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Updated: 25 min 11 sec ago

US improves solar-storm predictions

21 September 2016
Nature: Because of the damage solar storms can inflict on electrical power grids, a new prediction model has been developed that pinpoints which areas on Earth will most likely be affected by a given storm. Until now, solar storms could be predicted with some confidence, but which regions would be affected could not. The US National Oceanic and Atmospheric Administration has upped its game by combining three models—one of Earth’s entire magnetosphere, one of its inner magnetosphere, and another for the upper atmosphere’s electrical activity—into a more sophisticated prediction system that draws data from a satellite located some 1.6 million km away. The new system can alert utility operators to impending storms about 20–60 minutes in advance.

Forensics techniques found not to be as accurate as thought

21 September 2016
Ars Technica: Because of problems with forensics practices raised in a 2009 report from the National Research Council, President Obama asked the President’s Council of Advisors on Science and Technology (PCAST) to investigate the validity of forensic evidence. Among the techniques examined were hair, DNA, fingerprint, firearm marking, footwear, and bite-mark analyses. According to the PCAST report, which has just been released, all those techniques have problems. The least reliable is bite-mark analysis because the technique cannot reliably establish the source of a bite or determine whether it was inflicted by a human. DNA analysis, although found to be scientifically sound, can be prone to human error in its application. PCAST recommends that most of the techniques be put on a more firm scientific foundation, that better proficiency testing be devised for practitioners, and that more objective identification methods be developed.

Solving Antarctic fossil mystery reinforces climate change concerns

21 September 2016
Washington Post: How fossilized marine diatoms ended up on top of a mountain range in Antarctica has long puzzled scientists. The fossils date from the Pliocene era, about 2 million to 5 million years ago. When the fossils were first discovered in 1984, two theories were proposed. The so-called dynamicists said that the melting of the East Antarctic Ice Sheet (EAIS) raised ocean levels and that isostatic uplift caused new landmasses to rise; the combination caused the diatoms to be transported from the seafloor to the mountaintops. The stabilists countered that the ice sheet did not change; instead, powerful winds blew the diatoms from the ocean into the mountains. According to a new study by Reed Scherer of Northern Illinois University and his colleagues, what actually happened was a combination of both: The EAIS did retreat, but not as far as previously thought, and winds carried the diatoms the rest of the way. Besides solving the diatom mystery, the study also points up the vulnerability of the EAIS to global warming and raises concerns as current atmospheric carbon levels approach those of the Pliocene.

Samuel Wilson Marshall

20 September 2016

Disappearing star might be first known failed supernova

20 September 2016

Science News: In 2009, a star 19 million light-years away increased in brightness over the span of several months, eventually reaching a luminosity 1 million times that of the Sun. The star appeared to be going supernova. But instead of progressing to a tremendous explosion, the star suddenly disappeared. Thinking that the star had perhaps been hidden by a cloud of dust, Scott Adams of Caltech and his colleagues used the Hubble Space Telescope to examine the region of sky. Where the star had been, they found a faint IR signature, which they believe is evidence of material falling into a black hole that formed via the star's collapse. If the interpretation is correct, then this is the first star known to have become a black hole without first going supernova. Such a process has been described in theories that say some stars are so massive that the supernova process cannot overcome the stars' own gravity. If the star did become a black hole, the debris falling in is likely emitting x rays. Adams's team is awaiting observations from the Chandra X-Ray Observatory.

New record set for quantum teleportation

20 September 2016
New Scientist: Two research teams have separately demonstrated the transfer of quantum information over several kilometers of fiber-optic cables. Both setups involved three hypothetical participants: two who want to securely share information via quantum-entangled particles, and a third who serves as an intermediary by intercepting and measuring the particles such that their quantum states get swapped and the information they carry is transferred. By varying the position of the participant who entangles the particles, the two research teams achieved slightly different results. Wolfgang Tittel of the University of Calgary in Alberta, Canada, and his colleagues sent quantum information over a distance of 6.2 km, while Jian-Wei Pan of the University of Science and Technology of China and his colleagues were able to extend the distance, to 12.5 km. The next step is to scale up such systems so they could provide secure communications over arbitrarily long distances.

Warhead upgrade costs could spiral, report warns

20 September 2016
Auditors urge further steps to tighten management controls over an $8 billion program to extend the life of a 1960s-era bomb.

Canada to charge provinces for carbon emissions

19 September 2016

Reuters: On 18 September Canadian environment minister Catherine McKenna announced that the government would put a price on carbon emissions from any of the country's provinces that do not adequately regulate emissions themselves. The policy will go into effect in October, McKenna said. She did not provide details about how the price would be set, what efforts the provinces are expected to make, or how the government would enforce the payments or penalties. She also did not address whether the current government would be altering the previous government's pledge to cut emissions to 30% below 2005 levels by 2030, a target that is likely unreachable without significant efforts by both the national and provincial governments.

Graphene membranes’ anomalous dynamics

19 September 2016
The ability to tune the random fluctuations could be used to minimize them or to harness them.

Rising carbon dioxide levels are good for plants—until the temperature increases

19 September 2016

Guardian: A common claim from those disputing the hazards of anthropogenic climate change is that rising carbon dioxide levels have led to increased global plant growth. There is some evidence supporting that claim. However, a new paper suggests that now that the global CO2 concentration has surpassed 400 ppm, the detrimental effects of rising temperatures will outweigh the benefits of further CO2 increases. Between 1998 and 2014, researchers at Stanford University grew 132 plots of common California flowers and grasses and varied the temperature, water, and CO2 and nitrogen levels. The results showed that plant growth increased with higher concentrations of nitrogen and decreased with rising temperatures. But beyond current global atmospheric levels, CO2 had no notable effect on plant growth.

NASA collaborates with artist to depict melting glaciers

19 September 2016
New York Times: Artist and photojournalist Justin Guariglia will be going along for the ride as part of NASA’s Oceans Melting Greenland mission. Guariglia has already captured a number of aerial landscape photographs of Greenland’s glaciers and sea ice, which he took from a military transport plane window on a 2015 NASA flight. He has since turned those images into three-dimensional representations through the use of ink-jet printing. The purpose is to find new and inventive ways to present the effects of climate change to the public. Some of Guariglia's images are set to go on display in 2017 in a solo exhibition at the Norton Museum of Art in West Palm Beach, Florida. Guariglia will be going on more low-altitude flights to Greenland through 2020.

Climate research paper published under fake names stirs controversy

19 September 2016
Washington Post: A paper published in the journal Advances in Space Research has been withdrawn following the revelation that the authors used pseudonyms. Ned Nikolov and Karl Zeller, independent researchers, had developed a mathematical model for calculating a rocky planet’s surface temperature. According to their model, Earth is warming not because of human activities but because of solar radiation and Earth’s atmospheric pressure. However, due to the controversial nature of their assertion and the heated discussions that an earlier paper of theirs had caused, they worried that no journal would publish the study. So they submitted and published their paper under the names Den Volokin and Lark ReLlez, their actual names spelled backward. Although the pair claim they only wanted to avoid the bias inherent in the peer-review system, their use of fake names has been denounced by fellow researchers as being “sneaky.”

Converting light to sound for manipulating data

16 September 2016

Ars Technica: Light moves too quickly for computer chips to process it. By the time a chip has determined how to route data encoded in light, the pulse has already passed by. To prevent signal loss, chips divert the light pulses and store data electronically, but that is a slow and inefficient process. Now a team of Australian researchers has developed a way to briefly slow down the light: They convert the light pulses into sound pulses and then back again. The technique isn't new—it's commonly used in lasers—but adapting the idea for data transmission required finding a way to create and propagate the sound waves with minimal data loss. The researchers converted a standard light pulse and then collected the signal with the full data load 3.5 ns later, which is a significant slowdown in transmission that doesn't require storing the data electronically.

WMO reports two record-setting lightning bolts

16 September 2016
Science: New world records for the longest reported distance and the longest reported duration of single lightning flashes have been announced by the World Meteorological Organization (WMO). The distance record is 321 km, set on 20 June 2007 by a bolt of lightning that originated just south of Tulsa, Oklahoma, and traveled westward toward the Texas border. The duration record is 7.74 seconds, set by a lightning flash that occurred on 30 August 2012 over Provence-Alpes-Côte d'Azur, France. Validation of these new extremes demonstrates the improvements in regional lightning detection, according to the WMO.

Arctic sea ice minimum in 2016 ties for second lowest on record

16 September 2016

Washington Post: In May 2016, Arctic sea ice levels were lower than they were at the same time in 2012, which is the year levels dropped to the lowest minimum coverage ever recorded. That finding did not bode well for Arctic ice levels this year. However, increased cloud cover over the summer appears to have had a cooling effect on the region, as preliminary measurements of the minimum level for 2016 show it is only the second lowest ever recorded. The 2016 minimum, reached on 10 September, was 4.1 million km2 (1.6 million mi2).

China successfully launches space lab Tiangong 2

16 September 2016
Nature: On 15 September at 10:04pm local time, China launched Tiangong 2 into low-Earth orbit. The space lab is to replace Tiangong 1, China’s first prototype space station, which has been in orbit since 2011. In November China plans a second launch to send two astronauts up to Tiangong 2 for a one-month stay, and in April 2017 another craft will bring fuel and more supplies. Onboard Tiangong 2 are 14 experiments, including POLAR, an international mission to study high-energy photons from gamma-ray bursts. Over the past year, China has also launched DAMPE, its first dark-matter detector, and QUESS, the world’s first quantum communications satellite.

American officials are negotiating with Turkey for release of NASA physicist

16 September 2016
Serkan Golge is the only US citizen who was arrested for alleged involvement in the July coup attempt.

How typhoons change the underwater sound field

15 September 2016
By warming seafloor sediment, typhoons reduce the transmission of sound in coastal waters.

UK approves Hinkley Point nuclear plant

15 September 2016

BBC: The UK government has approved an £18 billion ($24 billion) project to construct a nuclear power plant at Hinkley Point in Somerset, England. The project is being financed by the French and Chinese governments. As part of the agreement, the UK can prevent EDF, France's state-controlled energy firm, from selling its stake in the project. EDF is providing two-thirds of the funding for the project, which is expected to create more than 25 000 jobs. The Chinese investment also included an agreement for the development of a new nuclear plant at Sizewell in Suffolk and an understanding that the UK would approve another Chinese-led project at Bradwell in Essex. The 3.2 GW Hinkley Point power plant will satisfy roughly 7% of the UK's energy needs.

EU announces plan to eliminate copyright restrictions for data mining

15 September 2016

Nature: Researchers who want to collect data from published papers often rely on software to scrape the information. However, for researchers in the European Union (EU), paywalled content and copyright restrictions hamper their ability to do so. Now, the European Commission has proposed that text and data mining be exempted from copyright for research organizations, such as universities, that have legal access to the research. The proposal should alleviate the concerns of many European researchers, who, according to an EU report, perform less data mining than their American and Asian counterparts.

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