The most fundamental limitations of modern physics might not be so limiting after all.
Category: physics – Page 348
Magnetic Hyperbolic Optical Metamaterial Could Advance Thermophotovoltaics
Improving energy efficiencies — nice.
The remarkable properties researchers at the Australian National University (ARC Centre of Excellence CUDOS) and the University of California Berkeley have discovered in a new nano-metamaterial could lead to highly efficient thermophotovoltaic cells. The new artificial material glows in an unusual way when headed.
As shown in the image, the metamaterial comprises 20 stacked alternating layers of 30-nm-thick gold and 45-nm-thick magnesium fluoride dielectric, perforated with 260 × 530 nm holes that are arranged into a 750 × 750 nm square lattice.
Thermophotovoltaics typically use a heated object as a source of radiation that is then converted to electricity by a photovoltaic cell. The caveat is that heated object emits light in all directions and over a broad spectral region, which reduces the efficiency of the light-to-electricity conversion. However, “The demonstrated metamaterial emits thermal radiation predominantly in particular directions and [within] a particular spectral region, which could make the conversion more efficient,” says Dr Sergey Kruk at the Nonlinear Physics Centre in the ANU Research School of Physics and Engineering.
Researchers teach AI system to run complex physics experiment
ACTON, Australia, May 16 (UPI) — A pair of physicists in Australia have trained an artificial intelligence system to replicate the experiment that won the 2001 Nobel Prize.
The experiment involves what is known as a Bose-Einstein condensate, the trapping of an ultra-cool gas in a series of lasers.
At just a billionth of a degree above absolute zero, Bose-Einstein condensates constitute some of the coldest temperatures in the universe — colder than interstellar space.
Wormholes could be the key to beating the Heisenberg’s uncertainty principle, say physicists
Time travel seems much more common in science fiction than it is in reality. We’ve never met anyone from the future, after all. But all of the physics we know indicates that wormholes — another science fiction favourite — could really be used to travel backwards in time.
And according to a paper by Chinese physicists, using wormholes for time travel might actually allow us to beat Heisenberg’s uncertainty principle — described as one of the most famous (and probably misunderstood) ideas in physics — and even to solve some of the most difficult problems in computer science.
Wormholes are like portals between two places in the Universe. If you fell in one side, you’d pop out the other immediately, regardless of how far apart the two sides were. But wormholes are also like portals between two times in the Universe. As Carl Sagan liked to say, you wouldn’t just emerge some where else in space, but also some when else in time.
Physics Experiments Take Images ‘Back in Time’
BLOOMINGTON, Ill.— An international team of physicists including Illinois Wesleyan University Professor of Physics Gabe Spalding has shown waves of light can seem to travel back in time.
It may seem like science fiction, but the experiment did not violate the laws of physics. Spalding, his physics student Joseph Richards ’16 and a team of scientists tackled a century-old intuition from Lord Rayleigh regarding the speed of sound. Rayleigh theorized that music being played on an object traveling faster than the speed of sound, a supersonic jet for example, would result in a listener hearing the music playing in reverse. The Spalding team simulated what an observer standing still would see when looking at a superluminal (faster than the speed of light) occurrence. The results of the scientists’ experiment, conducted last summer at Heriot-Watt University in Edinburgh, Scotland, have been published in Science Advances.
“The existence of an absolute limit, the speed of light, is the natural source of the question: what would happen if we cross this limit?” lead author Mattero Clerici told a writer for a post on IFLScience. “Light sources, however, may move faster than the speed of light when their speed is not associated with the physical motion of matter. Following this line of thought, we devised a way to experimentally investigate the [effects] of superluminal motion.”
Tiny Tests Probe for Dark Matter and Other Exotic Physics
Experiments that can fit on a tabletop are probing the nature of dark matter and dark energy and searching for evidence of extra dimensions.
Unique nano-capsules promise the targeted drug delivery
Gotta luv this.
An international team of researchers including the Lomonosov Moscow State University physicists has developed a completely new type of drug carrier for targeted delivery to the sick organ — the gel nano-capsules with a double shell. The results of the study were published in Scientific Reports.