's sea stars and sea ...

NIST mechanical micro-drum used as quantum memory

NIST mechanical micro-drum used as quantum memory
2013-03-14
BOULDER, Colo.— One of the oldest forms of computer memory is back again—but in a 21st century microscopic device designed by physicists at the National Institute of Standards and Technology (NIST) for possible use in a quantum computer. The NIST team has demonstrated that information encoded as a specific point in a traveling microwave signal—the vertical and horizontal positions of a wave pattern at a certain time—can be transferred to the mechanical beat of a micro-drum and later retrieved with 65 percent efficiency, a good figure for experimental systems like this. ...

ALMA rewrites history of Universe's stellar baby boom

ALMA rewrites history of Universes stellar baby boom
2013-03-14
Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) show that the most vigorous bursts of star birth in the cosmos took place much earlier than previously thought. The results are published in a set of papers to appear in the journal Nature and in the Astrophysical Journal. The research is the most recent example of the discoveries coming from the new international ALMA observatory, which celebrates its inauguration today. The most intense bursts of star birth are thought to have occurred in the early Universe, in massive, bright galaxies. These ...

New MRI method fingerprints tissues and diseases

2013-03-14
A new method of magnetic resonance imaging (MRI) could routinely spot specific cancers, multiple sclerosis, heart disease and other maladies early, when they're most treatable, researchers at Case Western Reserve University and University Hospitals (UH) Case Medical Center suggest in the journal Nature. Each body tissue and disease has a unique fingerprint that can be used to quickly diagnose problems, the scientists say. By using new MRI technologies to scan for different physical properties simultaneously, the team differentiated white matter from gray matter from ...

Joslin scientists discover mechanism that regulates production of energy-burning brown fat

Joslin scientists discover mechanism that regulates production of energy-burning brown fat
2013-03-14
BOSTON – March 13, 2013 – Joslin scientists have discovered a mechanism that regulates the production of brown fat, a type of fat which plays an important role in heat production and energy metabolism. The findings, which appear in the upcoming issue of Nature, may lead to new therapies that increase BAT formation to treat obesity. Two types of fat tissue are present in humans and other mammals: white adipose tissue (WAT) or white fat, which stores fat; and brown adipose tissue (BAT) or brown fat, which burns fat to produce heat. Brown fat also metabolizes glucose and ...

Tobacco industry appears to have evaded FDA ban on 'light' cigarette descriptors

2013-03-14
Boston, MA – New research from Harvard School of Public Health (HPSH) shows that one year after the federal government passed a law banning word descriptors such as "light," "mild," and "low" on cigarette packages, smokers can still easily identify their brands because of color-coding that tobacco companies added to "light" packs after the ban. These findings suggest that the companies have, in effect, been able to evade the ban on misleading wording—thus still conveying the false and deceptive message that lights are safer than "regular" cigarettes. In addition, the ...

Ancient, highly active galaxies discovered

2013-03-14
Pasadena, CA — Using information gathered from several telescopes, a team of astronomers, including Carnegie's Eric Murphy, searched the sky for very rarely seen dusty starburst galaxies, formed soon after the Big Bang. These galaxies are characterized by an unusually high rate of star formation. They are much more abundant in the early Universe than previously thought. Two of those identified are among the oldest ever found, indicating that these dusty starbursts likely evolve into the most massive galaxies ever observed in the local Universe. The results are published ...

ALMA finds 'monster' starburst galaxies in the early universe

2013-03-14
Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope have discovered starburst galaxies earlier in the Universe's history than they were previously thought to have existed. These newly discovered galaxies represent what today's most massive galaxies looked like in their energetic, star-forming youth. The research is the most recent example of the discoveries coming from the new international ALMA observatory, which celebrates its inauguration today. The results, published in a set of papers to appear in the journal Nature and in the Astrophysical ...

LAST 30 PRESS RELEASES:

Animated movie characters with strabismus are more likely to be villains, study finds

How retailers change ordering strategy when a supplier starts its own direct channel

Young coral use metabolic tricks to resist bleaching

Protecting tax whistleblowers pays off

Bioluminescent proteins made from scratch enable non-invasive, multi-functional biological imaging

New study links air pollution with higher rates of head and neck cancer

LSU researchers excavate earliest ancient Maya salt works

Building a diverse wildland fire workforce to meet future challenges

MBARI researchers discover remarkable new swimming sea slug in the deep sea

Decentralized social media ‘increases citizen empowerment’, says Oxford study

Validating an electronic frailty index in a national health system

Combination approach shows promise for treating rare, aggressive cancers

Raise the roof: How to reduce badminton birdie drift

Ouch! Commonalties found in pain vocalizations and interjections across cultures

Income-related disparities in mortality among young adults with type 2 diabetes

Medical board discipline of physicians for spreading medical misinformation

First-ever randomized clinical trial uses telehealth for suicide prevention

DNA packaging directly affects how fast DNA is copied in cells

Scientists develop advanced catalyst for self-driven seawater splitting with enhanced chloride resistance

City of Hope researchers discover why taking a mushroom supplement slows or prevents prostate cancer from getting worse

Montefiore Einstein’s Marina Konopleva joins Break Through Cancer TeamLab in fight against acute myelogenous leukemia

Early treatment for nerve tumors prevents serious problems, study finds

Study: Student absenteeism crisis may be hurting teacher job satisfaction

Medicaid enrollment continuity tied to lymphoma stage at diagnosis

INSEAD launches free Negotiation Course for the World

Wyss Institute’s iNodes team receives ARPA-H Sprint for Women’s Health award to advance the first implantable immune organs to treat ovarian cancer

Goblet cells could be the guardians of the gut

Romania’s science journalists join forces on new reporting handbook 

SwRI-led team proposes new solar composition ratios that could reconcile longstanding questions

Sodium butyrate inhibits necroptosis by regulating MLKL via E2F1 in intestinal epithelial cells of liver cirrhosis

[Press-News.org] Feynman's double-slit experiment brought to life