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Updated: 4 hours 59 min ago

Arrays of nanoscale metallic fins could replace high-end optical lenses

3 June 2016
New Scientist: Although curved optical lenses are ubiquitous in telescopes, microscopes, and cell phone cameras, the size of those devices is limited by the thickness and weight of the glass. Now researchers have used metamaterials to create a lens that is thinner than the wavelengths of the light waves it focuses. The scientists carved tiny blocks of titanium dioxide, rotated them at different angles, and mounted them on a thin piece of glass. Each 600-nm-thick lens, which was tuned to either red, green, or violet light, achieved sharper focus than a 55-mm-thick Nikon lens, with minimal loss of light. Next the research team plans to expand the range of color the lenses can detect.

Hawking revisits his 40-year-old theory regarding black holes and causal determinism

3 June 2016
Economist: In the mid 1970s, physicist Stephen Hawking challenged the theory of causal determinism by proposing that information could be lost forever if matter were sucked into a black hole because the black hole would eventually disintegrate. Now, however, he has revised that idea and shows how the evaporation of black holes does not necessarily mean that all the information contained in the swallowed matter will be destroyed. Hawking instead proposes that when matter falls into a black hole, it leaves traces of the information it contained in the form of the number and position of two soft particles, photons and gravitons. The informational record remains even after the black hole has disappeared. Although the explanation is incomplete because it accounts for only one property of matter—its electric charge—the principle supports the established laws of physics and could lead to a more complete understanding of black holes and the universe.

Experiments relating to Earth's inner core raise questions about its age

2 June 2016
Measurements of iron's thermal conductivity hint that the planet's solid center is relatively young—and not responsible for Earth's dynamo long ago.

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2 June 2016

Rising air conditioning use could exacerbate global warming

2 June 2016
Washington Post: As the world’s population grows and countries’ economies improve, more people are purchasing air conditioning units for their homes and businesses. According to a study published last year, as many as 1.6 billion new air conditioners could be installed by 2050. To discuss the global impact on climate those installations will have, representatives from around the world are meeting in San Francisco this week at the seventh Clean Energy Ministerial. They will consider ways to lessen the environmental impact, such as by designing air conditioners to be more energy efficient and by finding alternative coolants to hydrofluorocarbons, which contribute to global warming.

Record-long rail tunnel opens in Switzerland

2 June 2016
BBC: Measuring 57.1 km in length and requiring 17 years to build, the Gotthard Base Tunnel cuts through the Swiss Alps to connect northern and southern Europe. The tunnel is flatter, straighter, and deeper than a previous one built in 1980, and its purpose is to expedite the transport of both people and goods across the Alps. Some 65 passenger trains and 260 freight trains will use the tunnel daily. It is expected to help reduce the number of trucks traveling through Switzerland, which has been estimated to be as many as a million per year.

Decline of US nuclear industry is accelerating

1 June 2016
New electricity pricing policies are needed to help nuclear plants remain open and allow them to compete with cheap, abundant natural gas, officials say.

<em>Wall Street Journal</em> trumpets "explosive finding" on cell phones and cancer

1 June 2016
Journalists must decide: Should new research "dramatically shift the national debate over cell phone safety"?

Fleet of minuscule “chipsats” to launch in July

1 June 2016
Nature: On 6 July some 100 chipsats, or tiny cubesats, are to be sent up into orbit near the International Space Station. Each chipsat measures just 3.2 cm2 in area and weighs about 5 g. They are to be deployed en masse from a KickSat satellite and, once in place, will use a radio, an antenna, and a pair of 60 milliamp solar cells to transmit data on energy load and orientation. Once that mission is completed, the chipsats will fall out of orbit and burn up in Earth’s atmosphere. The launch is the second attempt to test the tiny devices; an earlier satellite launched in 2014 failed to deploy its cargo of chipsats before it disintegrated. Chipsat technology could prove useful for a number of scientific projects, such as determining the amount of drag created by small bits of debris in the upper atmosphere or mapping Earth’s magnetic field.

French president waives budget cuts for scientific research

1 June 2016
Science: After meeting with several Nobel laureates and a winner of the Fields Medal, French president François Hollande has agreed to cancel a €134 million proposed cut to the country’s research budget. The cut would have affected four major agencies: the National Center for Scientific Research, the National Institute for Agricultural Research, the National Institute for Computer Science and Applied Mathematics, and the Alternative Energies and Atomic Energy Commission. However, €122 million will still be trimmed from the budget, which will mostly affect higher education. Hollande also agreed to work toward increasing the funds available for research and higher education in the next annual budget.

Rwanda rebuilds its weather forecasting system after devastating civil war

1 June 2016
NPR: Detailed seasonal forecasts are critical for farmers in Rwanda, a hilly country where the weather varies by altitude. However, Rwanda's weather-tracking system was completely destroyed during the bloody civil war and genocide that erupted in 1994. The weather system had consisted of about 100 volunteers who recorded temperature and rainfall data from instruments at small outdoor observation stations. Over the 100-day conflict, many of the stations were destroyed and the volunteers who staffed them were killed. It took some 15 years to recruit new volunteers and reassemble the weather network. Then, to fill in the 15-year data gap, climate scientist Tufa Dinku of Columbia University created a substitute data record by estimating rainfall and temperature through the use of satellite imagery and computer models. The result is a weather-forecasting setup that may one day rival those of the rest of the world.

New number generator is more truly random

31 May 2016
Science News: Although physical phenomena such as coin tosses and dice rolls can generate random numbers, those methods are too slow for modern applications in such areas as statistics and cryptography. For those purposes, computational algorithms can create number sequences with random properties, but the numbers are not truly random because eventually the sequence will start repeating. Now a randomness extractor has been created that combines two independent sources of random numbers and discards any data that may be correlated or biased. The result is a more resilient system, even when very weak sources are used. The extractor should prove ideal for encrypting sensitive information and foiling would-be hackers.

Bumblebee hairs can sense floral electric fields

31 May 2016
Guardian: Besides using sight and smell to distinguish among flowers, bumblebees have the ability to detect the weak electrical fields produced by the plants. According to a new study, flying insects, such as bees, accumulate a tiny positive electric charge as they flit around, while flowers produce a weak negative charge. The difference in electric potential facilitates pollen transfer. To find out how bees' bodies respond to such an applied electric field, the researchers experimented with both live and dead bees. They found that although both the bees' antennae and body hairs were deflected by the electrical field, the body hairs were significantly more sensitive, reacting much faster and deflecting much farther. The researchers say that because many other insects have similar body hairs, they may also be sensitive to such small electric fields.

Press trumpets cell-phone cancer study

31 May 2016
Vox: A recent study linking cell-phone use to cancer set off alarms at several major news reporting agencies. Undertaken by the US National Toxicology Program, the study found that two types of cancerous tumor developed in rats exposed over a two-year period to the RF radiation emitted by cell phones. But several outside scientific experts, including one who deemed the study “interesting and well-designed,” and journalists such as Brad Plumer of Vox have urged the public to take a deep breath before buying into the hype the study has provoked. Plumer notes that it was just a single study, it was done on rats rather than on humans, and the rats were exposed to cell-phone radiation for far longer periods of time than any human would be. Moreover, cell phones have been in use for several decades already, yet cancer rates have not gone up. Plumer urges the press and the public to remain skeptical of any new study and to not jump to conclusions until more research has been done.

<em>Rosetta</em> spacecraft finds prebiotic chemicals on comet

31 May 2016
New Scientist: The simplest amino acid, glycine, has been found in the dust of comet 67P/Churyumov–Gerasimenko. Discovered by the Rosetta spacecraft, which has been orbiting the comet since 2014, the amino acid represents proof that comets delivered to Earth at least some of the ingredients for life. Furthermore, glycine was not the only prebiotic chemical the spacecraft found in the gas cloud surrounding the comet: Also detected were alcohols, sugars, oxygen compounds, and the scent of phosphorus, which is necessary for cellular processes. The prebiotic molecules probably form on comets when stellar radiation heats simpler chemicals; once formed, the molecules then get trapped in the comet’s icy surface. Rosetta continues to look for further evidence of life-forming ingredients, such as nucleotides.

Freeing Omid

27 May 2016
Extra Dimensions: Omid Kokabee, the physicist imprisoned in Iran, finally received some good news. Let’s keep sharing his story to help secure his release.

Obama becomes first sitting US president to visit Hiroshima

27 May 2016

The Guardian: On 26 May, President Obama became the first sitting US president to visit Hiroshima, Japan. Obama attended a ceremony at the bombing memorial, where he gave a speech about continuing efforts for nuclear disarmament and  nonproliferation. "Technological progress without an equivalent progress in human institutions can doom us," he said. "The scientific revolution that led to the splitting of an atom requires a moral revolution as well." Obama also met survivors of the attack, which killed 140 000 people.

Annual census shows US nuclear disarmament has slowed

27 May 2016

New York Times: Earlier this month, the US Department of Defense released its annual census of the nation's nuclear arsenal through the end of the 2015 fiscal year. At that point, the US possessed 4571 warheads, down 109 from the previous year and down 702 since 2008, the last year of President George W. Bush's term in office. The disarming of 109 warheads was the lowest annual rate of disarmament during President Obama's tenure, and the total reduction since 2008 accounted for just 13.3% of the stockpile, the smallest reduction by any administration since the end of the Cold War. According to Hans M. Kristensen of the Federation of American Scientists, the slower rate of disarmament is the result of various factors. Congress has opposed much of Obama's disarmament efforts, and Russia has rejected additional cuts beyond those agreed to in the 2010 New Start treaty. There is also a potential effect from the three-decade arsenal modernization effort that Obama initiated at an estimated cost of $1 trillion.

Congressional report calls for NASA to develop plan for interstellar mission

26 May 2016

Science: On Monday, the US House of Representatives appropriations committee presented its first draft of the 2017 budget. Accompanying the budget was a report from the committee subpanel that oversees NASA. In the report, the subpanel calls for NASA to produce a technology assessment and conceptual road map within a year for an interstellar probe capable of reaching 10% of the speed of light. The report comes in the wake of the Breakthrough Starshot project, which proposes to use concentrated laser light to send tiny probes to other stars. The report does not say where funding for the NASA project will come from.

Record-setting superconductor characterized

26 May 2016
Diffraction measurements have confirmed the predicted identity of the sulfur hydride’s superconducting phase.

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