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Archive for the ‘particle physics’ category: Page 176

Apr 17, 2019

Researchers explore energy-saving catalysts that operate at room temperature

Posted by in categories: nanotechnology, particle physics

NIST researchers have explored in unprecedented detail a new breed of catalysts that allow some chemical reactions, which normally require high heat, to proceed at room temperature. The energy-saving catalysts use sunlight or another light source to excite localized surface plasmons (LSPs)—oscillations of groups of electrons on the surface of certain metal nanoparticles, such as gold, silver and aluminum. The energy derived from the LSP oscillations drives chemical reactions among molecules that adhere to the nanoparticles.

Scientists had previously shown that can be split into its individual atoms by the energy generated by the LSP oscillations. The NIST team has now discovered a second LSP-mediated reaction that proceeds at room temperature. In this reaction, LSPs excited in gold nanoparticles transform two molecules of carbon monoxide into carbon and carbon dioxide. The reaction, which ordinarily requires a minimum temperature of 400 degrees C., plays an important role in converting carbon monoxide into widely used carbon-based materials such as carbon nanotubes and graphite.

Probing the nanoparticles with an and combining the data with simulations, the NIST researchers pinpointed the sites on the gold nanoparticles where the reactions occurred. They also measured the intensity of the LSPs and mapped how the energy associated with the oscillations varied from place to place inside the nanoparticles. The measurements are key steps in understanding the role of LSPs for initiating reactions at room temperature, mitigating the need to heat the samples.

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Apr 16, 2019

Optimizing network software to advance scientific discovery

Posted by in categories: mathematics, particle physics, supercomputing

High-performance computing (HPC)—the use of supercomputers and parallel processing techniques to solve large computational problems—is of great use in the scientific community. For example, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory rely on HPC to analyze the data they collect at the large-scale experimental facilities on site and to model complex processes that would be too expensive or impossible to demonstrate experimentally.

Modern science applications, such as simulating , often require a combination of aggregated computing power, high-speed networks for data transfer, large amounts of memory, and high-capacity storage capabilities. Advances in HPC hardware and software are needed to meet these requirements. Computer and computational scientists and mathematicians in Brookhaven Lab’s Computational Science Initiative (CSI) are collaborating with physicists, biologists, and other domain scientists to understand their data analysis needs and provide solutions to accelerate the scientific discovery process.

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Apr 15, 2019

Astronomers take first, high-resolution look at huge star-forming region of Milky Way

Posted by in categories: particle physics, space

Astronomers from the United States and South Korea have made the first high-resolution, radio telescope observations of the molecular clouds within a massive star-forming region of the outer Milky Way.

“This region is behind a nearby cloud of dust and gas,” said Charles Kerton, an associate professor of physics and astronomy at Iowa State University and a member of the study team. “The cloud blocks the light and so we have to use infrared or radio observations to study it.”

The Milky Way region is called CTB 102. It’s about 14,000 light years from Earth. It’s classified as an HII region, meaning it contains clouds of ionized—charged—hydrogen atoms. And, because of its distance from Earth and the dust and gas in between, it has been difficult to study.

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Apr 12, 2019

This Electrically Conductive Concrete Melts Snow Without Chemicals

Posted by in categories: particle physics, transportation

A special blend of concrete that can de-ice roads and pavements without the need for chemicals uses electricity to melt away snow and sleet – and it could be coming to an airport near you soon.

The conductive concrete, developed by researchers at the University of Nebraska-Lincoln, is for the most part the same as regular concrete, but 20 percent of its ingredients aren’t exactly standard: steel shavings and carbon particles, which give the mix enough conductivity that it can melt ice and snow while remaining safe to the touch.

Designed by civil engineer Chris Tuan, the conductive concrete is currently being assessed by the US Federal Aviation Administration (FAA), which is looking into the possibilities of incorporating the snow-melting surface into the tarmac of at least one major airport as part of a trial.

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Apr 12, 2019

Fluc­tu­a­tions in the void

Posted by in categories: particle physics, quantum physics

In quantum physics, a vacuum is not empty, but rather steeped in tiny fluctuations of the electromagnetic field. Until recently it was impossible to study those vacuum fluctuations directly. Researchers at ETH Zurich have developed a method that allows them to characterize the fluctuations in detail.

Emptiness is not really empty – not according to the laws of , at any rate. The vacuum, in which classically there is supposed to be “nothing,” teems with so-called according to quantum mechanics. Those are small excursions of an electromagnetic field, for instance, that average out to zero over time but can deviate from it for a brief moment. Jérôme Faist, professor at the Institute for Quantum Electronics at ETH in Zurich, and his collaborators have now succeeded in characterizing those vacuum fluctuations directly for the first time.

“The vacuum fluctuations of the electromagnetic field have clearly visible consequences, and among other things, are responsible for the fact that an atom can spontaneously emit ,” explains Ileana-Cristina Benea-Chelmus, a recently graduated Ph.D. student in Faists laboratory and first author of the study recently published in the scientific journal Nature. “To measure them directly, however, seems impossible at first sight. Traditional detectors for light such as photodiodes are based on the principle that light particles – and hence energy – are absorbed by the detector. However, from the vacuum, which represents the lowest energy state of a physical system, no further energy can be extracted.”

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Apr 11, 2019

Team makes artificial atoms that work at room temp

Posted by in categories: computing, particle physics, quantum physics

Ultra-secure online communications, completely indecipherable if intercepted, is one step closer with the help of a recently published discovery by University of Oregon physicist Ben Alemán.

Alemán, a member of the UO’s Center for Optical, Molecular, and Quantum Science, has made artificial atoms that work in ambient conditions. The research, published in the journal Nano Letters, could be a big step in efforts to develop secure communication networks and all-optical quantum computing.

“The big breakthrough is that we’ve discovered a simple, scalable way to nanofabricate artificial atoms onto a microchip, and that the artificial atoms work in air and at ,” said Alemán, also a member of the UO’s Materials Science Institute.

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Apr 11, 2019

Infinite number of quantum particles gives clues to big-picture behavior at large scale

Posted by in categories: particle physics, quantum physics

In quantum mechanics, the Heisenberg uncertainty principle prevents an external observer from measuring both the position and speed (referred to as momentum) of a particle at the same time. They can only know with a high degree of certainty either one or the other—unlike what happens at large scales where both are known. To identify a given particle’s characteristics, physicists introduced the notion of quasi-distribution of position and momentum. This approach was an attempt to reconcile quantum-scale interpretation of what is happening in particles with the standard approach used to understand motion at normal scale, a field dubbed classical mechanics.

In a new study published in EPJ ST, Dr. J.S. Ben-Benjamin and colleagues from Texas A&M University, USA, reverse this approach; starting with quantum mechanical rules, they explore how to derive an infinite number of quasi-distributions, to emulate the approach. This approach is also applicable to a number of other variables found in quantum-scale particles, including particle spin.

For example, such quasi-distributions of position and momentum can be used to calculate the quantum version of the characteristics of a gas, referred to as the second virial coefficient, and extend it to derive an infinite number of these quasi-distributions, so as to check whether it matches the traditional expression of this physical entity as a joint distribution of position and momentum in classical mechanics.

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Apr 11, 2019

Building a Higgs boson factory: China’s race to the frontier of physics

Posted by in category: particle physics

While Wang’s team was the first in the world to unveil a detailed concept design for an LHC successor, there are three other competing proposals – one in Japan and two from CERN.


One team in Beijing is leading the charge to create the next generation of giant particle colliders to unlock the mysteries of the fundamental forces of the universe.

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Apr 10, 2019

New algorithm optimizes quantum computing problem-solving

Posted by in categories: business, computing, information science, particle physics, quantum physics

Tohoku University researchers have developed an algorithm that enhances the ability of a Canadian-designed quantum computer to more efficiently find the best solution for complicated problems, according to a study published in the journal Scientific Reports.

Quantum computing takes advantage of the ability of subatomic particles to exist in more than one state at the same time. It is expected to take modern-day computing to the next level by enabling the processing of more information in less time.

The D-Wave annealer, developed by a Canadian company that claims it sells the world’s first commercially available quantum computers, employs the concepts of quantum physics to solve ‘combinatorial optimization .’ A typical example of this sort of problem asks the question: “Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each and returns to the original city?” Businesses and industries face a large range of similarly complex problems in which they want to find the optimal solution among many possible ones using the least amount of resources.

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Apr 9, 2019

Scientists build a machine to generate quantum superposition of possible futures

Posted by in categories: computing, information science, particle physics, quantum physics

In the 2018 movie Avengers: Infinity War, a scene featured Dr. Strange looking into 14 million possible futures to search for a single timeline in which the heroes would be victorious. Perhaps he would have had an easier time with help from a quantum computer. A team of researchers from Nanyang Technological University, Singapore (NTU Singapore) and Griffith University in Australia have constructed a prototype quantum device that can generate all possible futures in a simultaneous quantum superposition.

“When we think about the future, we are confronted by a vast array of possibilities,” explains Assistant Professor Mile Gu of NTU Singapore, who led development of the algorithm that underpins the prototype “These possibilities grow exponentially as we go deeper into the future. For instance, even if we have only two possibilities to choose from each minute, in less than half an hour there are 14 million possible futures. In less than a day, the number exceeds the number of atoms in the universe.” What he and his research group realised, however, was that a quantum computer can examine all possible futures by placing them in a – similar to Schrödinger’s famous cat, which is simultaneously alive and dead.

To realise this scheme, they joined forces with the experimental group led by Professor Geoff Pryde at Griffith University. Together, the team implemented a specially devised photonic quantum information processor in which the potential future outcomes of a decision process are represented by the locations of photons – quantum of light. They then demonstrated that the state of the quantum device was a superposition of multiple potential futures, weighted by their probability of occurrence.

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