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Updated: 10 min 38 sec ago

Pacific tectonic plate may have grown from a single point

28 July 2016
Science News: The largest of Earth’s tectonic plates may actually have started out as the smallest, according to a new study in Science Advances. Unlike the other modern plates, which formed when ancient plates split into two, the Pacific Plate may have grown from a single point located at the junction of three older plates. Lydian Boschman of Utrecht University in the Netherlands and her colleagues say that at some time one of the three plates overlapped another one, causing a piece to break off and get pushed under the rest. That event created the three-way junction, around which the plates proceeded to glide past each other in a pinwheel motion rather than pull apart. As the gap widened, molten rock flowed up into the void, and the plate formed and grew.

A path to better lithium-ion battery performance

28 July 2016
Engineering electrode structures straightens the tortuous route that ions must travel.

NOAA takes first step toward developing new global weather model

28 July 2016
Washington Post: The US National Oceanic and Atmospheric Administration has announced that it is updating its Global Forecast System (GFS) weather model. The new GFS will feature the FV3 dynamic core created by NOAA’s Geophysical Fluid Dynamics Laboratory. The FV3 was chosen over other candidates primarily because of its computational efficiency, which is essential for running all the necessary weather and climate models. NOAA says the goals are to improve forecast accuracy beyond 8–10 days, to better model forecasts of hurricanes and their intensity, and to extend weather forecasts to 14 days in advance and extreme event forecasts to 3–4 weeks in advance. Now that a core has been selected, the next steps are to test and improve the weather-predicting algorithms and develop a method to assimilate all the data from satellites, weather balloons, and ground-based observations.

Atmosphere over Jupiter’s Great Red Spot is surprisingly hot

28 July 2016
New York Times: Despite Jupiter’s distance from the Sun, its upper atmosphere is extremely hot, several hundreds of degrees hotter than simulations have predicted—and the atmosphere above the planet's Great Red Spot is even hotter. To try to determine where the heat is coming from, James O’Donoghue of Boston University and his colleagues used the NASA Infrared Telescope Facility in Hawaii to examine the emissions of a particular hydrogen ion that is abundant in Jupiter's atmosphere. Based on the emissions’ brightness, the researchers say the heat is probably coming from below the Great Red Spot, perhaps in the form of acoustic or gravity waves that rise and crash in the upper atmosphere.

Royal Society president calls for UK to guarantee continued funding for EU-funded research

27 July 2016
BBC: In the wake of the Brexit referendum, the head of the Royal Society says that he wants the British government to underwrite funding for UK-based researchers who are applying for EU research grants. In an interview, Venki Ramakrishnan said that some UK researchers are already being excluded from EU collaborations because of uncertainty over the effect of Brexit on the researchers' status and grant funding. To avoid that loss of access, Ramakrishnan said the UK should guarantee the continuation of any funding that UK-based researchers receive from the EU for the duration of the grant.

Lawsuit alleges sex discrimination in university physics lab

27 July 2016
Science: An undergraduate student at the University of Cincinnati in Ohio recently filed a lawsuit over alleged sex-based segregation in the school's science courses. Casey Helmicki says that in the physics course she took in the fall of 2015, she was told that lab groups are deliberately arranged to group women students together because “women shouldn’t be working with men in science.” The professor for the course, Larry Bortner, declined to comment on the suit. But he has stated in emails that he does instruct his lab assistants to try to arrange the women students in predominantly female groups, because studies have shown that “females do better in small lab groups (three or four) that contain more females than males.” Helmicki counters, however, that such gender discrimination violates Title IX of the US Education Amendments of 1972.

3D mapping of Ceres reveals remnants of large craters

27 July 2016
New Scientist: Simulations of the history of Ceres suggest that the dwarf planet should have 10 to 15 impact craters larger than 400 km across. Yet early images from NASA's Dawn spacecraft, which has been in orbit around Ceres since March 2015, did not reveal any such craters. Now, Simone Marchi of the Southwest Research Institute in Colorado and his colleagues have created a three-dimensional model of Ceres from high-resolution images taken by Dawn. The model reveals large depressions on the surface of Ceres that Marchi and his team believe are the remnants of the expected craters. They suggest that Ceres's unusual internal structure could be the reason for the smoothing. It is thought that Ceres's surface hides a layer of mud that allows the outer layer to shift and relax, which Marchi's team says would eliminate the telltale signs of large craters.

Motion of stars in ultradiffuse galaxy measured for first time

27 July 2016
Nature: Since the discovery last year of 47 extremely dim galaxies in the Coma cluster, hundreds more have been observed there and elsewhere. Such ultradiffuse galaxies (UDGs) are thought to be as large as the Milky Way but emit much less light. Now Pieter van Dokkum of Yale University and Roberto Abraham of the University of Toronto in Canada and their colleagues have focused on one of the largest and brightest of the UDGs, called Dragonfly 44. From measurements of the galaxy’s spectral line, the researchers have been able to determine that Dragonfly 44's stars are moving very quickly relative to one another, at some 47 km/s, which indicates the galaxy is massive, perhaps a trillion times as massive as the Sun. Despite what has been learned so far about UDGs, their origin remains a mystery.

Transistors may stop shrinking in five years

26 July 2016

IEEE Spectrum: Moore's law describes a historical trend concerning the density of transistors on computer chips, which has been doubling roughly every two years since the 1970s. The primary driver has been the continuing reduction in transistor size. However, a new analysis of transistor technologies suggests that by 2021 manufacturers will no longer find it economically viable to decrease the dimensions of transistors any further. The analysis, included in the 2015 International Technology Roadmap for Semiconductors, suggests that manufacturers will probably continue to be able to increase transistor density by layering transistors vertically.

Analysis shows droughts shut down Amazon carbon sink

26 July 2016

BBC: The Amazon basin is one of the world's largest carbon reservoirs, with the plants there holding roughly 17% of Earth's vegetation-stored carbon. A new study has revealed, however, that two recent droughts have adversely affected the basin's ability to absorb carbon. According to coauthor Ted Feldpausch of the University of Exeter, UK, during one of the droughts, in 2010, the rate of vegetation mortality increased and the growth rate slowed, which resulted in the region releasing more carbon than it was taking in. In nondrought years, the region absorbs hundreds of millions more tons of carbon than it loses.

Last universal common ancestor of all living things may have sprung from deep-sea vents

26 July 2016
New York Times: Three principal domains of life have been identified on Earth: bacteria, archaea, and eukaryotes. Of those, bacteria and archaea are thought to have originated first. By looking at the protein-coding genes of bacteria and archaea, William Martin of Heinrich Heine University in Germany and his colleagues now say they have identified the ancient organism from which both are descended. Called Luca, the last universal common ancestor may have lived about 4 billion years ago and appears to have developed in the intensely hot deep-sea vents where magma erupts through the ocean floor. Martin’s further claim that Luca may have been very close to the origin of life itself, however, has provoked controversy because of the organism's apparent ability to synthesize proteins, generally considered to be a fairly complex task.

<em>Solar Impulse</em> completes first solar-powered round-the-world flight

26 July 2016
BBC: After traveling for more than a year and making some 17 stops along the way, Solar Impulse 2 has successfully completed the first-ever circumnavigation of Earth by a solar-powered aircraft. The plane touched down earlier today in Abu Dhabi, United Arab Emirates, where it had begun its historic journey on 9 March 2015. The project was the brainchild of André Borschberg and Bertrand Piccard of Switzerland, who took turns piloting the craft on its 42 000 km journey across four continents, three seas, and two oceans. Over the course of the trip, the two set 19 official aviation records, including longest uninterrupted solo flight when Borschberg flew 8924 km from Nagoya, Japan, to Kalaeloa, Hawaii.

The formation of the Martian moons

25 July 2016
A new simulation strengthens the case that Mars’s two satellites condensed out of a long-gone debris disk that surrounded the planet.

China ramps up space missions

22 July 2016

Science: China's space program has set an ambitious schedule as it tries to be seen as an equal partner to NASA and the European Space Agency (ESA). The schedule includes launching more than four missions over the next 13 months. Moreover, the country's lunar exploration program hopes to launch a sample return mission next year, and its first-ever landing on the far side of the moon is planned for 2018.  Beginning in 2020 China will launch four science missions and the nation's first Mars probe. Unlike NASA or ESA, the Chinese space program doesn't receive annual funding but instead gets one lump sum every five years. That arrangement doesn't adjust for inflation or allow for last-minute plan changes. In addition, the country's different space agencies are competing for scarce resources and missions. The solution, say Chinese space administrators is to merge agencies into one.

Most comprehensive map of human brain reveals 97 new regions

21 July 2016
New York Times: After more than a century of study, the most detailed map of the human brain to date has been created, revealing almost 100 previously unknown regions. To create the map, Matthew Glasser of the Washington University School of Medicine and colleagues spent the past three years analyzing data collected by the Human Connectome Project. They combined high-resolution images of multiple aspects of the brain, including structure, function, and connectivity, which were captured as the subjects participated in various activities or simply rested. With the use of artificial-intelligence software, the researchers were able to identify not only 83 known regions in the brain but another 97 that were previously unknown or forgotten. The new, state-of-the-art map is expected to help not only brain surgeons in the operating room but also researchers to better understand brain development, aging, and brain-related disorders, such as Alzheimer’s.

Dark matter remains to be seen

21 July 2016 Despite its recent 20-month run, the Large Underground Xenon (LUX) experiment has yet to detect a dark-matter signal. LUX is just one of several experiments currently seeking signs of the weakly interacting massive particles (WIMPs) that make up some 85% of the mass of the universe. Located at the Sanford Underground Laboratory in South Dakota, LUX features a large tank of liquid xenon, whose high density makes it more likely to interact with WIMPs. Although LUX has so far failed to detect the elusive particles, the data it gathered can still be used to improve the design of future, more sensitive experiments. LUX itself is soon to be replaced with the LUX-Zeplin detector, which will be 70 times as sensitive.

Underwater microscope brings marine life into focus

21 July 2016
Some of the ocean’s smallest organisms can now be observed in their natural habitat.

High-energy lab has high-energy director

21 July 2016
CERN director general Fabiola Gianotti looks at what lies ahead for particle physics.

Facebook developing high-speed laser-based Wi-Fi

20 July 2016
PC World: Although wireless networks provide internet connectivity without the need to run physical cables, the systems can be slow, and they rely on available radio spectra. To overcome those problems, researchers at Facebook have been working on a system that uses lasers to transmit data. Because laser beams dissipate as they travel, however, a very large detector is required to collect the signal. Facebook has developed a cheap, large detector through the use of plastic optical fibers doped with organic dye molecules. Its 126 cm2 detector is thousands of times larger than earlier designs. Facebook’s prototype device has achieved 2.1 Gbps, and the company hopes to speed it up even more by switching to UV light. Such a system could be used to transmit high-definition video to mobile devices and provide low-cost communications in remote areas.