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Updated: 1 week 12 hours ago

Learning the rules of kirigami

24 November 2014
Sophisticated science underlies the art of cutting, folding, and pasting lattices.

Flash memory created from single molecule

21 November 2014

Ars Technica: A tiny flash memory chip has been created from molecules of selenium trioxide enclosed in a cage-like structure of tungsten oxide. Because the molecules and the cage can exchange electrons and form bonds, the material is capable of holding an electrical charge. To test it, researchers covered a wire with a single layer of the caged molecules and applied a large negative voltage. Not only did the electrons stay in place for 336 hours, but the application of a smaller voltage allowed the electrons to be read out, and a large positive voltage returned the device to its original state. Although the write and read speeds are slower than those of current memory devices and require higher voltages, the researchers propose that improving the design could also improve the performance.

Sound-altering app could improve user’s mental state

21 November 2014

Telegraph: Sound can affect not only people’s self-perceptions about body shape but also their physical capabilities, according to scientists at University College London. The phenomenon has to do with how the brain works: Rather than passively receiving acoustic and other sensory input, a person’s brain is constantly using that information to update and modify one’s sense of self. To better understand that ability, the researchers created a pair of sandals linked to headphones that change the sound of the wearer’s footsteps. By manipulating the sound a certain way, the researchers could make the wearer feel lighter and able to move more quickly. Now the researchers are working on an app to achieve much the same effect. They say it could have myriad uses, such as helping athletes to train for longer periods of time and encouraging depressed people to leave their homes and socialize more.

Bernard Bigot named next ITER director general

21 November 2014

Science: The ITER international prototype fusion reactor, which is under construction in southern France, will be getting a new director general next year. Bernard Bigot, currently general administrator of France’s nuclear power company CEA, will take over from Osamu Motojima as ITER’s third director general. In this interview with Science, Bigot says his biggest challenges as director general will be getting ITER’s central organization and its seven domestic agencies to work more as a team, bringing ITER’s construction schedule back on track, and reassuring the US and other member countries concerning the rising costs of the project.

New solar panel system promises to be cheaper, easier to install

21 November 2014

MIT Technology Review: Because of the complex hardware, permitting, and technical expertise required, rooftop solar panel systems have been prohibitively expensive to install. But a new, simplified system designed by the Fraunhofer Center for Sustainable Energy Systems may change all that; it has flexible panels with an adhesive backing and an innovative power distribution arrangement. The lighter design should allow homeowners to install the panels themselves by simply gluing them to the roof and hooking them up via a series of quick-connect cables. The power will be controlled and distributed via packet energy transfer (PET), an innovative electrical system being developed by the Rhode Island startup company VoltServer. The system is being marketed as much safer than conventional power delivery because its software performs safety checks and can cut off or reroute the power instantly if it senses a problem. The system is currently in the beta testing phase.

Pollution versus prosperity

21 November 2014
Radar altimetry reveals a threat to marine ecosystems and a boom in maritime trade.

Two new particles discovered at LHCb

20 November 2014

CBC News: Researchers analyzing data collected by CERN's LHCb experiment have found two new particles, Xi_b'- and Xi_b*-. Both particles are baryons, meaning they are each made up of three quarks, just like protons and neutrons. The new particles are six times heavier than a proton because they each contain the extremely heavy bottom quark. The existence of the particles did not come as a surprise as they had been predicted by two researchers in Canada: Randy Lewis of York University in Toronto and Richard Woloshyn of the TRIUMF particle-physics lab in Vancouver. The two particles join the very long list of baryons and are the third and fourth particles discovered at the LHC: The Higgs boson was identified last year, and another baryon, the Xi_b*0, in 2012.

Potential supernova may actually be a black hole

20 November 2014 A bright object called SDSS1133, located just outside a dwarf galaxy known as Markarian 177, has long been thought to be a supernova. However, Michael Koss of the Swiss National Science Foundation has discovered that images of the object show that it has remained bright for more than 60 years, much longer than any known supernova. Recent observations have also revealed that SDSS1133 is getting brighter. Because supernovas tend to explode in a bright flash and then fade over time, Koss and his colleagues propose that SDSS1133 may actually be a black hole. It could have been created when two galaxies collided and their central black holes merged. To determine whether SDSS1133 is indeed a black hole, the researchers are looking for the presence of a specific form of carbon in the surrounding material.

3D printing used to construct smart contact lens

20 November 2014

New Scientist: Researchers are finding that 3D printing may be more versatile than previously thought. Michael McAlpine of Princeton University and his colleagues have succeeded in 3D printing contact lenses that contain quantum-dot LEDs. To do so, they had to integrate five different types of materials and print them onto a curvilinear surface. The finished lens is a transparent polymer that contains the nanoscale LEDs along with silver nanoparticle wiring and organic polymers that form electrical circuits. The US Air Force is funding the project, which could have many uses, including the display of in-flight data and, if sensors were incorporated into the design, the monitoring of pilot health and fatigue. More testing is needed to make sure that the materials used—such as the cadmium selenide in the LEDs—will have no adverse effects on the wearer.

Private Moon mission seeks Kickstarter funding

20 November 2014

Nature: A UK consortium is setting its sights on launching a $1 billion mission within the next 10 years to explore the Moon's south pole. Called Lunar Mission One, it would land an unmanned spacecraft on the Moon’s surface, drill a 5-cm-diameter borehole to a depth of 20–100 m, and analyze the rock samples it collects. For funding, the project's developers have turned to Kickstarter, through which they hope to raise an initial $1 million by 17 December. In an effort to attract prospective sponsors, they are promising space for digital photos, personal messages, and so forth to be placed in a time capsule that will be buried on the Moon. Although skeptics doubt that enough people will be interested to raise the $1 billion total that will be needed for launch, Lunar Missions founder David Iron says there’s “no harm in finding out.”

Precision plasma wakefield acceleration

20 November 2014
In a tabletop accelerator, electrons must be positioned in a region of high electric field.

New laser technique allows analysis of smaller geological samples

19 November 2014

Ars Technica: Analyzing sediment and ice cores has usually required removing chunks of material and taking them to a laboratory for study. One form of chemical analysis involves lipid molecules, which aren’t easy to measure with the necessary precision. Now a group of researchers led by Lars Wörmer of the Center for Marine Environmental Sciences at the University of Bremen in Germany has developed a method using lasers that can get much more detailed results from much smaller samples of material. When aimed at a sample, the laser stirs up microscopic clouds of molecules that can then be analyzed by a mass spectrometer. In a side-by-side comparison with traditional techniques, the laser method not only showed comparable results but also detected more detail, such as the fact that sea surface temperatures appear to vary more in the short term than was previously believed. Next the researchers hope to turn their laser technology onto other organic molecules in sediment in order to learn even more about past climates and ecosystems.

<em>Philae</em> returns its first data from the surface of a comet

19 November 2014

BBC: Despite its bumpy landing on comet 67P/Churyumov–Gerasimenko, the European Space Agency's Philae lander was still able to perform its primary scientific missions. One of its instruments sampled and analyzed the comet's atmosphere and detected the presence of organic molecules. The team monitoring that instrument has not revealed any details about what compounds were found or in what concentrations. A second instrument suggests that the comet is covered by a layer of dust 10- to 20-cm thick with frozen water underneath. Because of the extreme conditions at which it froze, the ice appears to have a tensile strength similar to that of sandstone. A drill that was supposed to obtain a soil sample and deliver it to an analyzer appears to have failed to do so. Also, an x-ray spectrometer designed to image the comet's surface appears to have failed to take clear pictures, probably due to the fact that the lander ended up lying on its side.

Mystery Russian spacecraft is making unusual maneuvers

19 November 2014
New Scientist: A rocket launched 23 May from the Plesetsk Cosmodrome in Russia released four spacecraft. Three of those craft are believed to be military communications satellites. The fourth is something of a mystery. Instead of settling into a stable orbit like the other spacecraft, it has been changing course repeatedly and on 28 October approached the rocket that put it into orbit. Those sorts of maneuvers are mostly associated with two types of spacecraft: satellite repair robots and antisatellite weapons (ASATs). Russia officially stopped developing ASATs in the 1980s, but in 2010 Russian space commander Oleg Ostapenko said that the country had begun work on the technology again in response to rising tensions between Russia and Western nations.

Gecko-inspired adhesive allows human to scale wall

19 November 2014

MIT Technology Review: Geckos are known for their ability to adhere to and climb vertical surfaces, including sheer ones like glass. They can do so because of the stickiness of their feet, which is due to the weak electrical attraction called van der Waals forces between the surface and the hair-like setae on gecko footpads. Now researchers led by Mark Cutkosky of Stanford University have developed a human climbing system based on the structure of gecko toes. They attached tiles of an adhesive polymer material called PDMS to a flat, hexagonal, hand-sized gripper backed with a spring to distribute the user's weight across the pad. The system allowed a 70-kg graduate student using two of the grippers to scale a vertical glass wall. So far, however, the climbing system has been tested only on very smooth, clean, flat surfaces. If it is to be put to practical use, such as by construction workers for manipulating huge solar panels or by the military for maneuvering in difficult terrain, it will need to be tested under less ideal conditions, such as on wet or dusty surfaces or in zero gravity.

Revision promoted for conventional wisdom about Solyndra

19 November 2014
A widely covered new report suggests that overall, Energy Department green-technology loans have succeeded.

India may pose biggest challenge to curbing global climate change

18 November 2014

New York Times: To power its burgeoning economy, India has been pushing to harvest its vast stores of domestic coal. The country has the fifth-largest coal reserves in the world and very little oil or natural gas. However, the coal is twice as polluting as that from Western nations because of its high ash content, and 90% of it comes from strip mines, which are laying waste to the land, water, and air. As a result, smog levels in India have become worse than China’s. Yet the country’s power minister, Piyush Goyal, has pledged to double the use of domestic coal by 2019. Nevertheless, one promising alternative is being pursued by Prime Minister Narendra Modi, who is working to take advantage of another of India’s natural resources: sunlight. Modi is currently pushing for arrays of solar power stations, one of which has already been built by Welspun Energy and is the largest so far in Asia. Whether solar power will keep India from pushing the world past the brink of irreversible climate change remains to be seen.

ASA fall 2014: Uncanny acoustics at a Peruvian archaeological site

18 November 2014
Strange architectural sound effects may have led ancient musicians to believe their instruments were controlled by phantom forces.

GPS satellites could provide clues for dark-matter detection

18 November 2014

New Scientist: The network of GPS satellites is nearly 50 000 km in diameter, and each satellite is equipped with a very precise clock. Along with Earth and the rest of the solar system, the GPS network travels through the galaxy at nearly 300 km/s. Andrei Derevianko of the University of Nevada, Reno, and Maxim Pospelov of the Perimeter Institute in Waterloo, Ontario, Canada, argue that this combination of factors makes the network a potentially useful tool for detecting a version of dark matter that may not consist of particles. They propose that dark matter could instead take the form of bends or cracks in the quantum fields that fill the universe. As the solar system passes through one of those cracks, it is possible that the GPS network would detect a variation in the satellites' clocks. The effect would appear as a wave that spreads across the network at the rate of the solar system's movement. Derevianko is now examining 15 years' worth of GPS data to look for such a signal. If his initial search is unsuccessful, he plans to use a network of ground-based atomic clocks currently being built in Europe, which will be even more sensitive than the satellites' clocks.

Europe to provide <em>Orion</em>'s first service module

18 November 2014

BBC: Orion is NASA's next-generation manned space capsule that is currently under development. NASA has now signed an agreement with the European Space Agency (ESA) and Airbus, which will work together to create a propulsion and service module for Orion's first full test flight, scheduled for 2017. The module will be developed by Airbus with €390 million ($490 million) in funding from the ESA. NASA will receive the module for free as the ESA's payment in kind for costs the ESA will incur at the International Space Station (ISS) between 2018 and 2020. The service module design was heavily influenced by the ESA's Automated Transfer Vehicle, an unmanned craft currently being used for cargo deliveries to the ISS.