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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...

An artist’s impression of a red supergiant star in the final year of its life emitting a tumultuous cloud of gas. This suggests at least some of these stars undergo significant internal changes before going supernova. Credit: W.M. Keck Observatory/Adam Makarenko Astronomers Capture Red Supergiant’s Death Throes “For the first time, we watched a red supergiant star explode,” researcher says. For the first time ever, astronomers have imaged in real time the dramatic end to a red supergiant’s life — watching the massive star’s rapid self-destruction and final death throes before collapsing into a type II supernova. Led by researchers...

Particles forming swirling, tornado-like structures. (Mukherjee et al, Nature, 2022 ============================================================================== Scientists have observed a stunning demonstration of classic physics giving way to quantum behavior, manipulating a fluid of ultra-cold sodium atoms into a distinct tornado-like formation. Particles behave differently on the quantum level, in part because at this point their interactions with each other hold more power over them than the energy from their movement. Then, of course, there's the mind-boggling fact that quantum particles don't exactly have a certain fixed location like you or I, which influences how they interact. By cooling particles down to as close to...

This animation shows an artist’s rendition of the cloudy structure revealed by a study of data from NASA’s Rossi X-Ray Timing Explorer satellite. Credit: Wolfgang Steffen, UNAM ======================================================================== Upending textbook explanations, astrophysicists from the University of Miami, Yale University, and the European Space Agency suggest that primordial black holes account for all dark matter in the universe. Proposing an alternative model for how the universe came to be, a team of astrophysicists suggests that all black holes—from those as tiny as a pinhead to those covering billions of miles—were created instantly after the Big Bang and account for all dark...

(LOFAR/LOL Survey) The image above may look like a fairly normal picture of the night sky, but what you're looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole. And each of those black holes is devouring material at the heart of a galaxy millions of light-years away – that's how they could be pinpointed at all. Totaling 25,000 such dots, astronomers created the most detailed map to date of black holes at low radio frequencies in early 2021, an achievement that took years and a Europe-sized radio...

The researchers created the tiny transistor by simultaneously applying a force and low voltage which heated a carbon nanotube made up of few layers until outer tube shells separate, leaving just a single-layer nanotube. The heat and strain then changed the "chilarity" of the nanotube, meaning the pattern in which the carbon atoms joined together to form the single-atomic layer of the nanotube wall was rearranged. The result of the new structure connecting the carbon atoms was that the nanotube was transformed into a transistor. Professor Golberg's team members from the National University of Science and Technology in Moscow created...

Imaginary numbers are necessary to accurately describe reality, two new studies have suggested. Imaginary numbers are what you get when you take the square root of a negative number, and they have long been used in the most important equations of quantum mechanics, the branch of physics that describes the world of the very small. When you add imaginary numbers and real numbers, the two form complex numbers, which enable physicists to write out quantum equations in simple terms. But whether quantum theory needs these mathematical chimeras or just uses them as convenient shortcuts has long been controversial. In fact,...

Illustration of the double pulsar PSR J0737−3039A/B. (Michael Kramer/MPIfRA) Two pulsars locked in close binary orbit have once again validated predictions made by Einstein's theory of general relativity. Over 16 years, an international team of astronomers has observed the pulsar pair, named PSR J0737−3039A/B, finding that the relativistic effects can be measured in the timing of their pulses – just as predicted and expected. This is the first time these effects have been observed. "We studied a system of compact stars that is an unrivalled laboratory to test gravity theories in the presence of very strong gravitational fields," says astronomer...