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Louisiana State University physicists have leveraged quantum information theory techniques to reveal a mechanism for amplifying, or "stimulating," the production of entanglement in the Hawking effect in a controlled manner. Furthermore, these scientists propose a protocol for testing this idea in the laboratory using artificially produced event horizons. These results have been recently published in Physical Review Letters, "Quantum aspects of stimulated Hawking radiation in an analog white-black hole pair," where Ivan Agullo, Anthony J. Brady and Dimitrios Kranas present these ideas and apply them to optical systems containing the analog of a pair white-black hole. Stephen Hawking added more...

In 2020 a team led by European Southern Observatory (ESO) astronomers reported the closest black hole to Earth, located just 1000 light-years away in the HR 6819 system. But the results of their study were contested by other researchers, including by an international team based at KU Leuven, Belgium. In a paper published today, these two teams have united to report that there is in fact no black hole in HR 6819, which is instead a “vampire” two-star system in a rare and short-lived stage of its evolution. The original study on HR 6819 received significant attention from both the...

NASA’S NEW SHORTCUT TO FUSION POWER Lattice confinement fusion eliminates massive magnets and powerful lasers PHYSICISTS FIRST SUSPECTED more than a century ago that the fusing of hydrogen into helium powers the sun. It took researchers many years to unravel the secrets by which lighter elements are smashed together into heavier ones inside stars, releasing energy in the process. And scientists and engineers have continued to study the sun’s fusion process in hopes of one day using nuclear fusion to generate heat or electricity. But the prospect of meeting our energy needs this way remains elusive. The extraction of energy...

FAYETTEVILLE, Ark. – A team of University of Arkansas physicists has successfully developed a circuit capable of capturing graphene's thermal motion and converting it into an electrical current. “An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,” said Paul Thibado, professor of physics and lead researcher in the discovery.The findings, titled "Fluctuation-induced current from freestanding graphene," and published in the journal Physical Review E, are proof of a theory the physicists developed at the U of A three years ago that freestanding graphene — a single...

Scientists at EPFL’s Swiss Plasma Center and DeepMind have jointly developed a new method for controlling plasma configurations for use in nuclear fusion research. EPFL’s Swiss Plasma Center (SPC) has decades of experience in plasma physics and plasma control methods. DeepMind is a scientific discovery company acquired by Google in 2014 that's committed to ‘solving intelligence to advance science and humanity. Together, they have developed a new magnetic control method for plasmas based on deep reinforcement learning, and applied it to a real-world plasma for the first time in the SPC’s tokamak research facility, TCV. Their study has just been...

A physics problem that has plagued science since the days of Isaac Newton is closer to being solved, say a pair of Israeli researchers. The duo used "the drunkard's walk" to calculate the outcome of a cosmic dance between three massive objects, or the so-called three-body problem. For physicists, predicting the motion of two massive objects, like a pair of stars, is a piece of cake. But when a third object enters the picture, the problem becomes unsolvable. That's because when two massive objects get close to each other, their gravitational attraction influences the paths they take in a way...

Microlensing strikes again. Astronomers have been using the technique to detect everything from rogue planets to the most distant star ever seen. Now, astronomers have officially found another elusive object that has long been theorized, and that Universe Today first reported on back in 2009 but has never directly detected – a rogue black hole. That detection comes at the end of a 6-year observational campaign, with dozens of authors collaborating on a paper recently published in arXiv (meaning it has not yet been peer-reviewed). Those six years of painstakingly gathered data all started back in 2011, when a star...

A few years ago, a novel measurement technique showed that protons are probably smaller than had been assumed since the 1990s. The discrepancy surprised the scientific community; some researchers even believed that the Standard Model of particle physics would have to be changed. Physicists at the University of Bonn and the Technical University of Darmstadt have now developed a method that allows them to analyze the results of older and more recent experiments much more comprehensively than before. This also results in a smaller proton radius from the older data. So there is probably no difference between the values -...

Cosmic physics mimicked on table-top as graphene enables Schwinger effect. Researchers at The University of Manchester have succeeded in observing the so-called Schwinger effect, an elusive process that normally occurs only in cosmic events. By applying high currents through specially designed graphene-based devices, the team — based at the National Graphene Institute — succeeded in producing particle-antiparticle pairs from a vacuum. A vacuum is assumed to be completely empty space, without any matter or elementary particles. However, it was predicted by Nobel laureate Julian Schwinger 70 years ago that intense electric or magnetic fields can break down the vacuum and...

The MWA's view of the sky; the object is marked with a white star. (Dr Natasha Hurley-Walker/ICRAR/Curtin and the GLEAM Team) Something in Earth's cosmic neighborhood is emitting weird signals of a kind we've never seen before. Just 4,000 light-years away, something is flashing radio waves. For roughly 30 to 60 seconds, every 18.18 minutes, it pulses brightly, one of the most luminous objects in the low-frequency radio sky. It matches the profile of no known astronomical object, and astronomers are gobsmacked. They have named it GLEAM-X J162759.5-523504.3. "This object was appearing and disappearing over a few hours during our...

In a quest to map out a quantum theory of gravity, researchers have used logical rules to calculate how much Einstein’s theory must change. The result matches string theory perfectly. 4 ========================================================================== Quantum gravity researchers use α to denote the size of the biggest quantum correction to Einstein’s general relativity. Recently, three physicists calculated a number pertaining to the quantum nature of gravity. When they saw the value, “we couldn’t believe it,” said Pedro Vieira, one of the three. Gravity’s quantum-scale details are not something physicists usually know how to quantify, but the trio attacked the problem using an approach...

A visualization of the zero-energy electronic states – also known as a ‘Fermi surface’ – from the kagome material studied by MIT’s Riccardo Comin and colleagues. Credit: Comin Laboratory, MIT ************************************************************************** Work will aid design of other unusual quantum materials with many potential applications. MIT physicists and colleagues have discovered the “secret sauce” behind some of the exotic properties of a new quantum material that has transfixed physicists due to those properties, which include superconductivity. Although theorists had predicted the reason for the unusual properties of the material, known as a kagome metal, this is the first time that the...

Quantum batteries could one day revolutionize energy storage through what seems like a paradox – the bigger the battery, the faster it charges. For the first time, a team of scientists has now demonstrated the quantum mechanical principle of superabsorption that underpins quantum batteries in a proof-of-concept device. The quirky world of quantum physics is full of phenomena that seem impossible to us. Molecules, for instance, can be become so entwined that they begin acting collectively, and this can lead to a range of quantum effects. That includes superabsorption, which boosts a molecule’s ability to absorb light. “Superabsorption is a...

The supermassive black hole at the center of the Milky Way, Sagittarius A*, keeps releasing random bursts of radiation on a daily basis and no one can figure out what is causing it. These bursts ranged from tens to hundreds of times brighter than the normal signals sent out by the supermassive black hole at the heart of our galaxy, but they don't appear to follow a discernable pattern. The data from 2006 to 2008 show high levels of gamma-ray activity, followed by a rapid four-year-long drop, after which activity shot back up, starting in 2012. There could be any...

A new discovery could help scientists to understand “strange metals,” a class of materials that are related to high-temperature superconductors and share fundamental quantum attributes with black holes. Scientists understand quite well how temperature affects electrical conductance in most everyday metals like copper or silver. But in recent years, researchers have turned their attention to a class of materials that do not seem to follow the traditional electrical rules. Understanding these so-called “strange metals” could provide fundamental insights into the quantum world, and potentially help scientists understand strange phenomena like high-temperature superconductivity. Now, a research team co-led by a Brown...

The underlying theory is simple enough. "If you can get electrons to pair, they can superconduct," said Dean. According to the Bardeen-Cooper-Schrieffer (BCS) theory, an attractive force between electrons—no matter how weak—will cause those electrons to pair up and form a new kind of particle called a "Cooper pair." These behave like particles called bosons and, at low enough temperatures, can enter into a collective state and move through a material unimpeded by disorder—a feature any single electron just cannot achieve on its own. But there's been a problem. "Electrons do not want to pair," said Dean. Like repels like,...

Physicists at the U.S. Department of Energy's Princeton Plasma Physics Laboratory, working with Japanese researchers, made the observation on the Large Helical Device (LHD) in Japan, a twisty magnetic facility that the Japanese call a "heliotron." The results demonstrated for the first time a novel regime for confining heat in facilities known as stellarators, similar to the heliotron. The findings could advance the twisty design as a blueprint for future fusion power plants Researchers produced the higher confinement regime by injecting tiny grains of boron powder into the LHD plasma that fuels fusion reactions. The injection through a PPPL-installed dropper...

Scientists have found that antimatter particles fall down, not up, just like regular matter... Physicists at CERN have discovered that antimatter falls down. Sure, it sounds like an obvious thing, but scientists haven’t yet been able to confirm that it responds to gravity in exactly the same way as regular matter does. A new experiment provides the best answer so far. Antimatter is much like the matter that makes up everything around us, with one important difference: its particles have the opposite electric charge. And that simple difference has some major implications – whenever a particle and its antiparticle meet,...

"Using two Hawaiʻi telescopes—the University of Hawaiʻi Institute for Astronomy Pan-STARRS on Haleakalā, Maui and W. M. Keck Observatory on Maunakea, Hawaiʻi Island—a team of researchers conducting the Young Supernova Experiment (YSE) transient survey observed the red supergiant during its last 130 days leading up to its deadly detonation."

For years, experts thought the biggest stars in the universe, red supergiants, died with a whimper. But in 2020, astronomers witnessed quite the opposite. One of these gleaming monsters -- 10 times more massive than the sun -- violently self-destructed after presenting the cosmos with a final, radiant beacon of starlight. ..Jacobson-Galán is the lead author of a paper published Thursday in The Astrophysical Journal that documents the star's eruption as well as its last, 130-day hurrah.... ...The star's extreme illumination indicated it wasn't dormant, or quiescent, as previously observed red supergiants had been prior to their demise. This shiny...