General Physics Thread

Molecule-making machine simplifies complex chemistry: "A new molecule-making machine could do for chemistry what 3-D printing did for engineering: Make it fast, flexible and accessible to anyone. Chemists built the machine to assemble complex small molecules at the click of a mouse, like a 3-D printer at the molecular level. The automated process has the potential to greatly speed up and enable new drug development and other technologies that rely on small molecules."

Materials theory combines strength, stiffness and toughness of composites into a single design map: "Mother-of-pearl, the iridescent layer in the shells of some mollusks, inspired a Rice University study that will help scientists and engineers judge the ultimate strength, stiffness and toughness of composite materials for anything from nanoscale electronics to buildings."

Nano piano's lullaby could mean storage breakthrough: "Researchers have demonstrated the first-ever recording of optically encoded audio onto a non-magnetic plasmonic nanostructure, opening the door to multiple uses in informational processing and archival storage."

Second natural quasicrystal found in 4.5-billion-year-old meteorite: "A team from Princeton University and the University of Florence in Italy has discovered a quasicrystal—so named because of its unorthodox arrangement of atoms—in a 4.5-billion-year-old meteorite from a remote region of northeastern Russia, bringing to two the number of natural quasicrystals ever discovered. Prior to the team finding the first natural quasicrystal in 2009, researchers thought that the structures were too fragile and energetically unstable to be formed by natural processes."

Magnetised graphene could see a 'million-fold' increase in hard drive storage: "Scientists in the US have figured out how to magnetise large areas of graphene, which they say could revolutionise our current technique for storing data.

Graphene the wonder-material has got some pretty strange properties, but one of the most unexpected is magnetism. Over the past 10 years, researchers have been intensely investigating the various characteristics of this multi-purpose material - made from multiple stacks of 1-atom-thick carbon layers - and have only been able to explain its occasional magnetism though manufacturing defects or through the binding of certain chemical groups that give it this property.

But making graphene reliably electromagnetic - and therefore usefully electromagnetic - has proven difficult. Until now, because a team from the US Naval Research Laboratory have just figured out how to achieve what they’re calling 'a simple and robust means to magnetise graphene' over a large array of the material, and they do it using plain old hydrogen."

Data structures influence speed of quantum search in unexpected ways: "Using the quantum property of superposition, quantum computers will be able to find target items within large piles of data far faster than conventional computers ever could. But the speed of the search will likely depend on the structure of the data.

Such a search would proceed as a quantum particle jumps from one node of a connected set of data to another. Intuition says that the search would be fastest in a highly connected database."

Scientists invent new way to control light, critical for next gen of super fast computing: "A device resembling a plastic honeycomb yet infinitely smaller than a bee's stinger can steer light beams around tighter curves than ever before possible, while keeping the integrity and intensity of the beam intact.

The work, conducted by researchers at the University of Texas El Paso (UTEP) and at the University of Central Florida (UCF) and published in the journal Optics Express, introduces a more effective way to transmit data rapidly on electronic circuit boards by using light."

Scientists watch quantum dots 'breathe' in response to stress: "Researchers at the Department of Energy's SLAC National Accelerator Laboratory watched nanoscale semiconductor crystals expand and shrink in response to powerful pulses of laser light. This ultrafast "breathing" provides new insight about how such tiny structures change shape as they start to melt – information that can help guide researchers in tailoring their use for a range of applications."

New transitory form of silica observed: "A Carnegie-led team was able to discover five new forms of silica under extreme pressures at room temperature. Their findings are published by Nature Communications."

Squid-inspired 'invisibility stickers' could help soldiers evade detection in the dark: "Squid are the ultimate camouflage artists, blending almost flawlessly with their backgrounds so that unsuspecting prey can't detect them. Using a protein that's key to this process, scientists have designed "invisibility stickers" that could one day help soldiers disguise themselves, even when sought by enemies with tough-to-fool infrared cameras."

Landmark study proves that magnets can control heat and sound: "Researchers at The Ohio State University have discovered how to control heat with a magnetic field.

In the March 23 issue of the journal Nature Materials, they describe how a magnetic field roughly the size of a medical MRI reduced the amount of heat flowing through a semiconductor by 12 percent.

The study is the first ever to prove that acoustic phonons—the elemental particles that transmit both heat and sound—have magnetic properties."

Scientists build a nanolaser using a single atomic sheet: "Scientists have built a new nanometer-sized laser using a semiconductor that's only three atoms thick. It could help open the door to next-generation computing that uses light, rather than electrons, to transfer information."

Quantum experiment verifies Einstein's 'spooky action at a distance': "In a paper published in the journal Nature Communications, CQD Director Professor Howard Wiseman and his experimental collaborators at the University of Tokyo report their use of homodyne measurements to show what Einstein did not believe to be real, namely the non-local collapse of a particle's wave function."

Group creates light-emitting electrochemical cell for use in textiles: "A large team of researchers in China has developed a type of light emitting electrochemical cell (LEC) that can be woven into fabric material. As the team notes in their paper published in the journal Nature Photonics, their cells can be used to create wearable electronics. Henk Bolink and Enrique Ortí with the University of Valencia in Spain, offer a News & Views piece on the work done by the team in the same journal issue."

New form of ice: Square ice filling for a graphene sandwich: "Water exists in myriad forms, and for poets and scientists alike this structurally simple yet at the same time behaviourally complex molecule never fails to fascinate. In our everyday lives we are familiar with water in its more common liquid, ice and vapour forms. Scientists also study water under more extreme conditions, including at high pressures, where it can exist in the solid state even at room temperature."

3,000 atoms entangled with a single photon: "Physicists from MIT and the University of Belgrade have developed a new technique that can successfully entangle 3,000 atoms using only a single photon. The results, published today in the journal Nature, represent the largest number of particles that have ever been mutually entangled experimentally.

The researchers say the technique provides a realistic method to generate large ensembles of entangled atoms, which are key components for realizing more-precise atomic clocks."

Study demonstrates desalination with nanoporous graphene membrane: "Less than 1 percent of Earth's water is drinkable. Removing salt and other minerals from our biggest available source of water—seawater—may help satisfy a growing global population thirsty for fresh water for drinking, farming, transportation, heating, cooling and industry. But desalination is an energy-intensive process, which concerns those wanting to expand its application.

Now, a team of experimentalists led by the Department of Energy's Oak Ridge National Laboratory has demonstrated an energy-efficient desalination technology that uses a porous membrane made of strong, slim graphene—a carbon honeycomb one atom thick. The results are published in the March 23 advance online issue of Nature Nanotechnology."

Engineering students use sound waves to put out fires: "Two engineering students at George Mason University have found a way to use sound waves to quash fires and have built a type of extinguisher using what they have learned that they hope will revolutionize fire fighting technology. Viet Tran a computer engineering major and Seth Robertson, an electrical engineering major, chose to investigate the possibility of using sound to put out fires as a senior research project and now believe they have found something that might really work.

Prior research has shown that sound waves can impact fires, and other researchers, such as those working for DARPA a couple of years ago, even investigated the possibility of using sound to put out fires, but thus far, no sound based extinguishers have been built and sold as a means to stop fires. The research by the duo at GMU might change that."

Theory of the strong interaction verified: Supercomputer calculates mass difference between neutron and proton: "The fact that the neutron is slightly more massive than the proton is the reason why atomic nuclei have exactly those properties that make our world and ultimately our existence possible. Eighty years after the discovery of the neutron, a team of physicists has finally calculated the tiny neutron-proton mass difference. The findings are considered a milestone by many physicists and confirm the theory of the strong interaction."

Chemists make new silicon-based nanomaterials: "A new process uses silicon telluride to produce multilayered two-dimensional semiconductor materials in a variety of shapes and orientations."

Using magnetic fields to understand high-temperature superconductivity: "Taking our understanding of quantum matter to new levels, scientists at Los Alamos National Laboratory are exposing high-temperature superconductors to very high magnetic fields, changing the temperature at which the materials become perfectly conducting and revealing unique properties of these substances."

edited 27th Mar '15 12:19:46 AM by rmctagg09

A necklace fit for a virus

Researchers use Mira to peer inside high-temperature superconductors: "Researchers from the University of Illinois at Urbana-Champaign (UIUC) are using supercomputing resources at the Argonne Leadership Computing Facility (ALCF), a DOE Office of Science User Facility, to shed light on the mysterious nature of high-temperature superconductors.

With critical temperatures ranging from 30 Kelvin to 130 Kelvin (405 degrees below zero to 225 degrees below zero Fahrenheit), this relatively new class of superconductors is high-temperature in name only. Prior to their discovery in 1986, it was widely believed that superconductivity—a material's ability to transmit electric current with no resistance—could only occur below temperatures of 30 Kelvin.

The discovery of high-temperature superconductors led to countless follow-on research efforts and the identification of several other high-temperature superconductors, but the origin of the materials' unique properties remains elusive."

Boeing has patented a plasma ‘force field’ to protect against shock waves: "As weapons get more sophisticated, researchers are trying to build defence systems that can keep pace, and what’s better than a force field?

Aerospace and defence giant Boeing has been awarded a patent to develop a force field-like system that could protect military vehicles from shockwaves following explosions from missiles or improvised explosive devices.

Boeing’s proposed system involves using a combination of lasers, electricity and microwaves to rapidly heat up the air between the vehicle and a blast. This heat creates a plasma shield that's denser than the surrounding air and able to deflect or absorb the energy from the incoming shockwave."

Photon 'afterglow' could transmit information without transmitting energy: "Physicists have theoretically shown that it is possible to transmit information from one location to another without transmitting energy. Instead of using real photons, which always carry energy, the technique uses a small, newly predicted quantum afterglow of virtual photons that do not need to carry energy. Although no energy is transmitted, the receiver must provide the energy needed to detect the incoming signal—similar to the way that an individual must pay to receive a collect call."

Drop the bounce test: A common battery test often bounces off target: "The battery bounce test, popularized in online videos, has led to the common conclusion that a high bounce means a dead battery. But researchers have found that bouncing is not actually an effective way to check a battery's charge."

Scientists develop perfume which smells better the more you sweat: "The first-ever perfume delivery system to ensure the more a person sweats, the better they will smell, has been developed by scientists at Queen's University Belfast.

Researchers in the Queen's University Ionic Liquid Laboratories (QUILL) Research Centre have developed a unique new perfume delivery system which releases more of its aroma when it comes into contact with moisture, meaning a person smells nicer when their sweat levels increase."

Scientists synthesize molecules that absorb any color of sunlight, from the oranges through the near-infrared: "In 2005, scientists studying tiny sac-like creatures called sea squirts found bacteria containing two types of chlorophyll (a and b) in cavities inside the squirts' tissues. These two pigments were soaking up most of the sunlight—the violets, indigos, blues, green, yellows and oranges.

All that filtered through the squirts was deep red light. So the scientists were surprised to discover a film of photosynthesizing microbes on the underside of the squirts as well. They turned out to be full of chlorophyll d, a rare variant of the chlorophyll molecule that absorbs near-infrared light.

By tinkering with the chlorophyll molecule, evolution had managed to contrive a version that soaks up the last bit of sunlight, adapting the bacteria to life in perpetual shade.

It is an astonishing feat, but one achieved by nature's traditional method of trial and error. A team of three chemists who study pigments like chlorophyll aspire to a different level of mastery, understanding how the pigments work from first principles and well enough to manipulate their light absorption at will."

Frustrated magnets: New experiment reveals clues to their discontent: "An experiment conducted by Princeton researchers has revealed an unlikely behavior in a class of materials called frustrated magnets, addressing a long-debated question about the nature of these discontented quantum materials.

The work represents a surprising discovery that down the road may suggest new research directions for advanced electronics. Published this week in the journal Science, the study also someday may help clarify the mechanism of high-temperature superconductivity, the frictionless transmission of electricity."

Super-efficient graphene lightbulbs will hit markets this year: "A lightbulb made from wonder-material graphene will reportedly go on sale later this year, and it's promising to be brighter, cheaper, longer-lasting and use 10 percent less energy than even the best LEDs.

The dimmable lightbulb contains a filament-shaped LED that's coated in graphene, a one-atom-thick material that's 200 times stronger than steel, super flexible and also extremely conductive. If all goes to plan, this will be the first commercial graphene product to hit the market."

edited 4th Apr '15 12:19:08 AM by rmctagg09

Physicists first to create new molecule with record-setting dipole moment: "A proposed pathway to construct quantum computers may be the outcome of research by a University of Oklahoma physics team that has created a new molecule based on the interaction between a highly-excited type of atom known as a Rydberg atom and a ground-state atom. A unique property of the molecule is the large permanent dipole moment, which reacts with an electric field much like a bar magnet reacts with a magnetic field."

This yarn conducts electricity: "Right now, wearable fitness trackers and bionic devices like electronic skin look cool, but they’re a bit clunky. One reason is that rigid wires tend to lose their conductivity after being bent, limiting the range of flexibility for wearables. Now, researchers report the creation of an ultrathin, fabric circuit that keeps high conductivity even while bending and stretching as much as yoga pants."

In terms of physics announcements, recently at 10:41 AM (Not sure which timezone) today the Large Hadron Collider has been restarted.

At first at a low energy setting to check that the systems work, before boosting it up.

Source.

Researchers use 'soft' nanoparticles to model behavior at interfaces: "Where water and oil meet, a two-dimensional world exists. This interface presents a potentially useful set of properties for chemists and engineers, but getting anything more complex than a soap molecule to stay there and behave predictably remains a challenge.

A University of Pennsylvania team has now shown how to make nanoparticles that are attracted to this interface but not to each other, creating a system that acts as a two-dimensional liquid. By measuring this liquid's pressure and density, they have shown a way forward in using it for a variety of applications, such as in nanomanufacturing, catalysis and photonic devices."

Magnetic-field detector is 1,000 times more efficient than its predecessors: "MIT researchers have developed a new, ultrasensitive magnetic-field detector that is 1,000 times more energy-efficient than its predecessors. It could lead to miniaturized, battery-powered devices for medical and materials imaging, contraband detection, and even geological exploration."

'Phonon tunneling' explains heat flow across nanometer-wide gaps, study finds: "Conduction and thermal radiation are two ways in which heat is transferred from one object to another: Conduction is the process by which heat flows between objects in physical contact, such as a pot of tea on a hot stove, while thermal radiation describes heat flow across large distances, such as heat emitted by the sun.

These two fundamental heat-transfer processes explain how energy moves across microscopic and macroscopic distances. But it's been difficult for researchers to ascertain how heat flows across intermediate gaps.

Now researchers at MIT, the University of Oklahoma, and Rutgers University have developed a model that explains how heat flows between objects separated by gaps of less than a nanometer. The team has developed a unified framework that calculates heat transport at finite gaps, and has shown that heat flow at sub-nanometer distances occurs not via radiation or conduction, but through 'phonon tunneling.'"

Inkjet-printed liquid metal could bring wearable tech, soft robotics: "New research shows how inkjet-printing technology can be used to mass-produce electronic circuits made of liquid-metal alloys for 'soft robots' and flexible electronics."

New understanding of electromagnetism could enable 'antennas on a chip': "A team of researchers from the University of Cambridge have unravelled one of the mysteries of electromagnetism, which could enable the design of antennas small enough to be integrated into an electronic chip. These ultra-small antennas - the so-called 'last frontier' of semiconductor design - would be a massive leap forward for wireless communications.

In new results published in the journal Physical Review Letters, the researchers have proposed that electromagnetic waves are generated not only from the acceleration of electrons, but also from a phenomenon known as symmetry breaking. In addition to the implications for wireless communications, the discovery could help identify the points where theories of classical electromagnetism and quantum mechanics overlap."

Quantum interference links the fate of two atoms: "For the first time, physicists have achieved interference between two separate atoms: when sent towards the opposite sides of a semi-transparent mirror, the two atoms always emerge together. This type of experiment, which was carried out with photons around thirty years ago, had so far been impossible to perform with matter, due to the extreme difficulty of creating and manipulating pairs of indistinguishable atoms."

Measurement of first ionization potential of lawrencium reignites debate over periodic table: "A team of researchers with member affiliations from across the globe has succeeded in conducting a measurement of the first ionization potential of lawrencium. In their paper published in the journal Nature, the team describes how they achieved the feat and what they believe it means for placement on the Periodic Table of Elements. Andreas Türler of the University of Bern offers a News & Views perspective piece on the work done by the team in the same issue.

Lawrencium is an element that does not exist in nature, scientists create it in the lab and use it for study, though the process is difficult and the result lasts for only a few seconds. In this new effort, the researchers used a known technique to create the element, then devised a way to measure its first ionization potential—which describes the amount of energy required to cause one atom of it to be turned into an ion by knocking off one of its electrons. It is this measurement that forms the basis of element placement on the periodic table.

To make this measurement for lawrencium (named for Ernest Lawrence), the team created some samples by shooting boron atoms at a bit of californium—doing so caused a few atoms of a lawrencium isotope to come into existence. Those atoms were then captured using a cadmium mist iodide and placed on a piece of metal which was then heated to 2,700 kelvin—hot enough to knock electrons off of some of the atoms. After that, all it took was summing the atoms that were ionized and calculating the energy it took to make it happen. Doing so revealed that it took just 4.96 electronvolts to ionize one of the atoms, an unexpectedly small amount, which likely means that lawrencium's outermost electron is very loosely bound, which means, that placing the element where it has been put on the periodic table up till now, might not work."

Physicists show 'quantum freezing phenomenon' is universal: "Physicists who work on quantum technologies are always looking for ways to manage decoherence, which occurs when a quantum system unavoidably interacts with the surrounding environment. In the past few years, scientists have discovered that some quantum correlations can be "frozen" in a constant state and remain that way in the presence of noise, potentially offering a protective mechanism against decoherence. So far, however, quantum freezing has been shown to exist only on a case-by-case basis and under certain conditions, and its potential protective effect has not been fully exploited.

Now in a new paper to be published in Nature Scientific Reports, physicists Marco Cianciaruso, Thomas Bromley, Wojciech Roga, Rosario Lo Franco, and Gerardo Adesso have shown that the freezing of quantum correlations is universal—that is, it is independent of the method used for measuring the correlations. While working on this proof, the scientists also found that it may be possible to not just prevent but also reverse the effects of decoherence under certain circumstances, which they show by demonstrating the existence of an intriguing new phenomenon modelled by a global rephasing channel."

For ultra-cold neutrino experiment, a successful demonstration: "Today an international team of nuclear physicists announced the first scientific results from the Cryogenic Underground Observatory for Rare Events (CUORE) experiment. CUORE, located at the INFN Gran Sasso National Laboratories in Italy, is designed to confirm the existence of the Majorana neutrino, which scientists believe could hold the key to why there is an abundance of matter over antimatter. Or put another way: why we exist in this universe."

Will we ever have a theory of everything?

edited 9th Apr '15 3:18:44 PM by rmctagg09