More proof about diamonds around QC.
Creation of impossibly thin wires just three atoms wide opens up new possibilities in a variety of fields.
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Category: particle physics – Page 614
Testing Predictions of the Quantum Landscape Multiverse 2: The Exponential Inflationary Potential [CEA]
The 2015 Planck data release tightened the region of the allowed inflationary models. Inflationary models with convex potentials have now been ruled out since they produce a large tensor to scalar ratio. Meanwhile the same data offers interesting hints on possible deviations from the standard picture of CMB perturbations. Here we revisit the predictions of the theory of the origin of the universe from the landscape multiverse for the case of exponential inflation, for two reasons: firstly to check the status of the anomalies associated with this theory, in the light of the recent Planck data; secondly, to search for a counterexample whereby new physics modifications may bring convex inflationary potentials, thought to have been ruled out, back into the region of potentials allowed by data. Using the exponential inflation as an example of convex potentials, we find that the answer to both tests is positive: modifications to the perturbation spectrum and to the Newtonian potential of the universe originating from the quantum entanglement, bring the exponential potential, back within the allowed region of current data; and, the series of anomalies previously predicted in this theory, is still in good agreement with current data. Hence our finding for this convex potential comes at the price of allowing for additional thermal relic particles, equivalently dark radiation, in the early universe.
E. Valentino and L. Mersini-Houghton Wed, 28 Dec 16 26/46.
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Physicists Achieve Quantum Teleportation of Photon Over 25 Kilometers
For the first time, a team of physicists have successfully teleported a quantum state of a photon to a crystal over 25 kilometers away through a fiber optic cable. This effectively showed that the photon’s quantum state, not its composition, is important to the teleportation process. The team was led by Nicolas Gisin of the University of Geneva and the results were published in the journal Nature Photonics. With this new paper, Gisin’s team has successfully squashed the previous record they set a decade ago by teleporting a quantum state of a proton 6 kilometers.
The quantum state of the photon is able to preserve information under extreme conditions, including the difference between traveling as light or becoming stored in the crystal like matter. The photon’s state acts as information that can be teleported along great distances using the optical fiber, and can be stored within the crystal. This was achieved due to a phenomenon in quantum mechanics known as entanglement, where two particles have a correlation, despite the fact that they aren’t touching and transmitting information to one another.
To test this and ensure what they were observing was actually happening, one photon was stored in a crystal while the other was sent along optical fiber, over a distance of 25 kilometers. The photon that was sent along the optical fiber collides with a third photon, which was assumed to destroy them both. However, the information from the first photon was transferred to the third photon in the collision, like the transfer of energy when one billiard ball hits another. The information from the third photon came back to the crystal where it could be measured to ensure the information was preserved between the first and the second.
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The Edge of Physics: Do Gravitons Really Exist?
Einstein’s theory of relativity described gravity as the distortion of space and time—which bend and stretch based on the masses of objects within them as well as the energy released from the phenomena. A few years later however, we gained awareness of the confusing world of quantum physics as physicists discovered the existence of very small particles—which were later found to affect even the biggest, most powerful phenomena in the universe.
This led to the discovery of force-carrier particles, or bosons, behind three of the fundamental forces governing the universe: the electromagnetic field has photons, the strong nuclear force has gluons, and the weak force is carried by W and Z bosons. This leaves gravity out. Physicists hypothesize that, if the other three fundamental forces have a corresponding quantum theory, there must be a particle behind gravity too.
In an attempt to marry gravity with quantum theory, physicists came up with a hypothetical particle—the graviton. The graviton is said to be a massless, stable, spin-2 particle that travels at the speed of light.
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Jülich Installs New QPACE3 Supercomputer for Quantum Chromodynamics
A new supercomputer has been deployed at the Jülich Supercomputing Center (JSC) in Germany. Called QPACE3, the new 447 Teraflop machine is named for “QCD Parallel Computing on the Cell.”
QPACE3 is being used by the University of Regensburg for a joint research project with the University of Wuppertal and the Jülich Supercomputing Center for numerical simulations of quantum chromodynamics (QCD), which is one of the fundamental theories of elementary particle physics. Such simulations serve, among other things, to understand the state of the universe shortly after the Big Bang, for which a very high computing power is required.
The demand for high performance computers to solve complex applications has risen exponentially, but unfortunately so has their consumption of power. Many supercomputers require more than a megawatt of electricity to operate and annual electricity costs can easily run into millions of Euros. The energy supply is therefore a significant part of the operating costs of a data center. According to recent analyst studies, this represents the second-largest factor in addition to personnel and maintenance costs. The upcoming boom with (3D) video streaming, augmented reality, image recognition and artificial intelligence is driving up the demand for data center capabilities, thereby placing new challenges in the power supply sector.
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NASA Goddard: “All Galaxies are Embedded Within a Vast Sphere of Black Holes” (Holiday Feature)
Dark matter is a mysterious substance composing most of the material universe, now widely thought to be some form of massive exotic particle. An intriguing alternative view is that dark matter is made of black holes formed during the first second of our universe’s existence, known as primordial black holes.
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The world’s first demonstration of spintronics-based artificial intelligence
Excellent.
Researchers at Tohoku University have, for the first time, successfully demonstrated the basic operation of spintronics-based artificial intelligence.
Artificial intelligence, which emulates the information processing function of the brain that can quickly execute complex and complicated tasks such as image recognition and weather prediction, has attracted growing attention and has already been partly put to practical use.
The currently-used artificial intelligence works on the conventional framework of semiconductor-based integrated circuit technology. However, this lacks the compactness and low-power feature of the human brain. To overcome this challenge, the implementation of a single solid-state device that plays the role of a synapse is highly promising.
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Electron-photon small-talk could have big impact on quantum computing
In a step that brings silicon-based quantum computers closer to reality, researchers at Princeton University have built a device in which a single electron can pass its quantum information to a particle of light. The particle of light, or photon, can then act as a messenger to carry the information to other electrons, creating connections that form the circuits of a quantum computer.
The research, published in the journal Science and conducted at Princeton and HRL Laboratories in Malibu, California, represents a more than five-year effort to build a robust capability for an electron to talk to a photon, said Jason Petta, a Princeton professor of physics.
“Just like in human interactions, to have good communication a number of things need to work out—it helps to speak the same language and so forth,” Petta said. “We are able to bring the energy of the electronic state into resonance with the light particle, so that the two can talk to each other.”
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The perfect Christmas gift? A nanoscale snowman
Happy Holidays; happy end of the year, happy launch of next year, happy snow days, happy hot chocolate day, etc. Nonetheless, my gift to you this year is a Nanoscale Snowman.
Would a jewel-encrusted snowman make the perfect Christmas present? At only 5 nanometres in size, the price might be lower than you think. And it’s functional too, catalysing the splitting of water to make green hydrogen for fuel cells.
The nanoparticle, as imaged with the aberration-corrected scanning transmission electron microscopes, features eyes, nose and mouth of precious-metal platinum clusters embedded in a titanium dioxide face. Each platinum cluster typically contains 30 platinum atoms; within the whole nanoparticle there are approximately 1680 titanium atoms and 180 platinum atoms.
The nano-snowman formed spontaneously from a self-assembled platinum-titanium nanoparticle which was oxidised in air, drawing the titanium atoms out to the surface. The self-assembly occurred in a gas phase, cluster beam condensation source, before size-selection with a mass spectrometer and deposition onto a carbon surface for oxidation and then imaging. The mass of the snowman was 120,000 atomic mass units. Compared with a more conventional pure platinum catalyst particle, the inclusion of the titanium atoms offers two potential benefits: dilution of how much precious platinum is needed to perform the catalysis, and protection of the platinum cores against sintering (i.e. aggregation of the nanoparticles). The shell is porous enough to allow hydrogen through and the particles are functional in the hydrogen evolution reaction.
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