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News Picks

Physics Today’s online staff summarize the most important and interesting news about science from the world's top media outlets.

There are 71 posts for the selected month (October 2014).

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October 24, 2014 1:04 PM

EU commits to stringent reductions in carbon emissions

BBC: At a meeting yesterday in Brussels, the leaders of the countries that constitute the European Union committed themselves to reducing the EU's total emissions of carbon dioxide by 2030 to levels that are 40% lower than they were in 1990. Although the target is ambitious, it represents a compromise between environmental groups, which had pushed for greater reductions, and the leaders of the countries, such as Poland, that obtain a large fraction of their electrical energy from coal-fired plants. The EU is already on course to cut its CO2 emissions by 20% by 2020 compared with 1990 levels.

October 24, 2014 1:03 PM

Algorithm runs faster on quantum computer

New Scientist: Twenty years ago Daniel Simon devised a simple period-finding problem that a quantum computer could conceivably solve exponentially faster than a classical computer. Now Mark Tame of the University of KwaZulu-Natal in Durban, South Africa, and his collaborators have built an elementary, photon-based quantum computer that not only solves Simon's problem but also reaches a solution faster when run in quantum mode than in classical mode. Although Simon's problem is too simple to be useful, its design inspired other, potentially more useful algorithms.

October 24, 2014 1:02 PM

Archival data constrain properties of hypothetical dark-matter particles

Science: An experiment that ran at SLAC from 1980 to 1982 shot a beam of electrons at an aluminum target in hope of detecting evidence of axions, hypothetical particles devised to explain the absence of CP violation in the strong nuclear force. No axions were seen, and the negative result was duly written up. Decades later Rouven Essig of Stony Brook University in New York realized that the old experiment, known as E137, could also shed light on another hypothetical particle, the dark-matter candidate known as the χ. If χ particles behave as originally conceived, they would have caused a signal in E137 that the experimenters would have seen, but didn't. Essig and his collaborators' reinterpretation of the old experiment doesn't rule out χ particles, but it does constrain their properties.

October 24, 2014 1:01 PM

Aleutian tsunami likely swamped Hawaii centuries ago

Ars Technica: Tsunamis occur when an earthquake causes a section of an undersea fault to slip. The sudden displacement of crust launches a wave perpendicular to the fault. Knowing the positions of the faults that encircle the Pacific Ocean, Rhett Butler of the University of Hawaii at Manoa and his colleagues modeled the propagation of tsunamis from the northern Pacific. Their goal: to determine the origin of a huge tsunami that deposited debris in a sinkhole on the Hawaiian island of Kauai centuries ago. To fill the sinkhole, which lies 100 m from the shore, the tsunami must have topped 7 m. According to the simulations that Butler and his colleagues performed, the earthquake that caused the tsunami must have had a magnitude of at least 9. Crucially, the earthquake must have originated in the eastern Aleutian Islands. Tsunamis launched from other locations miss Hawaii.

October 23, 2014 2:51 PM

Study compares true economic costs of power sources

MIT Technology Review: The European Union commissioned Ecofys, a sustainable energy consultancy, to prepare an economic cost evaluation of different energy sources in the EU. Instead of using standard metrics, the company considered "true economic costs." Those include the cost of the source's contribution to climate change, pollution, and resource depletion and the costs of creating and operating the plants and related technologies. They also excluded the effect of subsidies, which decrease the apparent cost of relevant energies. The study revealed that while traditional fossil fuels are significantly more expensive than alternative energy sources, solar energy is notably more expensive than wind or hydroelectric. The primary cause for the difference is that most solar panels are built in China, where electricity is carbon-intensive and pollution is a significant problem. Solar panels also contribute more significantly to the depletion of resources than wind and hydroelectric plants.

October 23, 2014 1:24 PM

Archival research papers are increasingly free to read

Nature: A study commissioned by the European Union's executive branch has determined that 54% of all research papers published worldwide between 2007 and 2012 are freely accessible online. The fraction has been steadily increasing. In 1996, the start of the study period, only 28% of papers were free to read. The upward trend reflects the growing use of embargoes that liberate papers from access controls after a year or more. Also contributing to the trend is researchers' practice of posting freely accessible copies of their papers on their websites. Although the fraction of papers published in open-access journals continues to increase, those papers amounted to only 13% of the freely accessible total in 2012.

October 23, 2014 11:14 AM

Some superbright x-ray sources may be unusual pulsars

Ars Technica: Since their discovery in the 1970s, ultraluminous x-ray sources (ULXs) continue to puzzle astronomers. At first they were thought to be stellar-sized black holes, but their luminosity exceeded a theoretical limit based on their masses. Recent observations have suggested that they are intermediate-sized black holes, with masses on the order of 100 to 100 000 times that of the Sun. But an unexpected finding about a known ULX in the M82 galaxy may complicate that possibility. Deepto Chakrabarty of MIT and his colleagues were using NASA's Nuclear Spectroscopic Telescope Array to watch the galaxy for a new supernova when they noticed that the brightness of ULX X-2 was pulsing, something that black holes don't do. Using the Chandra X-Ray Telescope, the researchers confirmed that it was in fact X-2 that was pulsing. That makes it possible that X-2 and other ULXs are pulsars—bright, rapidly rotating neutron stars—and not black holes. However, X-2 is significantly brighter than any other known pulsars. The same limit to black hole luminosity applies to pulsars, and X-2 exceeded the limit by a factor of 100. Chakrabarty recalculated X-2's mass using the version of the brightness limit that accounts for a pulsar's magnetic field and found that while the ULX's mass had increased, it was still two to three times brighter than it should be. To further confuse the situation, X-2 has a sibling, ULX X-1, that shows no sign of being a pulsar.

October 22, 2014 2:26 PM

Blood–brain barrier breached to treat cancer

New Scientist: Thanks to the close packing of the cells that line the blood vessels in our brains, only the smallest molecules can pass from the circulatory system into the central nervous system. Bacteria and viruses are too large to pass through the blood–brain barrier (BBB), but so too are antibiotics and drugs that treat cancer. Six years ago researchers from Harvard University and the University of Toronto used ultrasound to breach the BBB in lab rabbits by inducing microbubbles in the blood to vibrate and push apart the barrier's cells. Now a team from a Paris-based medical startup called CarThera has demonstrated a way of implementing that approach in human subjects. Rather than direct the ultrasound through the skull, as was done in the case of the rabbits, the researchers surgically implant an ultrasound transducer. The four patients in the ongoing trial all suffer from recurrent gliobastoma. After their tumors had been surgically removed, the transducers were installed through the same hole in the skull. Once a month the transducers are switched on while the patients receive normal chemotherapy. The success of the therapy in preventing the cancer's recurrence is likely to be known in a few months' time.

October 22, 2014 1:43 PM

Fish-scale shininess shares the same structural origin as beetles' bodies

BBC: Disordered layers of nanoscopic crystals in the iridescent wings and carapaces of various insects are known to cause the glittery shininess of those animals. Now the same phenomenon has been shown to be responsible for the silvery nature of fish scales. Nicholas Roberts of the University of Bristol in the UK and his colleagues have demonstrated that fish scales have a similar crystalline structure as other iridescent surfaces. As light enters the material, it bounces off different structural layers and reflects back with varying levels of interference and wavelength absorption, resulting in brilliant colors and luster. Adapting the structure could allow for the creation of highly reflective surfaces for use in lighting systems and other technologies.

October 22, 2014 1:22 PM

Archiving molecular structures challenges databases

Nature: Since its inception in 1971, the Protein Data Bank (PDB) has served as a freely accessible depository and archive for the three-dimensional structures of proteins and other biomolecules. Most of the structures in the PDB are for single molecules determined by x-ray crystallography. Now new techniques—and new combinations of techniques—record the structures of bulky molecular complexes, such as the ribosome. Some structures consist of movies. Earlier this month a workshop convened in Hinxton in the UK to tackle the challenge of storing those structures. Not only do they require more disk space, they also require new formats to define them. As Ewen Callaway reports for Nature, the workshop resolved to seek funding to meet those challenges and to set up a new database dedicated to the ribosome, RNA polymerase, and other molecular machines.

October 22, 2014 12:06 PM

Lockheed Martin looking for compact fusion reactor partners

Science: Lockheed Martin recently received a lot of publicity for revealing a project to create a compact fusion reactor. At a press conference yesterday, Tom McGuire, the project leader, said the goal of going public was to help find R&D partners. The company has been working on the project for the past four years and believes it has a viable design that combines aspects of several past fusion projects. The core of the reactor uses multiple layers of magnetic confinement and recirculates particles through the system. McGuire said the test device that the team built sustained a stable plasma on more than 200 runs, but he did not provide any details about the measurements. The team hopes to have enough information to publish sometime next year.

October 21, 2014 2:00 PM

Italian scientists appeal conviction concerning 2009 earthquake

Nature: An appeal is in progress for the six Italian seismologists and one government official who were implicated in the deaths of 29 people during the 2009 L’Aquila earthquake. In 2012 the seven were convicted of failing in their duty to evaluate and communicate the risk of a large earthquake to the general public. Sentenced to six years in prison and permanently banned from public service, the men maintain their innocence. They deny having made any reassuring statements, point out that their meeting to discuss the issue had been private, and instead blame the media for the subsequent misunderstanding. The prosecution maintains that the accused did not sufficiently highlight the probability of a strong earthquake and did nothing to contradict what was reported. The appeal, which began 10 October, is expected to be concluded by early November.

October 21, 2014 1:53 PM

Optical tractor beam pushes and pulls objects at greatest distance yet

Guardian: A hollow laser has been developed that performs like a tractor beam to push and pull objects over relatively large distances. The objects it moves are only 0.2 mm in diameter, but it can move them up to 20 cm—more than 100 times as far as any previous tractor beam. Created by Wieslaw Krolikowski of the Australian National University and his colleagues, the hollow laser acts like a tube and surrounds the object, and the light heats the object's surface. When air particles hit the heated areas, they are accelerated away, which causes the object to move in the opposite direction. The researchers believe that the effect could be extended over distances of meters, but their lab was not large enough to test the theory.

October 21, 2014 12:15 PM

Possible El Niño builds off the coast of Australia

Sydney Morning Herald: Weather bureaus around the world are keeping a close eye on conditions in the tropical Pacific Ocean, where it looks like an El Niño event may be imminent. Sea-surface temperatures around Australia have been warming since March, and the last two weeks have seen a marked rise. In addition, the continent has been experiencing warmer and drier conditions than usual. All are signs of an impending El Niño, and the US National Oceanic and Atmospheric Administration predicts one will begin in the next one to two months. El Niño events in the Pacific have global repercussions, and combined with global warming in general, even a weak El Niño this year could make 2014 the hottest year since record keeping began in 1880.

October 21, 2014 11:46 AM

Power companies seek to extend life of nuclear reactors to 80 years

New York Times: Getting permission to build new nuclear reactors is difficult, and building them is extremely expensive. To help fill the gap before new reactors are operational, power companies have sought and been granted extensions for their existing reactors. Most were originally built in the 1980s, with a predicted economic lifespan of 40 years. To date, more than 70 reactors have been granted 20-year extended licenses by the Nuclear Regulatory Commission. Now, three power companies are requesting extensions of yet another 20 years for some of their reactors. Although concerns have been expressed about the possible long-term effects of radiation on the metal and concrete in the reactors and their cooling systems, both NRC staff and industry experts agree that with proper monitoring, the extended operations should be safe. The question now is what that proper monitoring would entail.

October 20, 2014 4:00 PM

US–Iran nuclear deal may bypass Congress

New York Times: As the US negotiates with Iran over its nuclear program, President Obama may end up striking a temporary deal without the approval of Congress. According to the Treasury Department, the president has the authority to suspend many of the US sanctions against Iran without waiting for a congressional vote. However, such a suspension would only be temporary, as only Congress has the power to permanently terminate them. The sanctions have proven to be a valuable bargaining point with Iran. Hence proponents emphasize that lifting any sanctions must be a gradual process, with Iran allowing the International Atomic Energy Agency to verify step by step that the necessary benchmarks have been met. It is hoped that some agreement can be reached so that Iran does not revert to covert means of obtaining nuclear technology.

October 20, 2014 2:40 PM

Graphene-like material has piezoelectric properties

Ars Technica: Piezoelectric materials develop an electric field when they are stretched or compressed. Practical piezoelectrics tend to be bulk crystals or crystalline thin films, but piezoelectricity has been predicted in crystals just one atom thick. Now, molybdenum disulfide (MoS2), which is not piezoelectric in bulk, has been shown to be piezoelectric under certain interesting conditions. The material is strongly piezoelectric when it is just one atom thick, but the effect is eliminated when a second layer is added. With a third layer, it is piezoelectric again, but less so than before. Experimentation revealed that the material is piezoelectric only when there is an odd number of layers, and that its strength decreases as the number of layers increases. Computational modeling suggests that the layers have random orientations, causing them to cancel each other out. Further testing also showed that the more single-layer flakes that are arranged in series, the higher the produced voltage. That means that MoS2 could potentially be used for powering nanoelectronics and wearable technologies.

October 20, 2014 11:25 AM

Unusual x-ray signal could be sign of axions, a potential form of dark matter

Nature: Axions are hypothetical, uncharged, extremely light particles that were originally proposed to explain the absence of CP violation in the strong nuclear force. The particles were later adopted by theorists as a potential form of dark matter, and now, they may have been detected. George Fraser of the University of Leicester, UK, and his colleagues analyzed 12 years of x-ray data collected by the European Space Agency’s X-Ray Multi Mirror Mission (XMM-Newton) as it orbited Earth. They found an unexplained surplus of x rays as the satellite passed between Earth and the Sun. After ruling out all known possible causes, Fraser’s team proposes that the surplus could be caused by axions from the Sun being transformed into x-ray photons by Earth’s magnetic field. They have also found tentative evidence of the same signal in data from the Chandra X-Ray Observatory, but several more years of data are needed to confirm the signal. Even if the signal holds up, the cause could lie in the physics of the Sun's x-ray emitting corona rather than in the transformation of axions into x rays.

October 20, 2014 10:20 AM

Tunisian sunshine may one day power homes in the UK

BBC: A large-scale solar export project is in the works that would transport energy from Tunisia to the UK. The TuNur project, a partnership between a group of Tunisian investors and UK-based Nur Energie, would consist of concentrated solar power plants located in the Tunisian desert and a 2-GW high-voltage direct-current cable to transport the energy to Italy. From there it could be sold to customers in the UK and, perhaps, various other European countries. The developers claim the electricity supplies will be secure, deliverable on demand, and cheaper than home-based sources, such as offshore wind. The project is one of several being proposed by renewable energy developers that are based outside the UK.

October 17, 2014 2:50 PM

Seven Chinese scientists charged with corruption

Nature: The Chinese government has charged seven leading scientists with misusing millions of dollars in government research grants. The charges are based on an investigation by the National Audit Office (NAO) of more than a dozen large engineering and applied research projects, which together receive $8 billion a year in funding. Among the allegations are the appropriation of research funds for personal use and the forging of receipts and invoices. And the problem may be even more widespread. According to a report released by the NAO last year, it's possible that up to half of all research funds have been misused. At least one science policy expert says that it points up the lack of guidelines and oversight mechanisms concerning the allocation of research grants in China.

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