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Van Allen belts accelerate their own particles rather than just trapping them. The two concentric rings of high-speed particles that encircle the Earth are finally giving up the secrets of their origin — 55 years after their discovery. Two NASA probes have found evidence that the Van Allen belts, as the rings are known, are responsible for accelerating the particles, rather than collecting energetic particles that originated elsewhere. Space scientists think that their latest findings1 could also account for the even more energetic belts circling Saturn and Jupiter, as well as high-energy radiation associated with worlds beyond the Solar System...

HOUSTON — Beyond the security gate at the Johnson Space Center’s 1960s-era campus here, inside a two-story glass and concrete building with winding corridors, there is a floating laboratory. Harold G. White, a physicist and advanced propulsion engineer at NASA, beckoned toward a table full of equipment there on a recent afternoon: a laser, a camera, some small mirrors, a ring made of ceramic capacitors and a few other objects. He and other NASA engineers have been designing and redesigning these instruments, with the goal of using them to slightly warp the trajectory of a photon, changing the distance it...

If a physics department has no women, does that mean there is hiring discrimination? Only if your job in sociology is to find discrimination. Simple statistics shows that is not true or there would be claims of discrimination in psychology, where lots of departments have no men. Yet when it comes to gender equality advocates, physics is always mentioned and psychology never is. A new analysis by the American Institute of Physics (AIP) Statistical Research Center debunks the claim that the existence of all-male departments is evidence of hiring bias. Labor statistics have backed that up; not only are women...

Enlarge Image Shining example. The GERDA experiment at the Gran Sasso lab in Italy has all but ruled out earlier claims for neutrinoless double-beta decay. Credit: The University of Tübingen A long-standing controversy among particle physicists looks to be settled—in the less exciting way—thanks to new data from an ultrasensitive particle detector deep underground. Physicists operating the GERmanium Detector Array (GERDA) 1400 meters down in Italy's Gran Sasso National Laboratory say that they see no signs of a hypothesized type of nuclear decay called neutrinoless double-beta decay that, were it conclusively observed, would almost certainly merit a Nobel Prize....

According to the First Law of Thermodynamics, nothing in the Universe (i.e., matter or energy) can pop into existence from nothing (see Miller, 2013). All of the scientific evidence points to that conclusion. So, the Universe could not have popped into existence before the alleged “big bang” (an event which we do not endorse). Therefore, God must have created the Universe. One of the popular rebuttals by the atheistic community is that quantum mechanics could have created the Universe. In 1905, Albert Einstein proposed the idea of mass-energy equivalence, resulting in the famous equation, E = mc2 (1905). We now...

ScienceDaily (Mar. 23, 2009) — Researchers are reporting compelling new scientific evidence for the existence of low-energy nuclear reactions (LENR), the process once called "cold fusion" that may promise a new source of energy.

Enlarge Mapping out the van der Waals interaction between two atoms. (a) In the experiment of Béguin et al. two atoms are trapped in the foci of two laser beams separated by a distance R. (b) Depending on R, the excitation laser field can couple the ground state |gg of the atomic pair to states containing one atom in the Rydberg state (|gr and |rg, respectively), or to a state with both atoms populating the Rydberg state |rr. The energy of the latter state is strongly shifted because of the van der Waals interaction UvdW between the atoms (see...

UK scientists want to redefine temperature using the Boltzmann constant, changing the way in which it has been calculated for over 50 years. The group, working at the UK’s National Physical Laboratory, published a study today that could make it possible to measure temperature much more accurately in the future.The current definition of temperature relies upon the triple point of water – the state at which water can be ice, liquid and vapour in equilibrium – but this makes accurate measurements of extreme temperatures difficult. The team say that the solution is to link the standard unit of temperature,...

The international definition of a second of time could be heading for a change, thanks to researchers who have demonstrated that an advanced type of ‘atomic clock’ has the degree of precision and stability needed to provide a new standard. Jérôme Lodewyck of the Paris Observatory and his colleagues have shown that two so-called optical lattice clocks (OLCs) can remain as perfectly in step as experimental precision can establish1. They say that this test of consistency is essential if OLCs are to be used to redefine the second, which is currently defined according to a different type of atomic clock....

Different-shaped beams could increase fibre-optic capacity, easing Internet congestion. Twisty beams of light could boost the traffic-carrying capacity of the Internet, effectively adding new levels to the information superhighway, suggests research published today in Science1. Internet traffic is growing exponentially and researchers have sought ways to squeeze ever more information into the fibre-optic cables that carry it. One successful method used over the last 20 years essentially added more traffic lanes, using different colours, or wavelengths, for different signals2. But to compensate for the added lanes, each one had to be made narrower. So, just as in a real highway,...

Two-photon microscopy: New research may help drastically reduce cost of powerful microscope technique Enlarge The same section of a mouse brain imaged with a femtosecond laser (above) and a much weaker laser but the new dye (below). (Phys.org) —A dye-based imaging technique known as two-photon microscopy can produce pictures of active neural structures in much finer detail than functional magnetic resonance imaging, or fMRI, but it requires powerful and expensive lasers. Now, a research team at the University of Pennsylvania has developed a new kind of dye that could reduce the cost of the technique by several orders of magnitude....

The effects of relativity can be seen in everyday phenomena © ShutterstockWhy is mercury a liquid at room temperature? If you ask that question in a school classroom you will probably be told that relativity affects the orbitals of heavy metals, contracting them and changing how they bond. However, the first evidence that this explanation is correct has only just been published.An international team led by Peter Schwerdtfeger of Massey University Auckland in New Zealand used quantum mechanics to make calculations of the heat capacity of the metal either including or excluding relativistic effects. They showed that if they...

Credit: Video courtesy of Cooper Downs Deep inside the sun's atmosphere, temperatures reach millions of degrees—so hot that even the best-shielded spacecraft can't go there (even at night). But natural objects that pass exceptionally close to the sun do provide scientists opportunities to directly probe the solar corona. Enter sun-grazing comets, such as comet Lovejoy, which whizzed within 140,000 kilometers of the sun's surface in mid-December 2011 (as seen in the first 20 seconds of the video). When a comet is far from the sun, its tail acts like a weather vane in the solar wind (the torrent of...

Technique that hides rapid data streams could provide ultra-secure communications. If you’ve ever wanted to edit an event from your history, then help may soon be at hand. Electrical engineers have used lasers to create a cloak that can hide communications in a 'time hole', so that it seems as if they were never sent. The method, published today in Nature1, is the first that can cloak data streams sent at the rapid rates typically seen in telecommunications systems. It opens the door to ultra-secure transmission schemes, and may also provide a way to better shield information from noise corruption....

The spectacular discovery of the Higgs boson in July 2012 confirmed a nearly 50-year-old theory of how elementary particles acquire mass, which enables them to form big structures such as galaxies and humans. “The fact that it was seen more or less where we expected to find it is a triumph for experiment, it’s a triumph for theory, and it’s an indication that physics works,” Arkani-Hamed told the crowd. However, in order for the Higgs boson to make sense with the mass (or equivalent energy) it was determined to have, the LHC needed to find a swarm of other particles,...

On galaxies and bosons, stars and quarks. In physics, truth does not always equal beauty. The Milky Way: An Insider’s Guide By William H. Waller (Princeton University Press, 296 pages, $29.95) A Palette of Particles By Jeremy Bernstein (Belknap Press of Harvard University, 224 pages, $18.95) THE BRITISH PHILOSOPHER J.L. Austin coined the handy phrase “medium-sized dry goods” to describe the world of everyday phenomena that the human nervous system is best suited to cope with, phenomena ranging in size from a grain of dust to a landscape. Within that range our senses and cognition are at home. All our...

Enlarge Left panel: Air molecules whiz around at a variety of speeds, and some are very fast. When they collide with both heavy and light elements - for example, xenon (purple) and silicon (orange) - these fast moving particles have enough momentum to affect both nuclei. Right panel: Dark matter particles are moving more slowly and are less able to affect the heavy xenon nucleus. As a result, detectors made from lighter materials like silicon may prove to be more effective at picking up signals of dark matter. Credit: Greg Stewart/SLAC National Accelerator Laboratory (Phys.org) —Now that it looks...

Credit: Phys. Rev. Lett. 110, 211302 (2013) (Phys.org) —A team of Harvard University physicists has proposed the possible existence of a type of dark matter not described by current physics models. In their paper published in the journal Physical Review Letters, the team suggests it's possible that not all dark matter is cold and collision-less. In the visible universe, galaxies form into a disk shape—the Milky Way is a good example. All of its members align roughly along a single plane, this due to the forces of gravity and spin. Objects form into masses which, over time, spread out...

Most people have heard of “evolutionary biology.” But the term “evolution” is often applied in a broader sense (gradual, naturalistic changes over long ages) to other fields of study. Some people study geology or astronomy from an evolutionary perspective. But has anyone ever studied “evolutionary mathematics”? What would an evolutionist mathematician study? Can the existence of numbers and mathematical laws be explained by a time-and-chance naturalistic origin? To answer these questions, let us first consider some background material and definitions. Mathematics is the study of the relationships and properties of numbers. What, then, are numbers? That may seem like an...

A modification to one of the most fundamental laws of physics may provide a link to the rise of intelligence, cooperation - even upright walking. The idea of entropy describes the way in which the Universe heads inexorably toward a higher state of disorder. A mathematical model in Physical Review Letters proposes that systems maximise entropy in the present and the future. Simple simulations based on the idea reproduce a variety of real-world cases that reflect intelligent behaviour. The idea of entropy is fundamentally an intuitive one - that the Universe tends in general to a more disordered state. But...