Physics
Competition in the quantum world
May 20, 2013 9:24 am | News | CommentsUsing a new tool called a quantum simulator—based on a small-scale quantum computer—researchers in Austria have simulated physical phenomena a classical computer cannot investigate efficiently. Scientists there are the first to have simulated the competition between two rival dynamical processes at a new type of transition between two quantum mechanical orders
Study: Earth's iron core is surprisingly weak
May 17, 2013 10:54 am | News | CommentsThe massive ball of iron sitting at the center of Earth is not quite as "rock-solid" as has been thought, say two Stanford University mineral physicists. By conducting experiments that simulate the immense pressures deep in the planet's interior, the researchers determined that iron in Earth's inner core is only about 40% as strong as previous studies estimated.
Stacking 2D materials produces surprising results
May 17, 2013 7:46 am | by David L. Chandler, MIT News Office | News | CommentsGraphene has dazzled scientists ever since its discovery more than a decade ago. But one long-sought goal has proved elusive: how to engineer into graphene a property called a band gap, which would be necessary to use the material to make transistors and other electronic devices. New findings by Massachusetts Institute of Technology researchers are a major step toward making graphene with this coveted property.
Flowers self-assemble in a beaker
May 16, 2013 2:46 pm | News | CommentsWith the hand of nature trained on a beaker of chemical fluid, the most delicate flower structures have been formed in a Harvard University laboratory—and not at the scale of inches, but microns. These minuscule sculptures, curved and delicate, don't resemble the cubic or jagged forms normally associated with crystals, though that's what they are. Rather, fields of flowers seem to bloom from the surface of a submerged glass slide.
Physicists discover a new kind of friction
May 15, 2013 11:26 am | News | CommentsIn a quest to develop low-friction components for ever smaller mechanical systems, a team of physicists in Germany has recently discovered a previously unknown type of friction that they call “desorption stick.” The researchers examined how and why single polymer molecules in various solvents slide over or stick to certain surfaces. They found that an unexpected factor was responsible for the friction they observed.
Physicists light “magnetic fire” to reveal energy's path
May 13, 2013 3:27 pm | News | CommentsResearch on bursts of energy within magnetic systems dates back two decades. But scientists haven't been able to measure and understand what prompts this phenomenon, known as "magnetic deflagration." New York University physicists have uncovered how energy is released and dispersed in magnetic materials in a process akin to the spread of forest fires.
The mechanism that puts the curl in the curling stone revealed
May 13, 2013 3:10 pm | News | CommentsIn the curling sport, the players shoot their stones along the ice so that they slowly slide towards the target area, almost 30 m away. The game has its name from the slightly curved "curled" path taken by the stone, when released with a slow rotation. Researchers from Uppsala University in Sweden can now reveal the mechanism behind this curving path.
Graphene joins the race to redefine the ampere
May 13, 2013 10:00 am | News | CommentsA new joint innovation by the National Physical Laboratory and the University of Cambridge could pave the way for redefining the ampere in terms of fundamental constants of physics. The world's first graphene single-electron pump provides the speed of electron flow needed to create a new standard for electrical current based on electron charge.
Feynman's double-slit experiment preserved
May 13, 2013 8:05 am | News | CommentsDescribed as the "most beautiful experiment in physics," Richard Feynman emphasized how the diffraction of individual particles at a grating is an unambiguous demonstration of wave-particle duality and contrary to classical physics. A research team recently used carefully made fluorescent molecules and nanometric detection accuracy to provide clear and tangible evidence of the quantum behavior of large molecules in real time.
Mathematics of popping bubbles in a foam
May 10, 2013 7:42 am | News | CommentsBubble baths and soapy dishwater and the refreshing head on a beer: These are foams, beautiful yet ephemeral as the bubbles pop one by one. Now, a team of researchers has described mathematically the successive stages in the complex evolution and disappearance of foamy bubbles, a feat that could help in modeling industrial processes in which liquids mix or in the formation of solid foams such as those used to cushion bicycle helmets.
Temporal filtering technique improves solid-state single photon sources
May 9, 2013 3:21 pm | News | CommentsAn international collaboration led by researchers at NIST has demonstrated a novel temporal filtering approach that improves the performance of triggered single photon sources based on solid-state quantum emitters. The technique is compatible with a broad class of photon sources, and is expected to provide significant improvements in areas important for applications in photonic quantum information science.
Exotic atoms hold clues to unsolved physics puzzle
May 9, 2013 7:47 am | News | CommentsAn international team of physicists has found the first direct evidence of pear-shaped nuclei in exotic atoms. The findings could advance the search for a new fundamental force in nature that could explain why the Big Bang created more matter than antimatter—a pivotal imbalance in the history of everything.
Scientists find new magic in magnetic material
May 8, 2013 4:04 pm | News | CommentsFrom powerful computers to super-sensitive medical and environmental detectors that are faster, smaller, and use less energy—yes, we want them, but how do we get them? In research that is helping to lay the groundwork for the electronics of the future, University of Delaware scientists have confirmed the presence of a magnetic field generated by electrons which scientists had theorized existed, but that had never been proven until now.
Explaining energy shifts in optical tweezers
May 8, 2013 12:26 pm | News | CommentsPhysicists working with optical tweezers have conducted work to provide an all-in-one guide to help calculate the effect the use of these tools has on the energy levels of atoms under study. This effect can change the frequency at which atoms emit or absorb light and microwave radiation and skew results; the new findings should help physicists foresee effects on future experiments.
Quantum optics demonstrated with microwaves
May 8, 2013 12:21 pm | News | CommentsPhysicists in Switzerland have demonstrated one of the quintessential effects of quantum optics—known as the Hong-Ou-Mandel effect—with microwaves, which have a frequency that 100,000 times lower than that of visible light. The experiment takes quantum optics into a new frequency regime and could eventually lead to new technological applications.
Research makes advance in nanotech gene sequencing technique
May 8, 2013 8:09 am | News | CommentsThe allure of personalized medicine has made new, more efficient ways of sequencing genes a top research priority. One promising technique involves reading DNA bases using changes in electrical current as they are threaded through a nanoscopic hole. Now, a team led by University of Pennsylvania physicists has used solid-state nanopores to differentiate single-stranded DNA molecules containing sequences of a single repeating base.
Study looks at muscle adaptations in minimalist runners
May 7, 2013 11:22 am | by Fariss Samarrai, University of Virginia | News | CommentsDespite the perceived advantages of foot protection, some runners in recent years have returned to barefoot running, believing it is a more natural way to run and therefore less injurious to the feet and legs. The difference results in a different running stride, and it affects how the muscles of the legs and feet respond and develop. A new study attempts to explain exactly how the muscles respond to this change.
Scientists discover 3D magnetic vortices
May 7, 2013 11:15 am | News | CommentsMagnetic vortices typically occur in nanometer-scale magnetic disks, which are studied for their potential roles in wireless data transmission. So far, magnetic vortex states have been observed only within a plane, but recently researchers in Europe have discovered 3D magnetic vortices for the first time in a specially designed stack of magnetic disks.
Observations of massive neutron star confirm relativity theory
May 1, 2013 12:01 pm | News | CommentsAn international research team led by astronomers from the Max Planck Institute for Radio Astronomy used a collection of large radio and optical telescopes to investigate in detail a pulsar that weighs twice as much as the sun. This neutron star, the most massive known to date, has provided new insights into the emission of gravitational radiation and serves as an interstellar laboratory for general relativity in extreme conditions.
Research find quantum phenomena can have effect on molecular level
April 29, 2013 10:42 am | News | CommentsUsing uniquely sensitive experimental techniques, scientists have found that laws of quantum physics—believed primarily to influence at only sub-atomic levels—can actually impact on a molecular level. The study shows that movement of the ring-like molecule pyrrole over a metal surface runs counter to the classical physics that govern our everyday world.
Researchers design nanometer-scale material that can speed up, squeeze light
April 29, 2013 10:03 am | News | CommentsIn a process comparable to squeezing an elephant through a pinhole, researchers at Missouri University of Science and Technology have designed a way to engineer atoms capable of funneling light through ultrasmall channels. Their research is the latest in a series of recent findings related to how light and matter interact at the atomic scale.
Physicists, biologists unite to expose how cancer spreads
April 29, 2013 8:03 am | News | CommentsCancer cells that can break out of a tumor and invade other organs are more aggressive and nimble than nonmalignant cells, according to a new multi-institutional nationwide study. These cells exert greater force on their environment and can more easily maneuver small spaces.
Understanding the turbulence in plasmas
April 29, 2013 7:49 am | by David L. Chandler, MIT News Office | News | CommentsOne simple phenomenon explains why practical, self-sustaining fusion reactions have proved difficult to achieve: Turbulence in the superhot, electrically charged gas, called plasma, that circulates inside a fusion reactor can cause the plasma to lose much of its heat. This prevents the plasma from reaching the temperatures needed to overcome the electrical repulsion between atomic nuclei. Until now.
What did Alexander Graham Bell's voice sound like?
April 26, 2013 8:34 am | News | CommentsLawrence Berkeley National Laboratory’s sound-restoration experts have done it again. They’ve helped to digitally recover a 128-year-old recording of Alexander Graham Bell’s voice, enabling people to hear the famed inventor speak for the first time. The recording ends with Bell saying “in witness whereof, hear my voice, Alexander Graham Bell.”
Light bursts out of a flying mirror
April 24, 2013 10:31 am | by Thorsten Naeser, MPQO | News | CommentsAn international team of physicists have successfully staged “thought experiment” formulated in 1905 by Albert Einstein stating that the reflection from a mirror moving close to the speed of light could, in principle, result in bright light pulses in the short wavelength range.
