Physics Today Daily Edition
Nature: Simulations of phenomena involving the strong nuclear force are too hard to perform from first principles on classical computers. Now Esteban Martinez of the University of Innsbruck in Austria and his colleagues have used a quantum computer to complete a proof-of-concept simulation of the conversion of energy into an electron and positron pair. It's the first time a quantum computer has been used to simulate a high-energy physics experiment. The simulation matched the predictions of a simplified form of quantum electrodynamics. The quantum computer contained four qubits in a linear arrangement. Martinez's team now hopes to use a two-dimensional arrangement of qubits and scale up the simulation.
Nature: The Square Kilometre Array (SKA) is an international radio telescope being built in Australia and South Africa. Construction of the first of 197 radio dishes has already begun in South Africa's Northern Cape province, a sparsely populated area of mostly farmland. The SKA project is now facing protests from local residents as the organization begins to purchase more land to construct the majority of the dishes. The SKA organization's initial outreach to the community focused on how the project would create jobs and improve economic and educational opportunities. It currently is providing support for new teachers in nearby Carnarvon and is paying tuition for some students to attend universities. But the benefits have not been evenly distributed among the local communities. Additionally, residents are concerned that the loss of farmland will damage the local economy.
Ars Technica: Over the past several years, the success of the US's Global Forecasting System (GFS) weather model has been challenged by the rise of other models, such as one put out by the European Centre for Medium-Range Weather Forecasts. The competition between models first reached broad popular awareness in 2012, when the European model more accurately predicted the behavior of Hurricane Sandy. In a widely accepted measurement of forecast accuracy, the GFS model has now fallen behind not only the European model but also models from the UK and Canada, based on predictions over the past two months in the Northern Hemisphere. According to Cliff Mass of the University of Washington, the drop in ranking isn't because the GFS model is failing but because the other models have improved significantly.
NPR: The Diablo Canyon Nuclear Power Plant is the last nuclear plant still operating in California. On 21 June Pacific Gas and Electric announced that it would close the plant by 2025 and replace it with renewable energy sources. Diablo Canyon provides energy to 1.7 million homes. Local residents and environmental groups have continually raised safety concerns because the plant and its two nuclear reactors are close to active fault lines. Protests intensified following the earthquake and tsunami that damaged Japan's Fukushima Daiichi Nuclear Power Plant in 2011.
GeekWire: Trevor David of Caltech and his colleagues have spotted an intriguing planet orbiting K2-33, a star in the field of view of the Kepler space telescope during its extended K2 mission. The planet has a diameter about six times that of Earth, and it orbits its star every 5.4 days at a distance of 7.4 million km. Further examination of the system revealed that the star is still surrounded by gas and dust from the protoplanetary disk. The presence of the disk's remnants suggests that the planet is less than 10 million years old, since models of planetary system evolution predict that disks dissipate fairly quickly. Now researchers have to figure out why the youthful planet is so close to its star; most models suggest that large planets form far away and then migrate inward later.
BBC: China's new Sunway TaihuLight supercomputer at the National Supercomputing Center in Wuxi has first place on Top500's latest list of the world's most powerful supercomputers. At 93 petaflops (93 trillion floating point operations per second), the computer is twice as fast as the previous top computer—China's Tianhe-2—and three times as efficient. Sunway TaihuLight will be used primarily for advanced manufacturing, weather forecasting, and data analytics. For the first time, China has surpassed the US in the number of computers on the Top500 list, 167 to 165. China has two machines in the top 10—the top two. However, the US holds four of the first 10 spots.
IEEE Spectrum: The systems for managing cryptocurrencies such as Bitcoin are intended to be secure. But as with all software systems, there are flaws that some users attempt to exploit. On 17 June a public investment system called the DAO, which is built around the Ether currency, was exploited in a way that allowed the attacker to steal more than 3 million Ether (at the time equivalent to about $60 million). Participants in the DAO use Ether to purchase DAO tokens, which give them proportional ownership of the DAO and a proportional vote in the group's investments. The DAO is designed so that token holders can split off their shares and invest them for 27 days before returning the currency to the collective pot. The attacker managed to split away more than his or her original share of the collective investment. The person behind the attack now controls a split DAO that contains 100 times as many tokens as initially invested. Those surplus tokens were taken away from other investors. The developers behind the DAO are looking for a solution. Other than resetting the system to a point before the attack began, which is counter to the principles of block-chain currencies, there does not appear to be a way to restore the stolen funds to the original owners.
New York Times: On 17 June NASA administrator Charles Bolden announced that the agency is developing an all-electric airplane. Designated the X-57, the relatively small plane will have 14 motors embedded in its wings and a cruising speed of around 282 km/hr. Only two of the motors—60 kW each, driving 1.5 m propellers—will be used while the plane is cruising. The other dozen motors, 9 kW each and driving 0.6 m propellers, will be used during takeoff and landing; the propellers will be folded away when unused. The additional propellers are necessary because the wings are much narrower than traditional wings, which makes them more efficient for cruising but less so for takeoff. The project is starting from an extant plane, the four-seat Tecnam P2006T. The conversion will entail replacing the passenger seats with battery packs and adding instruments for the pilot. The battery capacity should allow the plane to be airborne for about an hour; NASA is investigating the use of fuel cells instead of batteries to increase the flight time. The agency also expects to be able to scale up the technology for commuter and regional airlines.
NPR: On 16 June Russia launched the Arktika, a 173 m icebreaker powered by two nuclear reactors. Designed to break through ice up to 4 m thick, the Arktika is part of Russia's growing Arctic naval development, which includes building new bases in the Arctic Circle and modernizing nuclear submarines. Russia is the only country with nuclear-powered icebreakers. It already has more icebreakers—over two dozen—than all other nations combined.
Thanks to geometric tricks, behavior associated with massive, charged particles can emerge in an ordinary beam of light.