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(Phys.org) —When a molten material cools quickly, parts of it may have enough time to grow into orderly crystals. But if the cooling rate is too fast for the entire melt to crystallize, the remaining material ends up in a non-crystalline state known as a glass, with atoms caught in place essentially as a frozen liquid. Recently, a group of researchers at the National Institute of Standards and Technology (NIST) came across an unexpected reversal of this usual sequence of events. After cooling a molten alloy of aluminum, iron, and silicon, they found that glassy nodules of a non-crystalline solid...

It creeps in slowly in the dark of night, and once inside, it almost never goes away. It's known as the Hum, a steady, droning sound that's heard in places as disparate as Taos, N.M.; Bristol, England; and Largs, Scotland. But what causes the Hum, and why it only affects a small percentage of the population in certain areas, remain a mystery, despite a number of scientific investigations...

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...

Neutrinos come in three flavors — electron, muon and tau — and have been known to change, or oscillate, between certain flavors. Now, for the first time, scientists can definitively say they've discovered muon neutrinos changing into electron neutrinos.

Exotic particles called neutrinos have been caught in the act of shape-shifting, switching from one flavor to another, in a discovery that could help solve the mystery of antimatter. Neutrinos come in three flavors — electron, muon and tau — and have been known to change, or oscillate, between certain flavors. Now, for the first time, scientists can definitively say they've discovered muon neutrinos changing into electron neutrinos. The discovery was made at the T2K neutrino experiment in Japan, where scientists sent a beam of muon neutrinos from the J-PARC laboratory in Tokai Village on the eastern coast of Japan,...

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....

What is rarer than a shooting star? Rarer than a diamond? Rarer than any metal, any mineral, so rare that if you scan the entire earth, all six million billion billion kilos or 13,000,000,000,000,000,000,000,000 pounds of our planet, you would find only one ounce of it? What is so rare it has never been seen directly, because if you could get enough of it together, it would self-vaporize from its own radioactive heat? What is this stuff that can't be seen or found? Well, here's a hint. It's sitting modestly in a lower row in the Periodic Table, down on...

Sharp corners and jagged edges on graphene sheets enable them to puncture cell membranes. Researchers from Brown University have shown how tiny graphene microsheets — ultra-thin materials with a number of commercial applications — could be big trouble for human cells. The research shows that sharp corners and jagged protrusions along the edges of graphene sheets can easily pierce cell membranes. After the membrane is pierced, an entire graphene sheet can be pulled inside the cell where it may disrupt normal function. The new insight may be helpful in finding ways to minimize the potential toxicity of graphene, said...

A black hole is created when a huge star runs out of fuel for nuclear fusion and collapses under its own gravity. The star's outer layers are expelled, and its core falls in on itself, with the pull of gravity becoming ever stronger, until what's left is the core's mass condensed into an extremely small area. According to general relativity, this area is a single point of space-time, and the density there is infinitely large — a singularity. But most scientists think singularities don't really exist, that they're just a sign that equations have broken down and fail to adequately...

Courtesy of Kirk Zamieroski, American Chemical Society WASHINGTON — The pursuit that obsessed some of the world's greatest geniuses for centuries — alchemy and its quest for the “Philosopher’s Stone” that would transform lead and other base metals into gold — is the topic of a new episode in the American Chemical Society Bytesize Science video series. The video, from the world’s largest scientific society, is at www.BytesizeScience.com. It features Laurence Principe, Ph.D., a noted historian of science and expert on alchemy, which, far from being solely a misguided pseudoscience, helped set the stage for the emergence of modern science....

If each energy field pervading space is thought of as the surface of a pond, and waves and particles are the turbulence on that surface, then the new evidence strengthens the argument that a vibrant, hidden world lies beneath. For decades, the surface-level description of the subatomic world has been sufficient to make accurate calculations about most physical phenomena. But recently, a strange class of matter that defies description by known quantum mechanical methods has drawn physicists into the depths below... Of all the strange forms of matter, cuprates -- copper-containing metals that exhibit a property called high-temperature superconductivity...

'As if millions of voices suddenly cried out in terror and were suddenly silenced' A pair of European astrophysicists believe they've solved the mystery of exceedingly bright, never-repeated flashes of radio waves that come to us from the distant past. The source of those brief, intense flashes can be defined in two ways, depending upon whether you'd prefer to look at the event as a death or a birth. "We suggest that a fast radio burst represents the final signal of a supramassive rotating neutron star that collapses to a black hole due to magnetic braking," write Heino Falcke of...

It’s a recurring theme in astronomy: observers see a blast of energy out in the cosmos, scratch their heads in confusion for a while, and finally uncover the existence of something entirely surprising and new. It happened with the quasars (now known to be gigantic burps from black holes swallowing hot gas), the pulsars (fast-spinning neutron stars sending out blips of radio noise hundreds of times every second), and even the Big Bang itself, first seen as a stream of microwaves slamming into Earth from all directions, nearly 14 billion years after the event itself.Now it may be happening again....

Just as sailors once used the stars to navigate the sea, space travelers may be able to use the stars to navigate the solar system. Except that this time, the stars we’d use will be dead ones. A specific class of neutron stars known as pulsars, defined by the repeated pulses of radiation they emit. The trick, according to a recent paper, may be to use pulsars as a form of interplanetary – and possibly even interstellar – GPS. Theories and ideas on spacecraft engines are plentiful. Foundations such as Icarus Interstellar keenly advocate the development of new propulsion systems,...

Last week, in Nice, France, I was privileged to participate, along with 30 scholars, mostly scientists and mathematicians, in a conference on the question of whether the universe was designed, or at least fine-tuned, to make life, especially intelligent life. Participants — from Yale, Princeton, Harvard, Berkeley and Columbia among other American and European universities — included believers in G0D, agonistics and atheists.

Title:NASA Finds Black Hole Cluster No matter how old you are, space never stops being cool. That applies doubly to black holes, which is why NASA's latest discovery should be considered totally awesome: using the Chandra X-ray observatory, the agency found an "unprecedented" cluster of black holes in the Andromeda galaxy. How unprecedented? There could be 26 of them in this cluster alone. And these were just the ones that were immediately identifiable, as scientists say there are likely many more that are currently invisible. Said the lead author of the study, "We think it's just the tip of the...

One physicist says he likes this theory because of “its simplicity, uniqueness and the fact that it can be tested.”Theoretical physicists at Vanderbilt University contend that a simply theory may explain mysterious dark matter. They propose that most of the matter in the universe may be constructed of particles that have an abnormal, donut-shaped electromagnetic field known as an anapole. According to a news release from Vanderbilt University, Professor Robert Scherrer and post-doctoral fellow Chiu Man Ho carried out an in-depth analysis to determine the validity of this theory. Scherrer points out that he likes this theory because of “its...

'Superatoms' can be used to make ionic-esque lattices using C60 (black) and metal chalcogenides © Science/AAASCould a new periodic table be on the horizon, populated not by conventional elements but by new ‘superatoms’ designed in the lab? This is the intriguing implication of new work by US chemists, who have made structural analogues of simple ionic compounds such as sodium chloride and cadmium iodide by interacting large molecular clusters instead of individual atoms.The new compounds have unexpected electronic and magnetic properties, opening the prospect for the design of bespoke solid state materials whose properties can be tuned by the...

New Science of Cosmography Reveals 3-D Map of the Local Universe The three-dimensional structure of the local universe may one day become as familiar as our local geography thanks to a new generation of maps that reveal our neighbourhood’s rich complexity and our place within it  The geography of our world is one of the great cultural invariants. There can hardly be the person on the planet who isn’t familiar with the shape of the continents and how they dovetail together or of the Earth is a pale blue sphere orbiting the Sun with seven other planets.Given a three-dimensional model...

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,...