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The article reports that the Gravity Probe B spacecraft of the U.S. National Aeronautics and Space Administration (NASA) has confirmed the theory of gravity that was introduced by German theoretical physicist Albert Einstein, as revealed by researchers at a NASA press conference that was held in Washington, D.C. in 2011. It was confirmed that gravity results from mass that bends space and time. The spacecraft began circling the Earth on April 20, 2004.

The article reports on physicists' claim that it is still too early to know whether the particle discovered at the Large Hadron Collider in Switzerland in July 2012 is really the Higgs boson.

This article presents a study conducted by Ivette Fuentes-Schuller of the University of Oxford in Great Britain and Robert Mann of the University of Waterloo, Canada, on the connection between quantum mechanics and gravity. When two particles are entangled, fiddling with one instantly affects the other, even if it's light years away. Samuel Braunstein, a theoretical physicist at the University of York, said that the fact that entanglement depends on the motion of the observer is surprising.

Physicists have hoped that a flaw in Albert Einstein's special theory of relativity might reveal that space and time aren't smooth at the smallest scale, but fuzzy and foaming. Those hopes have been dashed by two independent measurements of cosmic gamma rays, which show that Einstein was right after all. Floyd Stecker, a theoretical astrophysicist at the Goddard Space Flight Center of NASA, and colleagues studied gamma rays from the hearts of two galaxies, some 450 million light-years from Earth. En route the rays pass through a haze of infrared photons that fill intergalactic space. If Lorentz invariance were violated, the gamma rays would zip right through the haze. According to special relativity, however, the highest energy gamma rays should collide with the infrared photons to make electron-antielectron pairs. Gamma rays from the Crab Nebula also bear out Einstein's theory. These rays come from extremely energetic electrons spiraling in the magnetic fields inside the gargantuan cloud of gas. If Lorentz invariance were violated, the electrons would slam up against a virtual speed limit slower than the speed of light. From the energy of the gamma rays, however, Jacobson and colleagues deduced that electrons were traveling within a 10-billion-billionth of the speed of light, even stronger evidence that Einstein was right.

The article reports that D-Wave Systems, a upstart technological company in Burnaby, British Columbia have developed adiabatic quantum computing or quantum annealing. A quantum computer would use subatomic particles or other quantum objects as qubits that could be encoded 0, 1 or both 0 and 1. A quantum computer could process myriad inputs at once and solve problems but the gate model approach to quantum computing presents many unresolved practical problems.

The article presents an analysis regarding better suspension bridge arrangement. The author is critical on the arrangement in suspension bridges like the Golden Gate Bridge in San Francisco, California wherein a heavy roadway is suspended by thin hangers from two main cables stretching between two towers. Furthermore, the views of several engineers concerning the mentioned issue and their recommendations are also discussed.

The article reports that tiny, tight-cornered channels etched into a piece of glass dry out far faster than round ones do and at the same rate regardless of the humidity. Researchers Jan Eijkel, Albert van den Berg, and colleagues at the University of Twente in Enschede, the Netherlands, have stumbled across a novel way to make even faster-drying channels. The researchers created the channels by etching troughs 72 nanometers deep and from 2 to 30 micrometers wide in a piece of glass and then bonding a second piece on top of the first.

The article presents information on three researchers who have been honored by the 2005 Nobel Prize in physics. They pioneered the frontier between the wave and particle views of light and laid the foundation for the field of "quantum optics." Theorist Roy Glauber received half the prize for mapping out the conceptual connection between assemblages of individual photons and classical waves of light. Experimentalists Theodor Hänsch, and John Hall share the other half for developing exquisitely precise techniques to manipulate laser light, which is a quantum-mechanical torrent of photons.

The article reports that the U.S. National Science Foundation (NSF) recently withdrew its support for a high-energy physics project planned for the Department of Energy's Brookhaven National Laboratory after deciding that its budget could not handle the soaring costs. The decision, unusual for NSF, effectively kills the Rare Symmetry Violating Processes (RSVP) project just before construction was to begin on its two massive detectors. RSVP consisted of twin experiments, one to see if a subatomic particle called the muon could transform into an electron, and another to look for unexpected differences in the behavior of matter and antimatter.

The article focuses on the statement made by a theoretical physicist that, a single, simply calculated number provides a rough estimate of the impact of any particular scientist's work From deciding whether to tenure a junior faculty member to selecting the winner of a prestigious prize, researchers often face the challenge of objectively evaluating the importance of a colleague's work. Committees may weigh quantitative measures of a scientist's productivity, such as the number of papers published or the number of citations those papers have amassed. But one easily determined number provides a more reliable measure of the impact of a researcher's work.

This article cites a study conducted by researcher Kerry Vahala and colleagues at the California Institute of Technology in Pasadena, which states that light pressure can excite mechanical vibration in a tiny silica disk. The disk is an optical microcavity, a device that resonates with light much as a soda bottle will resonate with sound, and a cousin of the microcavities that currently narrow the laser beams in CD and DVD players. The researchers strung an optical fiber along side the edge of the tens-of-micrometers-wide microcavity, and light from the fiber bled into the disk and raced around its rim.

The article informs that physicists have struggled for long to fully explain the "Brazil-nut effect"--the fact that shaking a can of mixed nuts or other granular materials drives the larger objects to the top and the smaller ones to the bottom. Now researchers have discovered that marbles swirling in a pan sort themselves out in much the same way. Because the marble model only involves horizontal motion, it may provide scientists with a simpler system for deciphering the Brazil-nut effect. The Brazil nut effect is useful for separating the wheat from the chaff, but it can also be a major nuisance, when mixing sand and gravel for concrete, for example.

The article reports that physicists have been racing to prove that ultracold atoms can pair up and flow like the freely flowing electrons in a superconductor. Now, subtle swirls in a cloud of atoms provide positive proof that researchers have reached that elusive goal. For more than a decade, physicists have used laser beams and magnetic fields to chill gases of atoms to within billionths of a degree of absolute zero, producing a variety of weird quantum effects. Atoms of some isotopes can crowd into a single quantum wave, or "state," to create a Bose-Einstein condensate.

The article reports that a stack of high-technology blocks can copy itself. Mechanical engineer Gregory Chirikjian and colleagues at Johns Hopkins University in Baltimore, Maryland, have built miniature bulldozers out of Legos that can assemble others of their kind by piecing together several previously assembled modules, such as chassis and tracks. Other mechanical engineers have developed a system that conceptually falls somewhere between simple tiles and half-assembled machines. Victor Zykov, Hod Lipson, and colleagues at Cornell University in Ithaca, New York, built high-technology cubical blocks measuring about 10 centimeters on a side.

The article reports that researchers have employed bacteria to line up nanometer-sized tubes of carbon on the surface of a silicon chip. Resembling miniature rolls of chicken wire, nanotubes are super-strong and can conduct electricity much like the materials in microchips. According to physical chemist Jong-in Hahm and colleagues at Pennsylvania State University in University Park, bacteria can line up the tubes relatively easily and inexpensively.

The article informs that scientists have developed a compact magnetic sensor that can tell one compound from another. The advance could lead to a new type of portable chemical analyzer to monitor production at chemical plants or detect explosives. The device is based on nuclear magnetic resonance (NMR), a technique that identifies the elements in a chemical compound by tracking how atomic nuclei within the compound wobble in a magnetic field. NMR can even detect how a particular element bonds to others by sensing the small magnetic fields created by the bonds.

The article reports on a study in which researchers have studied the distribution of droplet sizes and energies in splashes. Physicists Lei Xu, Sidney Nagel, and colleagues at the University of Chicago were searching for ways to control those sizes and energies when they discovered something unexpected. By pumping away some of the surrounding air they could eliminate the splatter entirely. The droplets struck the surface with speeds ranging from 2 to 7 meters per second, and for a given speed, the researchers found they could eliminate the splash by lowering the pressure beyond a specific threshold.

The article informs that a fly's eye contains a striking hexagonal pattern of individual lenses and photoreceptors. Yet this complex array forms through a simple process that does not require any sophisticated instructions for assembly. The trick may be another tool nature uses to create exquisite biological structures. From the graceful spirals in the faces of sunflowers to the intricate segmentation of insect bodies, nature abounds with complex patterns.

This article focuses on a new technique that uses a simple gas-filled chamber to detect the wobbling of atomic nuclei, which may lead to cheaper, faster and portable magnetic resonance imaging (MRI) machines. MRI works because atomic nuclei act like small bar magnets. The wobbling nuclei generate their own oscillating magnetic field, which can be used to create an image. Researchers Igor Savukov and Michael Romalis of Princeton University in New Jersey have detected the oscillating field with an exquisitely sensitive sensor called an "atomic magnetometer." Placing a water sample next to the magnetometer, the researchers measured the oscillating field produced by protons exposed to a magnetic field.

The article informs that a fly's eye contains a striking hexagonal pattern of individual lenses and photoreceptors. Yet this complex array forms through a simple process that does not require any sophisticated instructions for assembly. The trick may be another tool nature uses to create exquisite biological structures. From the graceful spirals in the faces of sun flowers to the intricate segmentation of insect bodies, nature abounds with complex patterns. Yet, explaining precisely how these patterns form remains a challenge. Genes cannot specify every detail, so at least in part, the forms must emerge spontaneously through some physical mechanism.

The article reports that physicists have proved that salt crystals growing in nanometer-sized pores exert tremendous pressure on the pore walls. Many researchers believe that salt damages stone when crystals form inside the stone's tiny pores. Water carries salt from the environment into a pore, and, as salt crystals precipitate out of the solution and expand, they run into the pore wall. If the natural properties of the salt and stone cause them to repel each other, the crystal will push against the stone with enormous force as it continues to grow. Or so the theory goes. No one has measured such crystallization pressure.

The article focuses on a new research, which indicates that the space between stars contains twice as much cold gas as previously thought. The gas might provide enough gravity to keep the galaxy from flying apart, eliminating the need for mysterious dark matter. Researchers measure the amount of warmer atomic hydrogen by tracking radio waves emitted by the atoms. But to spot the colder hydrogen, which emits no easily detectable signal, researchers must measure radio waves emitted by carbon monoxide and assume that the two molecules are found together in a certain ratio.

The article focuses on the management at the Stanford Linear Accelerator Center (SLAC) which routinely overlooked safety violations to keep the lab's particle accelerators running. That's the conclusion of the U.S. Department of Energy (DOE) investigation into a serious electrical accident at the DOE high-energy physics facility in Menlo Park, California. The October 11, 2004 accident occurred when an electrician tried to install a circuit breaker in a 480 volt power panel without shutting off electricity to the panel, a practice known as "hot work." The accident automatically triggered the inquiry by DOE's Office of Environment, Safety, and Health.

The article reports that inside a molecule, an orbital containing a pair of electrons can collide with itself. The collision produces light, and now physicists have used that light to generate the best image yet of such an orbital. The trick is to use a pulse of laser light lasting only a few millionths of a nanosecond to pull part of the orbital away from the molecule and then accelerate it back toward it. By plucking the outer orbital of a nitrogen molecule from 19 different angles, the researchers pieced together an image that confirmed its dumbbell shape.

The article informs that in the 1997 best-seller, "The Perfect Storm," three storms merge to form a gargantuan hurricane. Now, physicists have produced the quantum mechanical equivalent by forcing several tiny whirlpools of current in a superconductor to merge into a single" giant vortex." The magnetic field threads the eyes of the" vortices," and thanks to quantum mechanics, each vortex contains precisely one fundamental quantum of" magnetic flux." If the superconductor is tiny, however, the cramped vortices ought to form more exotic patterns and should even merge into one jumbo vortex containing several quanta of magnetic flux.

The article reports that in the past 2 years, astrophysicists and cosmologists have nailed down the age and composition of the universe by studying the all-pervading radiation left over from the big bang. But subtleties in that cosmic microwave background (CMB) suggest that our own solar system may be producing or absorbing some of the microwaves, a team of astrophysicists reports. The radiation in the CMB has lingered since atoms first formed some 300,000 years after the big bang, stretching to ever-longer wavelengths as the universe expanded and cooled.

The article reports new measurements which show that the basilisks generate large sideways forces that keep them from tripping over the liquid. In 1996, biologists James Glasheen of the University of California, Berkeley, and Thomas McMahon of Harvard University in Cambridge, Massachusetts, videotaped basilisks and measured the forces on a model basilisk foot dropped into water to figure out the relative contributions of the slapping and paddling that keep the lizard's head above water. But a basilisk must also remain steady, and new measurements show that the lizard pushes nearly as hard side to side to avoid tripping.

The article focuses on a study in which biomedical engineers discovered the underlying physical principle while studying blood cells gliding through capillaries. According to researchers, a moving blood cell rides on the fluid trapped in the gel, which cannot seep through the material fast enough to get out of the way. When the cell comes to a halt, however, the fluid has time to ooze out from under it, so the cell bogs down. In the same way, a snowboarder rides the air trapped in fresh snow, not the snow itself.

The article reports that a physics laboratory of the U.S. Department of Energy has shut down its particle accelerators indefinitely after an accident left a worker badly burned. On 11 October, 2004, an electric discharge struck a technician at the Stanford Linear Accelerator Center (SLAC) in Menlo Park, California, while he replaced a circuit breaker near a 480-volt power panel. The linear accelerator was running at the time of the accident and was shut down immediately. The worker is in serious condition at a nearby burn center.

The article informs that falling leaves and tumbling sheets of paper can momentarily float upward against gravity as they flutter through still air. The fluttering, looping, and tumbling motions of falling sheets of paper and other flat objects have fascinated thinkers since the 19th century, when famed Scottish physicist James Clerk Maxwell studied falling cards. But previous analyses have not realistically explained how a tumbling sheet rises against gravity as it flips over. According to Z. Jane Wang and Umberto Pesavento of Cornell University in Ithaca, New York, there is another way to produce aerodynamic lift.

The article focuses on the new method, which works without cumbersome vacuum chambers and specially prepared samples. As per experts it could be used in airports to" sniff" luggage for traces of explosives, in orchards to test fruit for pesticide residues, and in many other venues outside the laboratory. A new way of making ions could revolutionize the venerable practice of mass spectrometry, in which ionized molecules are identified by their weight. Dubbed Desorption Electrospray Ionization (DESI), resembles techniques in which beams of ions or laser light blast ions from a sample for analysis.

The article focuses on study according to which laser light traveling through plasma can produce a beam of electrons all with nearly the same energy. The advance, reported in the September 30, 2004 issue of the journal Nature, marks a key step toward developing practical high-energy particle accelerators that can fit into a room. In recent decades, physicists have experimented with accelerating particles by shining extremely intense pulses of laser light into an ionized gas, or plasma. As the light pulse travels through the plasma, it pushes negatively charged electrons, creating a region of excess positive ions that trails behind the light.

The article presents information about a new wetsuit automatically adjusts to keep divers warmer in cold water which is designed for commandos. The underlying technology could have other uses in sports, such as smoothing out the swimsuits of competitive swimmers. As its name implies, a wetsuit lets in water that then insulates the body. The key to the suit is a new material called SmartSkin. The researchers tuned the gel to absorb 20 to 30 times its original volume of water when temperatures dipped below 20° C. Tank tests showed that in 25° water the suit was as cool as a conventional suit.

The article presents information that the large, light volleyball routinely enters a curious aerodynamic state rarely seen with other balls. The key factor is drag, and its effects depend on speed. Not so for volleyball, reports Thomas Cairns, a mathematician at the University of Tulsa in Oklahoma who coached the women's volleyball team there for 17 years. In spite of its name, the lift ordinarily pushes a ball with top spin down, so that it sinks faster than a similar serve with no spin. Certain players already take advantage of strange aerodynamic effects, too, says Rabindra Mehta, an aerodynamicist at NASA's Ames Research Center in Moffett Field, California.

The article reports on a new mechanical analysis, which suggests that counterproductive efforts while throwing balls etc infact enable the limb to fling the ball farther. The body briefly continues to move downward even after the muscles in the legs and torso begin to pull it upward, and when moving one way and pulling the other, the body does mechanical work against itself and wastes energy. Similarly, in throwing, the forearm momentarily moves backward even as the upper arm pulls it forward, again squandering energy.

For more than a century, scientists have puzzled over how the smooth flow of a liquid through a pipe suddenly erupts into a chaotic tangle of eddies and swirls. Since 1990, however, theorists have used computer simulations to piece together a novel explanation of turbulence in pipes. Engineer Casimir van Doorne of Delft University of Technology in the Netherlands and his colleagues sent water through a long pipe, 4 centimeters in diameter, that was designed to suppress turbulence. A jet mounted on the side of the pipe disturbed the flow and a laser and cameras 6 meters downstream tracked the motion of beads in the water. They observed vortices that shoved faster water toward the sides of the pipe and slower water toward the center, creating long streaks of slower and faster moving water stretching along the pipe.

A disk of dust surrounding a nearby star contains lumps and other signs of rocky planets coming together. The second of its kind, the new observation suggests that many young stars are surrounded by colliding boulders. Based on a handful of observations, astronomers have a rough idea of how a new solar system forms. First a star coalesces from a swirling disk of dust and gas. Then, in less than 10 million years, gaseous planets similar to Jupiter and Saturn come together, gobbling up the leftover gas. After that, rocks, boulders, and "planetesimals" begin to collide, kicking up a whole new disk of dust and, over many millions of years, creating rocky planets similar to Earth and Mars.

An electric field can cause two thoroughly mixed liquids to separate, researchers have shown. Oil and water may never mix, but many combinations of two liquids are not so strict. If the field is spatially uniform, it must be extremely strong— stronger than the fields that drive lightening through air— and the mixture must be within a few hundredths of a degree of the critical temperature. However, an uneven electric field neatly pulls the liquids apart at lower field strengths and a wider range of temperatures, physical chemist Ludwik Leibler and colleagues at the City of Paris Industrial Physics and Chemistry Higher Educational Institution report in the 29 July, 2004 issue of Nature.

Newly designed molecules can spontaneously snap together to form three interlocking rings. For decades, practitioners of" topological chemistry" have sought ways to intertwine molecules in ever more elaborate patterns. In particular, researchers have striven to synthesize a molecular version of the Borromean rings— three rings laced together in such a way that cutting any one allows the other two to fall apart. In 1997, researchers succeeded in fashioning a version from specially coded DNA, but even then the twisted molecule looked more like a wadded up rubber band than three distinct rings.

The article focuses on the observation of astronomers and astrophysicists on the expansion of the universe. Measurements of x-rays from far-flung clusters of galaxies bolster previous estimates from supernovae and the cosmic background radiation. In 1998, two independent research teams reached the stunning conclusion that some distant exploding stars were farther away than they would be if expansion were constant or slowing down as expected. Researchers working with the Wilkinson Microwave Anisotropy Probe satellite measured tiny spatial variations in the cosmic microwave background and deduced that the universe must consist mainly of space-stretching "dark energy."

The article presents results of a experiment which reveals that a triangular nozzle squeezes out a smaller droplets than a circular one does. Henry Chen, a physicist, and Michael Brenner, a mathematician at Harvard University in Cambridge, Massachusetts, with the aid of a computer analyzed the stability of the droplets bulging from nozzles of various shapes with the same area. They tracked the critical pressure as the shape of the nozzle deviated further from a circle. At a given critical pressure, a triangular nozzle with stretched corners produces drops 20% smaller than those squirting from a circular nozzle.

Without using atomic nuclei, physicists have demonstrated a strange asymmetry in the weak nuclear force, a fundamental force of nature. In a certain type of nuclear decay, an atomic nucleus spits out an electron and a particle called an antineutrino that always spins to the right as it zings along, like a football flung by a right-handed quarterback. The mirror-image decay, in which the antineutrino spins to the left, never occurs. That asymmetry is known as parity violation and is a defining characteristic of the weak nuclear force, which causes such radioactive decay. According to the Standard Model of particle physics, the electromagnetic force with which electrons push each other and the weak nuclear force are really two aspects of a single underlying" electroweak" force that bleed into each other. The researchers looked for subtle differences in the probability that right-spinning and left-spinning electrons would ricochet slightly. The teams report the results in a paper to be published in Physical Review Letters.

Generally tightly packed objects cannot roll against one another without causing friction somewhere. It is possible to pack spheres together so that they all roll smoothly and no two rub against each other. If the plane is covered with disks of an infinite variety of sizes in certain patterns, as theoretical physicist Hans Herrmann of the University of Stuttgart in Germany and colleagues demonstrated in the 1980's. To construct the "space-filling bearing," researchers envisioned a large sphere with six smaller spheres arranged inside as if they were on corners of a regular octahedron.

The article focuses on a report from a team of Russian and American scientists, which states that two new elements have emerged from the rubble of nuclear collisions. Nuclear physicists and chemists have long known that certain atomic nuclei hold together better than others. In recent years nuclear physicist Yuri Oganessian of the Joint Institute for Nuclear Research in Dubna, Russia, nuclear chemists Mark Stoyer and Kenton Moody of Lawrence Livermore National Laboratory in California, and their colleagues have succeeded in producing elements 114 and 116 by slamming calcium nuclei into heavier nuclei.

The faster it comes in, the faster it goes out, baseball players sometimes say, meaning that the easiest pitch to hit over the outfield fence is a fastball. But although it seems obvious that, when hit, the fastest pitch will fly farthest, calculations suggest that a properly struck curveball outdistances a well-hit fastball--even though the curveball is significantly slower. Employing mechanics and hydrodynamics, computer simulations and laboratory experiments, they have shown that a curveball really does curve and a "rising fastball" sinks, inspite of some baseball aficionados' belief that a curveball is an optical illusion and the rising fastball defies gravity.

The U.S. Department of Energy (DOE) has ranked 28 major science facilities it hopes to construct in the next 20 years. Topping the DOE wish list is a multibillion dollar nuclear fusion reactor, followed by a plan to build supercomputing infrastructure. The DOE Office of Science set out last year to evaluate and rank the department's proposed major science facilities. Marking another chapter in its spectacular comeback, the International Thermonuclear Fusion Reactor (ITER) experiment stands alone as DOE's number one future science project. ITER aims to achieve a self-sustaining fusion reaction by heating a mixture of deuterium and tritium, to hundreds of millions of degrees. Spain, France and Japan are competing to host the machine. The U.S. will likely foot 10% of the bill for the $5 billion experiment.

A plucky little spacecraft may have passed into a strange and unexplored region near the edge of the solar system. If so, then for the first time a humanmade object has reached the verge of interstellar space. The sun creates a kind of bubble that shields the solar system from interstellar space. A torrent of particles flows from the sun, and this solar wind gushes in all directions at supersonic speeds. Far beyond the planets, the solar wind slows to subsonic speeds, and that transition creates a shock wave. Past that "termination shock," the solar wind tapers and eventually melds with the interstellar medium at the edge of the solar system, which is called the heliopause. Scientists are hoping to observe the U.S. National Aeronautics and Space Administration far-flung Voyager 1 and Voyager 2 spacecraft pass into the little-understood region between transition shock and heliopause.

The face of the sun is now breaking out in more magnetic storms, known as sunspots, than at any other time in the previous millennium, a team of physicists reports. The unusual solar activity might account for some of the warming of Earth's climate. But some researchers say the evidence for increased activity are less. To gauge earlier activity, researchers study rare isotopes whose concentration varies with the magnetic activity on the sun. Detailed models now provide a precise calculation of sunspot history, Ilya Usoskin of the University of Oulu, Finland, Sami Solanki of the Max Planck Institute for Aeronomy in Katlenburg-Lindau, Germany, and colleagues merge together three models, one that relates the number of sunspots to the strength of the sun's magnetic field, another that shows how field strength determines the number of cosmic rays, and a third that accounts for how rays produce beryllium-10. Researchers say, since the 1940s, the sun has shown nearly twice as many spots as it did during any equal time period in the preceding millennium. Results tighten the link between beryllium-10 and solar magnetic fluctuations.

On its way to the planet Saturn, NASA's Cassini-Huygens spacecraft has tested mathematician Albert Einstein's theory of gravity to unprecedented precision. In 1915, Einstein posited that gravity is nothing other than the bending of space and time. Matter and energy warp space and time and a freely falling object travels along the nearest equivalent to a straight line in the curved space time terrain. Known as general relativity, this theory has become a pillar of modern physics. To Einstein's credit, the shifts agreed with the space time-bending predictions of general relativity to within 20 parts per million.

A team of theoretical physicists have reported that strategic navigating may exacerbate congestion. Heavy traffic would flow more smoothly, they say, if drivers choose their routes at random. Physicists have modeled city drivers reacting to one another as they fight their way across a grid of streets. When traffic becomes too dense, a tentacular traffic jam spreads across the city. In such simulations, however, drivers respond to only what is near their bumpers, rather than planning to avoid traffic. But even drivers who think ahead won't necessarily beat traffic. These results show that "too much intelligence" can impede traffic.