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Sep 13, 2016

Quantum Cosmology and the Evolution of Inflationary Spectra [CL]

Posted by in categories: cosmology, evolution, information science, quantum physics

We illustrate how it is possible to calculate the quantum gravitational effects on the spectra of primordial scalar/tensor perturbations starting from the canonical, Wheeler-De Witt, approach to quantum cosmology. The composite matter-gravity system is analysed through a Born-Oppenheimer approach in which gravitation is associated with the heavy degrees of freedom and matter (here represented by a scalar field) with the light ones. Once the independent degrees of freedom are identified the system is canonically quantised. The differential equation governing the dynamics of the primordial spectra with its quantum-gravitational corrections is then obtained and is applied to diverse inflationary evolutions. Finally, the analytical results are compared to observations through a Monte Carlo Markov Chain technique and an estimate of the free parameters of our approach is finally presented and the results obtained are compared with previous ones.

Read this paper on arXiv…

A. Kamenshchik, A. Tronconi and G. Venturi Tue, 13 Sep 16 11/91.

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Sep 13, 2016

The Military Wants A Way To Track Drones Flying Over Cities

Posted by in categories: drones, military

About time.


Who watches the drones? Other drones.

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Sep 13, 2016

Worm holes- the sad existence of a path impossible to travel

Posted by in category: cosmology

The existence of worms holes has been long debated and has even become a staple in science fiction.

( source )

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Sep 13, 2016

New Laser Provides Ultra-Precise Tool for Scientists Probing the Secrets of the Universe

Posted by in categories: particle physics, quantum physics, space

WASHINGTON — Researchers have developed a new laser that makes it possible to measure electron transition energies in small atoms and molecules with unprecedented precision. The instrument will help scientists test one of the bedrock theories of modern physics to new limits, and may help resolve an unexplained discrepancy in measurements of the size of the proton.

The team will present their work during the Frontiers in Optics (FiO) / Laser Science (LS) conference in Rochester, New York, USA on 17 −21 October 2016.

“Our target is the best tested theory there is: quantum electrodynamics,” said Kjeld Eikema, a physicist at Vrije University, The Netherlands, who led the team that built the laser. Quantum electrodynamics, or QED, was developed in the 1940s to make sense of small unexplained deviations in the measured structure of atomic hydrogen. The theory describes how light and matter interact, including the effect of ghostly ‘virtual particles.’ Its predictions have been rigorously tested and are remarkably accurate, but like extremely dedicated quality control officers, physicists keep ordering new tests, hoping to find new insights lurking in the experimentally hard-to-reach regions where the theory may yet break down.

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Sep 13, 2016

Lighting the way to miniature devices

Posted by in categories: computing, engineering, quantum physics

Electromagnetic waves created on a layer of organic molecules could provide the perfect on-chip light source for future quantum communication systems.

A team of scientists including researchers at Agency for Science, Technology and Research (A*STAR), Singapore, has captured tiny flashes of light from an ultrathin layer of organic molecules sandwiched between two electrodes that could replace lasers and LEDs as signal sources for future miniature, ultrafast quantum computing and light-based communication systems.

To investigate electromagnetic waves called plasmons, which skim along the interface between two materials, Nikodem Tomczak from the A*STAR Institute of Materials Research and Engineering and colleagues collaborated with Christian A. Nijhuis from the National University of Singapore to construct a junction consisting of a layer of thiol molecules on a metal electrode and liquid gallium-indium alloy as a top electrode.

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Sep 13, 2016

Fear Of Russia Drives Sweden Closer To NATO

Posted by in categories: government, policy

Wow; Europe is growing more nervous.


WASHINGTON: The Russian threat has driven Sweden so close to NATO that the once-neutral nation is becoming an ally in all but name. While the current Swedish government won’t apply for NATO membership — a position it just reiterated Friday — every other kind of collaboration is not only on the table, but actually happening more and more.

Recent agreements are bringing Sweden into NATO policy councils and wargame planning in unprecedented ways. Sweden is building up its forces to keep an ever closer watch on Russia both in the Arctic and the Baltic. A Host Nation Agreement — signed just months after Russia’s annexation of Crimea — makes it easier for NATO to operate in Swedish territory (if invited). Sweden has even sent troops to Afghanistan. With friends like these, who needs formal allies?

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Sep 13, 2016

Putin once casually said over dinner that he could destroy America in a half-hour or less

Posted by in category: futurism

Hmmmm;


In December 2011, Vladimir Putin, then Russia’s prime minister, was positioned to reclaim his role as Russia’s president in the March 2012 elections.

Fittingly, he hosted a lavish banquet at New Century, Moscow’s richest equestrian club, for members of the Valdai Club and distinguished academics and journalists from around the world.

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Sep 13, 2016

Early cancer detection: Russian researchers on verge of breakthrough

Posted by in categories: biotech/medical, nanotechnology

TheTribune: NEW DELHI: Russian researchers have developed a nanotechnology tool for early diagnosis of cancer and are planning to launch clinical trials of the product in 2018.

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Sep 13, 2016

Benchtop Black Holes Help Physicists Glimpse the Quantum Universe

Posted by in categories: cosmology, particle physics, quantum physics

A black hole is a physicist’s playground: A place where some of the most bizarre and fundamental concepts in physics can be observed and tested. However, there is currently no way to directly observe black holes in action; these bodies of matter don’t emit the sort of radiation, like light or X-rays, that telescopes are equipped to detect. Fortunately, physicists have figured out ways to imitate the conditions of a black hole in the lab—and in creating analogues of black holes, they are beginning to unravel some the most fascinating puzzles in physics.

Jeff Steinhauer, a researcher in the Physics Department of Technion-Israel Institute of Technology, recently caught the attention of the physics community when he announced that he had used an analogue black hole to confirm Stephen Hawking’s 1974 theory that black holes emit electromagnetic radiation, known as Hawking radiation. Hawking predicted that this radiation would be caused by the spontaneous creation of a particle-antiparticle pair at the event horizon, the point at the edge of a black hole beyond which nothing—not even light—can escape. Under the terms of Hawking’s theory, as one of the particles crosses the event horizon and is captured by the black hole, the other would be ejected into space. Steinhauer’s experiment was the first to exhibit the sort of spontaneous fluctuations that support Hawking’s calculations.

Physicists have cautioned that this experiment still doesn’t confirm the existence of Hawking radiation in astronomical black holes, as Steinhauer’s black hole isn’t exactly the same as one we might observe in space. It’s not yet physically possible to create the intense gravitational fields that form black holes. Instead, the analogue imitates a black hole’s ability to absorb light waves by using sound.

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Sep 13, 2016

Effects of Band Nonparabolicity and Band Offset on the Electron Gas Properties in InAs/AlSb Quantum Well

Posted by in categories: energy, quantum physics

One-band effective mass model is used to simulation of electron gas properties in quantum well. We calculate of dispersion curves for first three subbands. Calculation results of Fermi energy, effective mass at Fermi level as function of electron concentration are presented. The obtained results are good agreement with the experimental dates.

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