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In 1967, Simon Kochen and Ernst Specker proved mathematically that even for a single quantum object, where entanglement is not possible, the values that you obtain when you measure its properties depend on the context. So the value of property A, say, depends on whether you chose to measure it with property B, or with property C. In other words, there is no reality independent of the choice of measurement. It wasn't until 2008, however, that Alexander Klyachko of Bilkent University in Ankara, Turkey, and colleagues devised a feasible test for this prediction. They calculated that if you repeatedly measured five different pairs of properties of a quantum particle that was in a superposition of three states, the results would differ for the quantum system compared with a classical system with hidden variables. That's because quantum properties are not fixed, but vary depending on the choice of measurements, which skews the statistics. "This was a very clever idea," says Anton Zeilinger of the Institute for Quantum Optics, Quantum Nanophysics and Quantum Information in Vienna, Austria. "The question was how to realise this in an experiment." Now he, Radek Lapkiewicz and colleagues have realised the idea experimentally. They used photons, each in a superposition in which they simultaneously took three paths. Then they repeated a sequence of five pairs of measurements on various properties of the photons, such as their polarisations, tens of thousands of times. A beautiful experiment They found that the resulting statistics could only be explained if the combination of properties that was tested was affecting the value of the property being measured. "There is no sense in assuming that what we do not measure about a system has [an independent] reality," Zeilinger concludes.

Princeton engineers have made a breakthrough in an 80-year-old quandary in quantum physics, paving the way for the development of new materials that could make electronic devices smaller and cars more energy efficient.

Quantum dots are man-made atoms that confine electrons to a small space. They have atomic-like behavior that results in unusual electronic properties on a nanoscale. These unique properties may be particularly valuable in tailoring the way light interacts with matter.

There are different types of ceramics, with technical ceramics being the group with the highest mechanical, electrical, and/or thermal properties. Its high productivity is partly due to its extremely high purity.

"The water content of leaves, their thickness, their density and other properties can now be determined without even having to touch them. A team of researchers from the CSIC Institute of Acoustics and the Agri-Food Research and Technology Centre (CITA) of Aragón has just presented an innovative technique that enables plant leaves to be studied using ultrasound in a quick, simple and non-invasive fashion."

"When the right microorganisms are at work, immune cells involved in the development of autoimmune illnesses like psoriasis, multiple sclerosis and arthritis, can develop anti-inflammatory properties. Scientists at Charité - Universitätsmedizin Berlin and the Institute for Research in Biomedicine, Bellinzona, Switzerland, have now made this discovery. Their work is published in the current issue of the scientific journal Nature*. The scientists were able to prove that particular fungi activate the immune cells involved in the development of certain illnesses, whereas other microorganisms, in particular bacteria that are found naturally on our skin, lend an anti-inflammatory function to them. "This not only demonstrates that the composition of our microflora has a decisive role in the development of chronic illnesses, but also that the key cells causing illness can develop an anti-inflammatory 'twin'," explained Dr. Christina Zielinski, first author of the study."

Open Economics Working Group is run by the Open Knowledge Foundation in association with the Centre for Intellectual and Property Law (CIPIL) at the University of Cambridge. Its membership consists of leading academics and researchers, public and private sector economists, representatives from national and international public bodies and other experts from around the world.

"Understanding the relationship between diversity and stability requires a knowledge of how species interact with each other and how each is affected by the environment. The relationship is also complex, because the concept of stability is multifaceted; different types of stability describing different properties of ecosystems lead to multiple diversity-stability relationships. A growing number of empirical studies demonstrate positive diversity-stability relationships. These studies, however, have emphasized only a few types of stability, and they rarely uncover the mechanisms responsible for stability. Because anthropogenic changes often affect stability and diversity simultaneously, diversity-stability relationships cannot be understood outside the context of the environmental drivers affecting both. This shifts attention away from diversity-stability relationships toward the multiple factors, including diversity, that dictate the stability of ecosystems."

"(PhysOrg.com) -- "Carbon nanotubes have a lot of really nice properties that make them good for photonics," Laurent Vivien tells PhysOrg.com. Ever since the discovery that carbon nanotubes have photoluminescence when encapsulated in micelle surfactant, Vivien points out, there has been interest in pursuing them for use in nanophotonics, and in microelectronics. "

"A group of researchers have developed what are known as vortex beams - rotating electron beams - which make it possible to investigate the magnetic properties of materials and in the future it may be possible to manipulate the tiniest components in a targeted manner and set them in rotation also."

WHAT do earthquakes, spinning stellar remnants, bright space objects and a host of other natural phenomena have in common? Some of their properties conform to a curious and little known mathematical law, which could now find new uses.

Fermilab physicists are examining the production, properties, and decay of top quarks to gain the most complete picture of the particle possible. They compare their observations to predictions made in the Standard Model of physics and in theories that build on that model.

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.

ScienceDaily (June 21, 2011) - An important milestone in the direct measurement of the magnetic moment of the proton and its anti-particle has been achieved.

The magnetic properties of Indole moieties

Material scientists were one of the oldest engineers. The earliest inventors had helped defining material science research, by discovering the properties and implementing one of the most important materials in the history of the world; 'METAL'. Metallurgy may not be entirely material science.

Advanced materials researches are done through The Trivedi Effect. The phenomenon has changed the physical properties of many materials.