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Updated: 2 weeks 6 days ago

Language used in UK research case studies reveals how words affect assessment scores

12 February 2015

Nature: Every few years the Higher Education Funding Council for England assesses the value of the research performed by the UK’s universities. The 2014 audit required that universities explain the impact of their research efforts through case studies that would account for 20% of their grade; the council received nearly 7000 of them. At the request of Nature, Paul Ginsparg of Cornell University performed a statistical analysis of the words used and found some predictable results, such as the frequent use of "research" and "impact." Other words used often were "development," "policy," and "health." Ginsparg noted a correlation between high assessment scores and the frequent use of words such as "million," "market," "government," "major," and "global." He also found a similar correlation between low scores and the repeated use of words such as "conference," "university," "academic," and "project." That could suggest that language used to show the research’s economic impact was more appealing to the graders.

New reactor design could make nuclear power cheaper, safer

12 February 2015
MIT Technology Review: A startup company, Transatomic Power, is developing a nuclear reactor that instead of using water as a coolant will use a new type of molten salt that will allow the reactor to burn its nuclear waste. Because the molten salt evaporates at a much higher temperature than water, it should also continue to cool the reactor even if the pumps fail, as happened at Fukushima in 2011. Additionally, the reactor will use zirconium hydride rather than graphite to keep the reactions going, since zirconium hydride is more resistant to radiation damage. The company says the reactor, which is based on a design developed at Oak Ridge National Laboratory in the 1960s, will be more compact and cheaper to build than current models. Transatomic is currently testing the design and hopes to have a demonstration model built by 2020.

Images reveal the formation of a multistar system

12 February 2015

Ars Technica: Many of the stars in the Milky Way coexist in binary, trinary, or larger systems. Despite the number of such systems, not much is known about their formation. New images of a star-forming area in the Perseus region have revealed the presence of a 0.1-solar-mass protostar surrounded by three other clusters of material, referred to as condensations, that are all likely to become protostars in the next 40 000 years. The condensations are connected to each other and to the protostar by filaments of gas that stretch across distances of up to 10 000 AU. Observations of the system revealed that the protostar and the condensations were barely moving relative to each other, which indicates that the regions are all gravitationally bound to each other. Whether the arrangement will actually evolve into a four-star system is not clear, but its existence supports the theory that gravitationally entangled stars can form from the same cloud of gas, rather than forming separately and only becoming entangled when they cross paths.

Carbon released from deep ocean led to end of Ice Age

12 February 2015
BBC: By studying the calcium carbonate shells left by marine organisms that lived thousands of years ago, researchers have been able to determine the acidity of the world’s oceans and, in turn, how much carbon dioxide they contained. They found that near the end of the last Ice Age, a reservoir of CO2 deep in the Southern Ocean was released into the atmosphere, which caused global temperatures to rise. Because Earth’s oceans currently absorb about 30% of anthropogenic fossil-fuel emissions, researchers say it’s important to understand the oceans’ role in the carbon cycle and how global warming could affect their ability to act as carbon sinks.

Predicting pentagonal graphene

12 February 2015
Calculations indicate that the carbon sheets are semiconducting and fairly robust.

High-speed cameras reveal secrets of popcorn's pop

11 February 2015

The Guardian: Researchers led by Emmanuel Virot of CNRS in Paris believe that they have an explanation for the popping sounds of popcorn. They combined high-speed cameras and audio recordings of popping kernels to show that the pop is not from the cracking of the kernel shells. Instead, the shape of the kernel serves as an acoustic resonator and causes the release of pressurized vapors to create the audible pop. A similar effect causes the pop of champagne corks. The team also found that the kernels pop when the vapor reaches 180 °C and that the "jump" of the pop occurs when starch in the kernel expands into the fluffy leaves that give popped corn its appearance.

European Space Agency launches mini-spaceplane

11 February 2015

BBC: Earlier today, the European Space Agency (ESA) launched the Intermediate Experimental Vehicle (IXV) atop a Vega rocket from French Guiana. The IXV will reach an altitude of 450 km before descending. The primary mission is a test of re-entry control systems on the wedge-shaped vehicle. The ESA has limited experience with returning vehicles to Earth and hopes to incorporate the knowledge gained from the launch into future craft.

Current geoengineering schemes likely ineffective

11 February 2015

Nature: A report by the US National Research Council (NRC) says that none of the plans put forward to reduce atmospheric carbon dioxide through geoengineering are likely to be effective. The report provides an official stance for the government regarding a field that the NRC calls "climate intervention" because other names imply a level of knowledge and ability that does not exist. Several proposed plans to change the atmosphere's reflectivity to directly alter Earth's climate were rejected as too risky; information about the full effects of such plans is lacking. In contrast, plans for carbon capture and storage were considered not particularly risky. However, the report considers the technology to be too new, expensive, inefficient, and damaging to the environment in other ways to be truly effective at reducing CO2 levels significantly in the near term.

Australian government signals push for national focus on science

11 February 2015

Sydney Morning Herald: Karen Andrews, parliamentary secretary to the minister for industry and science, has called for a national focus on STEM education. She said the government would be considering a range of proposals in the quest to establish a national strategy for advancing scientific innovation. Australia's current economy is heavily dependent on mining and industries that will likely shrink significantly in the next 40 years. Andrews says a shift to a science- and technology-oriented economy could strengthen the country going forward.

Comsol application builder and application server: A review

11 February 2015
A powerful numerical analysis tool now comes with the ability to create apps.

The changing political climate for US science

10 February 2015
Disunity and dysfunction in Washington should not dissuade physicists from making the case for robust federal funding of science.

Andean ice core reveals air pollution before Industrial Revolution

10 February 2015

Science: The Quelccaya Ice Cap in Peru serves as a record of the tropical region's wet and dry seasons, which can be easily traced in the alternating layers of clean and dusty snow compacted in the glacier. A study of ice cores by Paolo Gabrielli of the Ohio State University and his colleagues has also revealed details about air pollution in the region over time. Around 1400 CE, the Incas began mining and smelting silver, which released lead and other materials into the atmosphere. Gabrielli's team found that, between 1450 and 1900, levels of lead in the ice cores doubled  and concentrations of antimony increased 3.5 times. The researchers believe the largest contributor was the Potosí silver mine operated by the Spanish, who came to South America in the 16th century. Air pollution decreased slightly during the 1800s, perhaps due to the South American wars of independence and the economic downturns that accompanied them. However, pollution levels increased drastically between 1900 and 1989 as mining expanded to copper and molybdenum and the number of automobiles multiplied. In that period, silver levels in the ice cores tripled, copper and lead levels doubled, and molybdenum levels increased more than twofold.

Smart insulin automatically controls glucose levels

10 February 2015
Guardian: Diabetes patients wrestle daily with monitoring their blood sugar levels and determining when to inject insulin and how much. Now researchers have developed an insulin derivative that binds to a protein in blood and automatically activates when blood sugar levels reach a certain threshold. Injected into diabetic mice just once a day, the glucose-responsive insulin kept their blood sugar levels as stable as those in healthy mice. The researchers hope to test the new compound, called Ins-PBA-F, in human patients within two to five years.

Toronto newspaper found guilty of libeling climate scientist

10 February 2015

Ars Technica: In Canadian law, libel is defined as the publication of statements that are factually inaccurate and that damage "the plaintiff's reputation in the eyes of a reasonable person." A Canadian court has held that several pieces published by Toronto's National Post libeled climate scientist Andrew Weaver. The judge found that the paper misrepresented Weaver's statements and activities regarding climate change. As punishment, the Post will have to remove all the offending posts from its website and pay a fine of C$50 000 ($39 500). The paper avoided further penalty by removing the libelous reader comments.

Earth's center may be more complex than thought

10 February 2015
BBC: Earth’s inner core may have its own core, according to a new study published in Nature Geoscience. Xiaodong Song of the University of Illinois at Urbana-Champaign and colleagues used the seismic waves generated by earthquakes to look deep into Earth’s center. They found that the inner core, a Moon-sized sphere located some 5000 km below the surface, appears to have two distinct regions. They made that determination based on the orientation of iron crystals in relation to the polar axis: The crystals in the inner inner core are oriented east–west, while those in the outer inner core are oriented north–south. According to the researchers, that difference in alignment suggests something happened in Earth’s past to cause the inner core to rotate.

Quantum and classical processes combine to solve mazes

9 February 2015

MIT Technology Review: In cells, energy is rapidly transported through large, complex protein matrices with almost no energy loss. Filippo Caruso of the University of Florence in Italy and his colleagues have shown that the mechanism involved in energy transfer across these maze-like proteins likely combines quantum and classical effects. By themselves, both quantum and classical solutions to finding paths through mazes suffer from loss of energy. Caruso's team combined the simultaneous evaluation of multiple paths of the quantum process with the random jumps of the classical. The resulting hybrid process outperformed both individual ones. The researchers created various mazes from waveguides spaced at different distances from each other. When the waveguides were close together, light took full advantage of quantum effects; when further apart, classical noise disrupted the system. Thus the researchers were able to measure for the best mixing of quantum and classical properties. Their system still doesn't compare with the efficiency of the energy transfer in proteins, but it does provide some potential insight into the process.

Forest fires rerelease radiation from Chernobyl disaster

9 February 2015
New Scientist: Smoke from forest fires in Ukraine and Belarus has been spreading radioactive contaminants left over from the Chernobyl nuclear disaster. Following the reactor explosion in 1986, the surrounding area was evacuated and dense forest has since grown up. Radioactive cesium and other elements that settled in the soil are now being released into the air via smoke from the fires. According to a study by Nikolaos Evangeliou of the Norwegian Institute for Air Research and colleagues, global warming is exacerbating the problem. Increasing droughts are causing the number and intensity of the fires to increase. In addition, the radiation appears to be slowing the decomposition of the leaves littering the forest floor, which only serves to further fuel the fires. The lack of forest maintenance—for example, removal of dead trees and the clearing of roads—and the dearth of firefighting equipment and personnel are worsening the situation. The study’s findings could also be important for other areas that have suffered a nuclear disaster, such as Fukushima, Japan.

Brookhaven's new synchrotron is turned on

9 February 2015

Science: Last week US Secretary of Energy Ernest Moniz officially dedicated the $912 million successor to Brookhaven National Laboratory's National Synchrotron Light Source. Known as NSLS-II, the new facility will use a variety of wavelengths of light to study materials at a resolution nearing 10 nm and will reach intensities 10 000 times brighter than its predecessor. Currently only 7 of the 70 planned beamlines are operational; 25 more will be added over the next five years.

Val Logsdon Fitch

9 February 2015

Op-ed sees 2015 as possibly "the year we confirm both the virtues and the limits of general relativity"

6 February 2015
In the International New York Times, Philip Ball tells the world about coming tests of "probably the most beautiful of all existing theories."