General Physics Thread

This might be an old one, but there's evidence to suggest that the universe is a giant hologram, basically a 2-D image that we percieve as 3D.

Basically, Real Life runs on Id Tech 1.

Channeling valleytronics in graphene: "Scientists have discovered topologically protected 1-D electron conducting channels at the domain walls of bilayer graphene that should prove useful for valleytronics."

Electrons corralled using new quantum tool: "Researchers have succeeded in creating a new 'whispering gallery' effect for electrons in a sheet of graphene — making it possible to precisely control a region that reflects electrons within the material. They say the accomplishment could provide a basic building block for new kinds of electronic lenses, as well as quantum-based devices that combine electronics and optics."

A metal composite that will (literally) float your boat: "Researchers have demonstrated a new metal matrix composite that is so light that it can float on water. A boat made of such composites will not sink despite damage to its structure. This first lightweight syntactic foam also holds promise for automotive fuel economy because of its heat resistance. The magnesium alloy matrix composite is reinforced with silicon carbide hollow particles and is strong enough to withstand rigorous conditions faced in the marine environment."

Scientists have discovered a new state of matter, called 'Jahn-Teller metals': "An international team of scientists has announced the discovery of a new state of matter in a material that appears to be an insulator, superconductor, metal and magnet all rolled into one, saying that it could lead to the development of more effective high-temperature superconductors.

Why is this so exciting? Well, if these properties are confirmed, this new state of matter will allow scientists to better understand why some materials have the potential to achieve superconductivity at a relativity high critical temperature (Tc) - 'high' as in −135 °C as opposed to −243.2 °C. Because superconductivity allows a material to conduct electricity without resistance, which means no heat, sound, or any other form of energy release, achieving this would revolutionise how we use and produce energy, but it’s only feasible if we can achieve it at so-called high temperatures."

Large Hadron Collider: Rare Subatomic Process: "Two experiments at the Large Hadron Collider at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, have combined their results and observed a previously unseen subatomic process."

Physicists Observe Attosecond Real-Time Restructuring of Electron Cloud in Molecule: "The recombination of electron shells in molecules, taking just a few dozen attoseconds (a billionth of a billionth of a second) can now be viewed 'live,' thanks to a new method."

Three-decade quest backs physics' 'Standard Model': "Scientists on Wednesday said that after a nearly three-decade bid they had detected a telltale change in a sub-atomic particle, further backing a key theory about the Universe.

Researchers at the world's biggest particle collider said they had observed an extremely rare event—the decay of the neutral B meson into a pair of muons, the heavy cousins of electrons.

The results provide further support for the so-called Standard Model, the conceptual framework for the particles and forces that constitute the cosmos, they said in the journal Nature."

Scientists develop atomic-scale hardware to implement natural computing: "Despite the many great achievements of computers, no man-made computer can learn from its environment, adapt to its surroundings, spontaneously self-organize, and solve complex problems that require these abilities as well as a biological brain. These abilities arise from the fact that the brain is a complex system capable of emergent behavior, meaning that the system involves interactions between many units resulting in macroscale behavior that cannot be attributed to any individual unit.

Unfortunately, conventional fabrication methods used for today's computers cannot be used to realize complex systems to their full potential due to scaling limits—the methods simply cannot make small enough interconnected units.

Now in a new paper published in Nanotechnology, researchers at UCLA and the National Institute for Materials Science in Japan have developed a method to fabricate a self-organized complex device called an atomic switch network that is in many ways similar to a brain or other natural or cognitive computing device."

Antimatter haze found in thundercloud, and the laws of physics can’t explain it: "Six years ago, atmospheric physicist, Joseph Dwyer, accidentally flew his plane into a thundercloud, and right through an unexpected pocket of antimatter. And while we know high-energy positrons - the antimatter counterpart of the electron - can be caused by cosmic rays making contact with the atmosphere, or by particularly active lightning storms, what Dwyer detected could not be explained by either of these scenarios.

'This was so strange that we sat on this observation for several years,' Dwyer, from the University of New Hampshire in the US, told Davide Castelvecchi at Nature.

The flight in question took place on 21 August 2009, when Dwyer, then at the Florida Institute of Technology in Melbourne, Florida, set out to detect gamma rays (γ-rays) - extremely high-frequency electromagnetic radiation made up of high-energy photons. He installed a particle detector on a Gulfstream V aircraft, and flew it along the coast of Georgia. Unfortunately for Dwyer’s nerves, he ran into a line of thunderstorms, and had no choice but to fly right through them.

'During those frightening minutes, the detector picked up three spikes in γ-rays at an energy of 511 kiloelectronvolts, the signature of a positron annihilating with an electron,' says Castelvecchi."

edited 14th May '15 1:42:52 AM by rmctagg09

What happens when Newton's third law is broken?: "Even if you don't know it by name, everyone is familiar with Newton's third law, which states that for every action, there is an equal and opposite reaction. This idea can be seen in many everyday situations, such as when walking, where a person's foot pushes against the ground, and the ground pushes back with an equal and opposite force. Newton's third law is also essential for understanding and developing automobiles, airplanes, rockets, boats, and many other technologies.

Even though it is one of the fundamental laws of physics, Newton's third law can be violated in certain nonequilibrium (out-of-balance) situations. When two objects or particles violate the third law, they are said to have nonreciprocal interactions. Violations can occur when the environment becomes involved in the interaction between the two particles in some way, such as when an environment moves with respect to the two particles. (Of course, Newton's law still holds for the complete 'particles-plus-environment' system.)

Although there have been numerous experiments on particles with nonreciprocal interactions, not as much is known about what's happening on the microscopic level—the statistical mechanics—of these systems.

In a new paper published in Physical Review X, Alexei Ivlev, et al., have investigated the statistical mechanics of different types of nonreciprocal interactions and discovered some surprising results—such as that extreme temperature gradients can be generated on the particle scale."

Researchers develop liquid-crystal-based compound lenses that work like insect eyes: "Researchers have shown how liquid crystals can be employed to create compound lenses similar to those found in nature. Taking advantage of the geometry in which these liquid crystals like to arrange themselves, the researchers are able to grow compound lenses with controllable sizes."

Laser technique for low-cost self-assembly of nanostructures: "Researchers from Swinburne University of Technology and the University of Science and Technology of China have developed a low-cost technique that holds promise for a range of scientific and technological applications.

They have combined laser printing and capillary force to build complex, self-assembling microstructures using a technique called laser printing capillary-assisted self-assembly (LPCS).

This type of self-assembly is seen in nature, such as in gecko feet and the salvinia leaf, and scientists have been trying to mimic these multi-functional structures for decades.

The researchers have found they can control capillary force – the tendency of a liquid to rise in narrow tubes or be drawn into small openings – by changing the surface structure of a material."

edited 19th May '15 10:05:28 PM by rmctagg09

Fundamental magnetism discovery: New class of swelling magnets: "A new class of magnets that expand their volume when placed in a magnetic field and generate negligible amounts of wasteful heat during energy harvesting, has been discovered."

Controlling light: Scientists tune light waves by pairing exotic 2-D materials: "Researchers take control of light emission using paired 2-D materials. They say this has the potential to lead to new kinds of light detection, thermal-management systems, and high-resolution imaging devices."

Toward 'green' paper-thin, flexible electronics: "The rapid evolution of gadgets has brought us an impressive array of 'smart' products from phones to tablets, and now watches and glasses. But they still haven't broken free from their rigid form. Now scientists are reporting a new step toward bendable electronics. They have developed the first light-emitting, transparent and flexible paper out of environmentally friendly materials via a simple, suction-filtration method."

Physicists find ways to increase antihydrogen production: "There are many experiments that physicists would like to perform on antimatter, from studying its properties with spectroscopic measurements to testing how it interacts with gravity. But in order to perform these experiments, scientists first need some antimatter. Of course, they won't be finding any in nature (due to antimatter's tendency to annihilate in a burst of energy when it comes in contact with ordinary matter), and creating it in the lab has proven to be very technically challenging for the same reasons.

Now in a new paper published in Physical Review Letters, Alisher S. Kadyrov, et al., at Curtin University in Perth, Australia, and Swansea University in the UK, have theoretically found a method to enhance the rate of antihydrogen production by several orders of magnitude. They hope that their finding will guide antihydrogen programs toward achieving the production of large amounts of antihydrogen for long confinement times, and at cool temperatures, as required by future investigative experiments."

Nature inspires first artificial molecular pump: "Using nature for inspiration, a team of Northwestern University scientists is the first to develop an entirely artificial molecular pump, in which molecules pump other molecules. This tiny machine is no small feat. The pump one day might be used to power other molecular machines, such as artificial muscles.

The new machine mimics the pumping mechanism of life-sustaining proteins that move small molecules around living cells to metabolize and store energy from food. For its food, the artificial pump draws power from chemical reactions, driving molecules step-by-step from a low-energy state to a high-energy state—far away from equilibrium."

Defects can 'Hulk-up' materials: Properly managed damage can boost material thermoelectric performances: "In the story of the Marvel Universe superhero known as the Hulk, exposure to gamma radiation transforms scientist Bruce Banner into a far more powerful version of himself. In a study at Berkeley Lab, exposure to alpha-particle radiation has been shown to transform certain thermoelectric materials into far more powerful versions of themselves."

The Large Hadron Collider has just annhilated its own energy record: "If you thought the Large Hadron Collider was impressive before, new tests performed late Wednesday night show that this experiment is just getting warmed up. The collider, which famously found evidence of the Higgs boson in 2012, has just smashed beams of protons into each other at a record-breaking energy of 13 trillion electronvolts (TeV).

This is an increase of 60 percent on the collider's previous record of 8 TeV, and the new energy levels will allow researchers to generate larger particles than ever before and help them understand some of the biggest mysteries of our Universe, such as what dark energy is, and how gravity really works."

edited 22nd May '15 11:19:29 PM by rmctagg09

Visualizing how radiation bombardment boosts superconductivity: "Sometimes a little damage can do a lot of good—at least in the case of iron-based high-temperature superconductors. Bombarding these materials with high-energy heavy ions introduces nanometer-scale damage tracks that can enhance the materials' ability to carry high current with no energy loss—and without lowering the critical operating temperature. Such high-current, high-temperature superconductors could one day find application in zero-energy-loss power transmission lines or energy-generating turbines. But before that can happen, scientists would like to understand quantitatively and in detail how the damage helps—and use that knowledge to strategically engineer superconductors with the best characteristics for a given application."

In a paper published May 22, 2015, in Science Advances, researchers from the U.S. Department of Energy's (DOE) Brookhaven and Argonne national laboratories describe atomic-level 'flyovers' of the pockmarked landscape of an iron-based superconductor after bombardment with heavy ion radiation. The surface-scanning images show how certain types of damage can pin potentially disruptive magnetic vortices in place, preventing them from interfering with superconductivity."

From reverberating chaos to concert halls, good acoustics is culturally subjective: "Play a flute in Carnegie Hall, and the tone will resonate and fill the space. Play that same flute in the Grand Canyon, and the sound waves will crash against the rock walls, folding back in on each other in sonic chaos. The disparity in acoustics is clear - to the modern listener, the instrument belongs in an auditorium.

'Distinct echoes would be totally unforgivable in today's performance spaces,' says Steven J. Waller, an archaeo-acoustician who has studied prehistoric rock art and the acoustics of ancient performance spaces. 'But, in the past, people sought echoes.'

According to Waller, the response of audiences and performers to acoustic characteristics is a function of their worldview, and it is as fluid as the environment they inhabit. He will be presenting his findings this week at the 169th meeting of the Acoustical Society of America (ASA) in Pittsburgh."

Scientists have found a way to print incredible properties onto objects: "Inspired by the incredible nanostructures that make geckos' feet stick to walls, scientists have developed a new technique that allows them to laser-print objects that have complex and responsive properties.

This opens up the possibility to quickly and cheaply create materials that could greatly benefit science, technology and industry. Imagine materials that trap and release certain particles; self-cleaning objects; and super-adhesive structures.

Scientists know that these properties can all come from the complex layout of nano-pillars on the surface of an object, which control the way substances flow around them. But right now, they have to etch these surface features individually onto objects, which is time-consuming and expensive.

However, nature has a better way of doing it, known as 'self-assembly', which gives animals such as the gecko and plants like the hydrophobic salvinia leaf multi-functional nano-structures, and for decades scientists have been trying to mimic this ability.

Now researchers from Swinburne University of Technology in Australia and the University of Science and Technology in China have combined laser printing and something called 'capillary force' to find a way to quickly print structures with these self-assembling abilities."

edited 24th May '15 12:32:58 AM by rmctagg09

DNA double helix does double duty in assembling arrays of nanoparticles: "In a new twist on the use of DNA in nanoscale construction, scientists put synthetic strands of the biological material to work in two ways: They used ropelike configurations of the DNA double helix to form a rigid geometrical framework, and added dangling pieces of single-stranded DNA to glue nanoparticles in place."

Researchers first to create a single-molecule diode: "Under the direction of Latha Venkataraman, associate professor of applied physics at Columbia Engineering, researchers have designed a new technique to create a single-molecule diode, and, in doing so, they have developed molecular diodes that perform 50 times better than all prior designs. Venkataraman's group is the first to develop a single-molecule diode that may have real-world technological applications for nanoscale devices. Their paper, "Single-Molecule Diodes with High On-Off Ratios through Environmental Control," is published May 25 in Nature Nanotechnology."

The monopoly of aluminium is broken: "Discovering Majorana's was only the first step, but utilizing it as a quantum bit (qubit) still remains a major challenge. An important step towards this goal has just been taken, as shown by researchers from TU Delft in today's issue of Nature Physics.

It is an almost thirty years old scientific problem that has just been resolved: demonstrating the difference between the even and odd occupation of a superconductor in high magnetic fields. Thus far, this was only possible in aluminium which is however incompatible with Majorana's. This result enables the read out and manipulation of quantum states encoded in prospective Majorana qubits."

Protocol corrects virtually all errors in quantum memory, but requires little measure of quantum states: "Quantum computers are largely theoretical devices that could perform some computations exponentially faster than conventional computers can. Crucial to most designs for quantum computers is quantum error correction, which helps preserve the fragile quantum states on which quantum computation depends.

The ideal quantum error correction code would correct any errors in quantum data, and it would require measurement of only a few quantum bits, or qubits, at a time. But until now, codes that could make do with limited measurements could correct only a limited number of errors—one roughly equal to the square root of the total number of qubits. So they could correct eight errors in a 64-qubit quantum computer, for instance, but not 10.

In a paper they're presenting at the Association for Computing Machinery's Symposium on Theory of Computing in June, researchers from MIT, Google, the University of Sydney, and Cornell University present a new code that can correct errors afflicting a specified fraction of a computer's qubits, not just the square root of their number. And that fraction can be arbitrarily large, although the larger it is, the more qubits the computer requires."

Toward sold-state molecular circuitry: Molecular shuttle within a metal-organic framework: "In 1959 Moore observed that from the time the integrated circuit was invented, the number of transistors per square inch doubled about every eighteen months. A contemporary of Moore, Feynman, suggested that denser circuitry could be achieved by making molecular-scale circuitry. Since that time, mechanically interlocked molecules (MI Ms) have proven a viable contender for eventually making molecular-based circuitry, including molecular switches. However, most molecular switches are made and studied in solution.

Kelong Zhu, Christopher A. O'Keefe, V. Nicholas Vukotic, Robert W. Schurko and Stephen J. Loeb from the Department of Chemistry and Biochemistry at the University of Windsor have designed and characterized a molecular shuttle that functions both in solution and when placed within a rigid chemical structure called a metal-organic framework. Their work appears in Nature Chemistry."

Table-top extreme UV laser system heralds imaging at the nanoscale: "Researchers at Swinburne University of Technology have discovered a new way to generate bright beams of coherent extreme UV radiation using a table-top setup that could be used to produce high resolution images of tiny structures at the nanoscale."

Demonstration of room temperature spin transport in germanium: "A team of researchers working in Japan has demonstrated that it is possible to conduct a spin current through a short segment of germanium at room temperature. In their paper published in the journal Physical Review Letters, the team describes their technique which could help lead to the development of spintronic devices."

CERN scientists did an AMA.

Cool.

Donuts, math, and superdense teleportation of quantum information: "Quantum teleportation has been achieved by a number of research teams around the globe since it was first theorized in 1993, but current experimental methods require extensive resources and/or only work successfully a fraction of the time. Now, by taking advantage of the mathematical properties intrinsic to the shape of a donut — or torus, in mathematical terminology — a physicists have made great strides by realizing 'superdense teleportation.'"

What is an "AMA"?

Ask Me Anything.

Reddit thing for "Ask me Anything". Basically an open-forum vote-regulated Q&A with famous or important people.

New 'designer carbon' boosts battery performance: "Scientists have created a new carbon material that significantly improves the performance of batteries and supercapacitors."

Researchers prove magnetism can control heat, sound: "Phonons—the elemental particles that transmit both heat and sound—have magnetic properties, according to a landmark study supported by Ohio Supercomputer Center (OSC) services and recently published by a researcher group from The Ohio State University."

Graphene layer could quadruple rate of condensation heat transfer in generating plants: "Most of the world's electricity-producing power plants—whether powered by coal, natural gas, or nuclear fission—make electricity by generating steam that turns a turbine. That steam then is condensed back to water, and the cycle begins again.

But the condensers that collect the steam are quite inefficient, and improving them could make a big difference in overall power plant efficiency.

Now, a team of researchers at MIT has developed a way of coating these condenser surfaces with a layer of graphene, just one atom thick, and found that this can improve the rate of heat transfer by a factor of four—and potentially even more than that, with further work. And unlike polymer coatings, the graphene coatings have proven to be highly durable in laboratory tests."

Reality doesn’t exist until we measure it, quantum experiment confirms: "Australian scientists have recreated a famous experiment and confirmed quantum physics's bizarre predictions about the nature of reality, by proving that reality doesn't actually exist until we measure it - at least, not on the very small scale.

That all sounds a little mind-meltingly complex, but the experiment poses a pretty simple question: if you have an object that can either act like a particle or a wave, at what point does that object 'decide'?

Our general logic would assume that the object is either wave-like or particle-like by its very nature, and our measurements will have nothing to do with the answer. But quantum theory predicts that the result all depends on how the object is measured at the end of its journey. And that's exactly what a team from the Australian National University has now found."

Giant structures called plasmoids could simplify the design of future tokamaks: "Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) have for the first time simulated the formation of structures called 'plasmoids' during Coaxial Helicity Injection (CHI), a process that could simplify the design of fusion facilities known as tokamaks. The findings, reported in the journal Physical Review Letters, involve the formation of plasmoids in the hot, charged plasma gas that fuels fusion reactions. These round structures carry current that could eliminate the need for solenoids - large magnetic coils that wind down the center of today's tokamaks - to initiate the plasma and complete the magnetic field that confines the hot gas."

Novel X-ray lens sharpens view into the nano world: "A team led by DESY scientists has designed, fabricated and successfully tested a novel X-ray lens that produces sharper and brighter images of the nano world. The lens employs an innovative concept to redirect X-rays over a wide range of angles, making a high convergence power. The larger the convergence the smaller the details a microscope can resolve, but as is well known it is difficult to bend X-rays by large enough angles. By fabricating a nano-structure that acts like an artificial crystal it was possible to mimic a high refracting power. Although the fabrication needed to be controlled at the atomic level—which is comparable to the wavelength of X-rays—the DESY scientists achieved this precision over an unprecedented area, making for a large working-distance lens and bright images. Together with the improved resolution these are key ingredients to make a super X-ray microscope. The team led by Dr. Saša Bajt from DESY presents the novel lens in the journal Scientific Reports."

Physicists make first observation of the pushing pressure of light: "For more than 100 years, scientists have debated the question: when light travels through a medium such as oil or water, does it pull or push on the medium? While most experiments have found that light exerts a pulling pressure, in a new paper physicists have, for the first time, found evidence that light exerts a pushing pressure.

The scientists suggest that this apparent contradiction is not a fundamental one, but can be explained by the interplay between the light and the fluid medium: if the light can put the fluid in motion, it exerts a pushing force; if not, it exerts a pulling force."

Stretchable, biocompatible hydrogels with complex patterning for tissue engineering: "Researchers have developed a new way of making tough—but soft and wet—biocompatible materials, called "hydrogels," into complex and intricately patterned shapes. The process might lead to injectable materials for delivering drugs or cells into the body; scaffolds for regenerating load-bearing tissues; or tough but flexible actuators for future robots, the researchers say."

'New era' in physics as world's biggest particle smasher cranks up: "Scientists on Wednesday hailed a "new era" in their quest to unravel more mysteries of the universe as the world's biggest particle smasher started experiments with nearly doubled energy levels in a key breakthrough.

The tests at the European Organisation for Nuclear Research (CERN) came after a sweeping two-year revamp of the collider and will help scientists to study fundamental particles, the building blocks of all matter, and the forces that control them.

During its next run, researchers will look for evidence of "new physics" and probe "supersymmetry"—a theoretical concept informally dubbed Susy; seek explanations for enigmatic dark matter and look for signs of extra dimensions."

Proposed synchrotron could store supersonic beams of hydrogen atoms: "With a circumference of 27 km (17 miles), the Large Hadron Collider (LHC) holds the claim of being the largest particle accelerator in the world, but it is far from being the only device of its kind. Currently there are about 30,000 particle accelerators in operation around the world, many of them used in medicine and industrial applications, and some of them small enough to fit on a tabletop.

In a paper published in the New Journal of Physics, physicists from VU University Amsterdam and the University of Oxford have presented a design for a new one-meter-diameter magnetic synchrotron—a circular particle accelerator like the LHC—that could be used to study collisions between neutral hydrogen atoms and other atoms and molecules."

Catalyst that converts carbon dioxide to carbon monoxide in water: "Clean energy, or energy that comes from renewable sources, is of interest in the developing world. One path toward clean energy is harnessing solar energy and converting it into electrical energy, which could be done using a chemical process called Fischer-Tropsch. This process converts gaseous carbon monoxide and hydrogen into liquid hydrocarbons, which can then be used for fuel.

To take advantage of this potential source of fuel through the use of a renewable source, carbon dioxide, must be converted to carbon monoxide in a way that is industrially practical. This reaction requires a catalyst to obtain quantitative yields of carbon monoxide. Additionally, this reaction is typically done in non-aqueous solvents, which makes industrial-scale processes more difficult. Cyrille Costentin, Marc Robert, Jean-Michel Saveant, and Arnaud Tatin from the Laboratoire d'Electrochimie Moléculaire, Université Paris Diderot, Sorbonne Paris Cité, Unité Mixte de Recherche Université - CNRS have designed a catalyst that converts carbon dioxide to carbon monoxide in near-quantitative yields in water. This catalyst also allows for tunable production of carbon dioxide-to-hydrogen ratios by controlling the pH of the system. Their work appears in the Proceedings of the National Academy of Science."

edited 4th Jun '15 1:12:03 AM by rmctagg09

In tuning friction to the point where it disappears, technique could boost development of nanomachines: "Friction is all around us, working against the motion of tires on pavement, the scrawl of a pen across paper, and even the flow of proteins through the bloodstream. Whenever two surfaces come in contact, there is friction, except in very special cases where friction essentially vanishes—a phenomenon, known as 'superlubricity,' in which surfaces simply slide over each other without resistance.

Now physicists at MIT have developed an experimental technique to simulate friction at the nanoscale. Using their technique, the researchers are able to directly observe individual atoms at the interface of two surfaces and manipulate their arrangement, tuning the amount of friction between the surfaces. By changing the spacing of atoms on one surface, they observed a point at which friction disappears.

Vladan Vuletic, the Lester Wolfe Professor of Physics at MIT, says the ability to tune friction would be helpful in developing nanomachines—tiny robots built from components the size of single molecules. Vuletic says that at the nanoscale, friction may exact a greater force—for instance, creating wear and tear on tiny motors much faster than occurs at larger scales."

Would it be accurate to say that every natural phenomena like earthquake, storm, lightning, etc yields energy?