As physicists gather in early August to celebrate a century since the initial discovery of cosmic rays, Alan Watson, emeritus professor of physics at the University of Leeds, explains how physicists have gradually revealed the nature of these mysterious objects and examines the progress being made in understanding where they come from.
Earth
A team of researchers from the Wildlife Conservation Society (WCS) and the National Research Council of Argentina recently fitted a South American sea bird called an imperial cormorant with a small camera, then watched stunned as it became "superbird" – diving 150 feet underwater in 40 seconds, feeding on the ocean floor for 80 seconds where it eventually caught a snakelike fish, before returning to the surface 40 seconds later.
Scientists at the University of Liverpool have discovered that variations in the long-term reversal rate of the Earth's magnetic field may be caused by changes in heat flow from the Earth's core into the base of the overlying mantle.
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University of British Columbia and Harvard researchers have provided visual evidence that atmospheric particles--which are ubiquitous in the atmosphere, especially above densely populated areas--separate into distinct chemical compositions during their life cycle.
A mathematical physicist and her colleague, both from the Free University of Bozen-Bolzano, Italy, are about to publish a study in EPJ B¹ on a family of taxation and wealth redistribution models. The findings could lead to numerical simulations of potential wealth distribution scenarios playing out over the long term and could be used for policy decision making.
Mathematicians at the Institute for Advanced Study in New Jersey "bridged" topology and fractals and made a discovery that could lead to a new way of describing extremely complicated shapes such as the configuration of the tiniest defects in a metal or even the froth of a breaking wave.
Inspired by the water-repellent properties of the lotus leaf, a group of scientists in China has discovered a way to impart a fog-free, self-cleaning finish to glass and other transparent materials. "Superhydrophobic" surfaces, such as the lotus leaf, are excellent at repelling water and also boast other "smart" self-cleaning, anti-glare, anti-icing, and anti-corrosion properties. By using hollow silica nanoparticles that resemble raspberries, scientists at the Chinese Academy of Sciences were able to apply a clear, slick, water-repellent surface to glass.
The destruction of atmospheric ozone can take place within newly forming Polar Stratospheric Clouds (PSCs), which serve as the battleground for manmade chlorofluorocarbons (CFCs) to attack and destroy ozone. These clouds form when clusters of frozen water "pick up" other atmospheric molecules such as methane, nitrogen oxides, and water molecules, similar to the way a snowball's girth increases as it rolls down a mountainside.
After the fall of the Soviet Union twenty years ago, water distribution in Central Asia became a source of conflict. In areas where summer precipitation is low, glaciers play an important role when considering the quantity of available water. The Tien Shan region is a prime example; mountain glaciers in this region contribute significantly to the fresh water supply in the arid zones of Kyrgyzstan, Kazakhstan, Uzbekistan, Turkmenistan, and Northwestern China. Like Switzerland, Kyrgyzstan serves as a water tower for its neighboring countries.
Sandwiching individual graphene sheets between insulating layers in order to produce electrical devices with unique new properties, the method could open up a new dimension of physics research.
Writing in Nature Materials, the scientists show that a new side-view imaging technique can be used to visualize the individual atomic layers of graphene within the devices they have built. They found that the structures were almost perfect even when more than 10 different layers were used to build the stack.
On a time scale of tens to hundreds of millions of years, the geomagnetic field may be influenced by currents in the mantle. The frequent polarity reversals of Earth's magnetic field can also be connected with processes in the mantle. These are the research results presented by a group of geoscientists in the new advance edition of "Nature Geoscience" on Sunday, July 29th.
CORVALLIS, Ore. – The chronic drought that hit western North America from 2000 to 2004 left dying forests and depleted river basins in its wake and was the strongest in 800 years, scientists have concluded, but they say those conditions will become the "new normal" for most of the coming century.
Such climatic extremes have increased as a result of global warming, a group of 10 researchers reported today in Nature Geoscience. And as bad as conditions were during the 2000-04 drought, they may eventually be seen as the good old days.
Debate over the origin of large-scale polygons (hundreds of meters to kilometers in diameter) on Mars remains active even after several decades of detailed observations. Similarity in geometric patterns on Mars and Earth has long captured the imagination. In this new article from GSA Today, geologists at The University of Texas at Austin examine these large-scale polygons and compare them to similar features on Earth's seafloor, which they believe may have formed via similar processes.
Phase transitions between different states of matter can be associated with a specific type of excitation called the "Higgs excitation". This phenomenon has now been observed in a two-dimensional quantum gas at temperatures near absolute zero.
In physics, spontaneous symmetry breaking is a fundamental feature of transitions between different states of matter. An example of this phenomenon is the abrupt alignment of spin orientation in a ferromagnetic substance when the material is cooled below the so-called Curie temperature.