October 8, 2013
For Immediate Release
Contacts:
Michael Turner
APS President
312-330-4627 (Cell)
James Riordon
APS Media Relations
riordon@aps.org
301-209-3238
2013 Physics Nobel for Discovery of the Higgs Boson and the Symmetry Breaking Theory that Predicted It
College Park, MD – The 2013 Physics Nobel Prize has been awarded to two physicists who were instrumental in developing the theory that helps explain the origin of mass of elementary particles and predicts the existence of the Higgs Boson discovered last year. The prize, which recognizes the contributions of Francois Englert (Universite Libre de Bruxelles) and Peter Higgs (University of Edinburgh) for the theory of broken symmetry in electroweak physics, echoes the announcement of the 2010 American Physical Society’s J. J. Sakurai prize, which was awarded to the two Nobel Laureates as well as four additional physicists who made comparable contributions to the symmetry breaking work.
"The discovery of the Higgs boson has captured the imagination of physicists and the public alike," said American Physical Society president Michael Turner. "It is hard to find a cab driver anywhere in the world who when he knows you are physicist doesn't ask about the Higgs boson. This is a tremendous achievement, involving more than 10,000 physicists from the around the world to build, operate and analyze data from the most complex and most expensive science experiment ever built. The discovery of this new class of elementary particles not only completes one of the great intellectual achievements of the last century -- the standard model of particle physics -- but also raises new questions and has implications for other areas of physics including the birth of the Universe. Hats off to the global village of physicists who made this grand discovery possible, from Peter Higgs and Francois Englert to the thousands of scientists working at CERN --- many from the US and many not even born when Higgs wrote his paper. The particle is truly worthy of the name that Leon Lederman gave it -- the god particle."
The landmark papers the Laureates published that laid the foundation for spontaneous symmetry breaking appeared in the flagship APS journal Physical Review Letters in 1964. Both papers are available free-to-read to the general public.
Broken Symmetry and the Mass of Gauge Vector Mesons
F. Englert and R. Brout
Phys. Rev. Lett. 13, 321 (1964)
http://prl.aps.org/pdf/PRL/v13/i9/p321_1
Broken Symmetries and the Masses of Gauge Bosons
Peter W. Higgs
Phys. Rev. Lett. 13, 508 (1964)
http://prl.aps.org/pdf/PRL/v13/i16/p508_1
"We congratulate the Laureates and all who have contributed to this marvelous triumph for physics," said APS Editor in Chief Gene Sprouse. "APS is proud to have published the seminal papers that have led to this year's Nobel Prize."
The 2010 APS Sakurai prize cited Robert Brout (Universite Libre de Bruxelles), Gerald S. Guralnik (Brown University), Carl R. Hagen (University of Rochester), and T.W.B. Kibble (Imperial College) along with Englert and Higgs because the contributions of all six physicists were instrumental to the development of the highly successful standard theory of physics. In fact, Steven Weinberg (1979 Physics Nobel Laureate) cited them all on equal footing in his landmark paper “A Model of Leptons.”
“It’s unfortunate that the Nobel Prize is limited to only two recipients,” said R. Sekhar Chivukula (2010 chair of the APS Sakurai Prize Selection Committee), “because failing to recognize the work of Guralnik, Hagen and Kibble is a significant oversight. I’m glad that the APS could award a prestigious prize in a way that makes clear just how important they all were in establishing the foundations of contemporary particle physics.”
The 2010 Sakurai Prize cites Guralnik, Hagen, Kibble, Brout, Englert, and Higgs for “elucidation of the properties of spontaneous symmetry breaking in four-dimensional relativistic gauge theory and of the mechanism for the consistent generation of vector boson masses"
More information about the Sakurai prize is available at www.aps.org/programs/honors/prizes/sakurai.cfm
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About APS
The American Physical Society (www.aps.org) is a non-profit membership organization working to advance and diffuse the knowledge of physic through its outstanding research journals, scientific meetings, and education, outreach, advocacy and international activities. APS represents over 50,000 members, including physicists in academia, national laboratories and industry in the United States and throughout the world. Society offices are located in College Park, MD (Headquarters), Ridge, NY, and Washington, DC.
Tuesday, October 8, 2013
Tuesday, October 1, 2013
APS Physics Tip Sheet – Sep 30, 2013: The Weak Side of the Proton, Finding New Superconductors, Trapping Atoms in Magnetic Vortices
APS Physics Tip Sheet – Sep 30, 2013
In this issue: The Weak Side of the Proton, Finding New Superconductors, Trapping Atoms in Magnetic Vortices
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The Weak Side of the Proton
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An international collaboration has measured for the first time the weak charge of the proton – the parameter characterizing the strength of its interaction with the weak force.
In the same way that the electric charge of a particle determines the response to an electromagnetic force, the so-called "weak charge" characterizes the strength of the “weak force” – the fundamental interaction responsible for radioactive decay or nuclear fusion. The weak charge is hard to measure, since its effects outside the sub-atomic world are masked by the stronger electromagnetic interaction. Now, the Qweakcollaboration has measured the proton’s weak charge using a spin-polarized electron beam at the Thomas Jefferson National Accelerator Facility in Virginia. By analyzing how the beam was scattered by the protons contained in liquid hydrogen, the researchers were able to determine the proton’s weak charge, finding a value in good agreement with the theoretical prediction of the standard model.
* Qweak collaboration (contact author: Roger D. Carlini), “First determination of the weak charge of the proton”, Physical Review Letters (expected publication date: Oct 2)
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Finding New Superconductors
Theoretical calculations have lead to the successful design of a new iron-based superconductor.
Designing new materials that exhibit complex properties, such as superconductivity, is a notoriously challenging task, but computational and theoretical advances in solid-state physics are beginning to change this trend. A team of researchers from Europe and the US, guided by the conclusions of a previous theoretical study, was able to synthesize a superconducting iron-based compound. Their characterization showed the material behaved as calculations predicted: it exhibits low-temperature superconductivity, combined with an unusual hardness that may be advantageous for applications. The result provides an encouraging step in the quest for materials by design.
* Huiyang Gou, Natalia Dubrovinskaia (contact author) et al, “Discovery of a superhard iron tetraboride superconductor”, Physical Review Letters (expected publication date: Oct 7)
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Trapping Atoms in Magnetic Vortices
In optical lattices, ultracold atoms are trapped by lasers in periodic arrangements that can be used to simulate the physics of crystals. But atoms cannot be trapped too closely, as the separation is limited by the wavelength of light. According to a new proposal by a research group at the Max Planck Institute for Quantum Optics in Germany, atoms could be trapped by magnetic, rather than optical, means, using the magnetic vortices that can be generated in a thin superconducting sheet. The scheme could trap atoms at distances as small as few tens of nanometers, allowing the study of conditions in which mutual interactions are much stronger than in conventional optical lattices.
* Oriol Romero-Isart (contact author) et al, “Superconducting Vortex Lattices for Ultracold Atoms”, Physical Review Letters (expected publication date: Oct 4)
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Journal articles and preprints are available to journalists on request.
Matteo Rini, PhD
Deputy Editor, Physics
Tuesday, September 24, 2013
APS Physics Tip Sheet – Sep 23, 2013
In this issue: Is it Quantum Computing?, Matter Adds Twist to Cosmic Microwave Background, Planetary Waves that Connect the Climate Network, Accelerating Electrons with Light
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Is it Quantum Computing?
Scientists at D-Wave, the Canadian company that claims to have built the first commercial quantum computer, report they have used their hardware to solve a famously difficult problem in mathematics.
The heart of the device used by the D-Wave team is an array of 84 tiny superconducting loops, each representing one bit in the form of a current that can flow clockwise, counterclockwise, or in a quantum “superposition” of the two states. As a proof of principle, the researchers ran an algorithm on their hardware to solve the Ramsey problem - an optimization challenge similar in flavor to the traveling salesman problem (finding the optimal route that connects a number of cities) - for a few simple cases where the solutions were already known. A Viewpoint commentary appearing in Physics September 25provides a critical analysis of the report and explains what further experiments are needed to be sure the researchers have performed a truly “quantum” computation that could outperform what classical hardware can do.
* Z Bian, Frank Gaitan (contact author) et al, “Experimental determination of Ramsey numbers”, Physical Review Letters (expected publication date: Sep 25)
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Matter Adds Twist to Cosmic Microwave Background
A microwave telescope at the South Pole has captured a signal in the cosmic microwave background that arises from gravitational lensing by intervening matter.
The cosmic microwave background (CMB) provides us with a snapshot of the early Universe of 13.7 billion years ago. But this ancient photography has been slightly distorted: as CMB light rays propagated through the Universe, the matter they encountered on their path deflected them through the effect called “gravitational lensing”. Some aspects of this lensing have been observed before, but now a team of researchers at the South Pole Telescope (SPT) has detected for the first time a subtle twisting in the polarization of the CMB due to gravitational lensing. Collecting these signals could help scientists map the distribution of matter in the Universe, including the invisible dark matter, and may be used to detect primordial gravitational waves.
* The SPTpol Collaboration (contact author: Duncan Hanson), “Detection of B-mode polarization in the cosmic microwave background with data from the South Pole Telescope”, Physical Review Letters (expected publication date: Sep 30)
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Planetary Waves that Connect the Climate Network
(Image credit: NASA/GSFC)
A new study suggests that giant, high-altitude air waves have a profound effect on how energy is transported within the climate system.
Rossby waves are planetary-scale meanders in the high-altitude winds that flow about 10 km above ground. They arise because of the temperature difference between polar air and tropical air, together with variation of the Coriolis force with latitude. Meteorologists know them well, as they determine low-pressure systems that have a major influence on the weather. But according to simulations by a research team in Israel, such waves may determine more than whether it will rain or shine in the short term: they redistribute energy on planetary scales, connecting remote regions and thereby affecting the longer-term dynamics of the climate system. The finding may help improve the accuracy of global climate models.
* Yang Wang (contact author) et al, “Dominant imprint of Rossby waves in the climate network”, Physical Review Letters (published Sep 24)
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Accelerating Electrons with Light
Researchers at the Max Planck Institute of Quantum Optics have demonstrated that, in the vicinity of finely patterned substrates, laser pulses can accelerate electrons more efficiently than large-scale accelerator facilities. The principle may lead to compact, laboratory-size accelerators or to versatile light and x-ray sources.
* J Breuer, Peter Hommelhoff (contact author), “Laser-based acceleration of nonrelativistic electrons at a dielectric structure”, Physical Review Letters (expected publication date: Sep 27)
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Journal articles and preprints are available to journalists on request.
Matteo Rini, PhD
Deputy Editor, Physics
Tuesday, September 17, 2013
APS Physics Tip Sheet – Sep 17, 2013
In this issue: Foiling Quantum Hackers, Are Neutrinos Their Own Antiparticles?, Friction at the Atomic Scale
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Foiling Quantum Hackers
Researchers have implemented a new quantum encryption method that may provide the ultimate security against hackers in real-world cryptography applications.
Quantum cryptography holds promise for communication schemes that are, in theory, perfectly secure because they are protected by the fundamental laws of quantum mechanics: an eavesdropper cannot measure photons without disturbing their delicate quantum properties – and being noticed in the process. But in the last few years, hackers have exploited security loopholes to crack some of the most sophisticated quantum encryption systems. Now, two independent teams of researchers (the first based in China, the second in Canada) have implemented a new quantum encryption method that removes the most problematic link of quantum encryption schemes: weaknesses of the detectors used at the receiver end.
* Y Liu, Qiang Zhang (contact author) et al, “Experimental measurement-device-independent quantum key distribution”, Physical Review Letters
** A Rubenok, Joshua A Slater (contact author) et al, “Real-world two-photon interference and proof-of-principle quantum key distribution immune to detector attacks”, Physical Review Letters
(expected publication date: Sep 23)
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Are Neutrinos Their Own Antiparticles?
A new study disproves the results of a 2004 experiment that claimed to show the neutrino and the antineutrino are the same particle.
In the 1930s, the physicist Ettore Majorana suggested neutrinos might be their own antiparticle. The idea is in conflict with the standard model of particle physics, but might help explain certain properties of neutrinos, such as their small mass. If the hypothesis is true, neutrinos may annihilate with each other and disappear in a rare nuclear reaction known as “double beta decay”, in which two neutrons decay into a pair of protons. In experiments carried out in 2004, physicists argued they had seen signs of such neutrino-less decays, but now the GERDA collaboration at the Gran Sasso National Laboratory in Italy has conclusively refuted the earlier results. The researchers built a device with unprecedented sensitivity to the rare decay, showing that the rate of neutrino-less double beta decay—if it occurs at all—is less than a part in ten thousand of that of normal double beta decay.
* The GERDA collaboration (contact author: Peter Grabmayr), “Results on neutrinoless double-β decay of 76-Ge from phase I of the GERDA experiment”, Physical Review Letters (expected publication date:Sep 19)
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Friction at the Atomic Scale
Researchers from Germany and the Czech Republic have demonstrated a new experimental method based on atomic force microscopy (AFM) that allows the investigation of friction at the scale of individual atoms.
* Jay Weymouth (contact author) et al, “Atomic structure affects the directional dependence of friction”, Physical Review Letters (expected publication date: Sep 18)
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Journal articles and preprints are available to journalists on request.
Matteo Rini, PhD
Deputy Editor, Physics
Thursday, May 23, 2013
Gaming the uncertainty principle: more precision from less predictability
LY13750 - 
Contrary to what the Heisenberg uncertainty relation might naively suggest, particle properties such as position and momentum can be simultaneously measured in some circumstances – and with high precision. We show this experimentally for the case of photon polarization properties. We also verify that while the product of the measurement precisions can be arbitrarily small, these precisions are nevertheless constrained to obey a new generalization of the Heisenberg uncertainty relation.
Quantum mechanics is often thought to imply that you can precisely estimate how fast an electron is moving, or exactly where it is, but not both at the same time. The argument is that properties such as speed and position require physically incompatible devices for their precise measurement. Hence, any device used to make a simultaneous measurement will give inherently imprecise estimates.
This argument was challenged by Einstein in 1935, who gave an example where the position and speed could be accurately measured at the same time, by exploiting quantum correlations with a second particle. Note this is not in direct conflict with the well-known Heisenberg uncertainty relation, which only requires that the position and momentum cannot both be accurately predicted beforehand. However, it leaves open the important question of whether any quantum restrictions apply to simultaneous measurements.
We have experimentally verified that Einstein was correct, using polarisation properties of photons rather than position and momentum. But we also show that a high degree of joint precision does not come for free – it is only possible if the measurement outcomes are sufficiently unpredictable, as quantified by a suitable generalisation of the Heisenberg uncertainty relation.
Contrary to what the Heisenberg uncertainty relation might naively suggest, particle properties such as position and momentum can be simultaneously measured in some circumstances – and with high precision. We show this experimentally for the case of photon polarization properties. We also verify that while the product of the measurement precisions can be arbitrarily small, these precisions are nevertheless constrained to obey a new generalization of the Heisenberg uncertainty relation.Quantum mechanics is often thought to imply that you can precisely estimate how fast an electron is moving, or exactly where it is, but not both at the same time. The argument is that properties such as speed and position require physically incompatible devices for their precise measurement. Hence, any device used to make a simultaneous measurement will give inherently imprecise estimates.
This argument was challenged by Einstein in 1935, who gave an example where the position and speed could be accurately measured at the same time, by exploiting quantum correlations with a second particle. Note this is not in direct conflict with the well-known Heisenberg uncertainty relation, which only requires that the position and momentum cannot both be accurately predicted beforehand. However, it leaves open the important question of whether any quantum restrictions apply to simultaneous measurements.
We have experimentally verified that Einstein was correct, using polarisation properties of photons rather than position and momentum. But we also show that a high degree of joint precision does not come for free – it is only possible if the measurement outcomes are sufficiently unpredictable, as quantified by a suitable generalisation of the Heisenberg uncertainty relation.
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