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Close encounters with medium-size black holes can reanimate dead stars, if only momentarily, a new study suggests. A team of astronomers performed computer simulations to determine what happens when a burned-out stellar corpse known as a white dwarf passes close to an intermediate-mass black hole — one that harbors between 1,000 and 10,000 times the mass of Earth's sun. The researchers determined that the black hole's powerful gravity can stretch and distort the white dwarf's previously inert innards so dramatically that nuclear-fusion processes can reignite for a few seconds, converting helium, carbon and oxygen into heavier elements such as iron....

In a marriage of quantum science and solid-state physics, researchers at the National Institute of Standards and Technology (NIST) have used magnetic fields to confine groups of electrons to a series of concentric rings within graphene, a single layer of tightly packed carbon atoms. This tiered "wedding cake," which appears in images that show the energy level structure of the electrons, experimentally confirms how electrons interact in a tightly confined space according to long-untested rules of quantum mechanics. The findings could also have practical applications in quantum computing. Graphene is a highly promising material for new electronic devices because of...

There's a sort of radio wave that bangs its way around Earth, knocking around electrons in the plasma fields of loose ions surrounding our planet and sending strange tones to radio detectors. It's called a "whistler." And now, scientists have observed bursts like this in more detail than ever before. Whistlers, typically created during certain lightning strikes, usually travel along Earth's magnetic-field lines. Humans first detected them more than a century ago, thanks to their ability to make a "whistling" sound (really more like a ghostly recording of laser blasts in a "Star Wars" movie) when picked up by a...

Up until last year, mathematician Peter Bierhorst had hoped the physicists he works with would fail. It was nothing personal. He just found their worldview a little disturbing. Like most physicists, his co-workers believe that our universe’s particles can influence each other using a sort of telepathy. Called “entanglement,” this connection allows two particles separated by vast distances to behave as a single entity. Both instantly react to something that happens to one of them. If you find this very weird and counterintuitive, you’re not alone. “I find this very weird and counterintuitive,” says Bierhorst, a postdoc at the National...

It's been nearly a century since scientists first theorized that the Universe was expanding, and that the farther away a galaxy was from us, the faster it appears to recede. This isn't because galaxies are physically moving away from us, but rather because the Universe is full of gravitationally-bound objects, and the fabric of space that those objects reside in is expanding. But this picture, which held sway from the 1920s onward, has been recently revised. It's been only 20 years since we first realized that this expansion was speeding up, and that as time goes on, individual galaxies will...

“Deep Space of the Cosmos” –There’s a Mysterious Energy Latent In It Which Can Tell Us About Our Fate  Posted on Aug 15, 2018 “Empty space seems to be nothing to us. By analogy, water may seem to be nothing to a fish – it’s what’s left when you take away all the other things floating in the sea. Likewise, empty space is conjectured to be quite complicated,” Martin Rees, Astronomer Royal and Emeritus Professor of Cosmology and Astrophysics at the University of Cambridge.Philosophers have debated the nature of “nothing” for thousands of years, but what has modern science got...

A supermassive black hole has been found at the center of a tiny galaxy, a rare find. What makes the discovery even more unique is that it has been located in an ultracompact dwarf galaxy, stunning researchers. The findings, published in the Monthly Notices of the Royal Astronomical Society, note that the galaxy Fornax UCD3 is part of a set called ultracompact dwarfs (UCDs), a very rare set of galaxies. "We have discovered a supermassive black hole in the center of Fornax UCD3," said the study's lead author, Anton Afanasiev, in a statement. "The black hole mass is 3.5 million...

Sound has negative mass, and all around you it's drifting up, up and away — albeit very slowly. That's the conclusion of a paper submitted on July 23 to the preprint journal arXiv, and it shatters the conventional understanding that researchers have long had of sound waves: as massless ripples that zip through matter, giving molecules a shove but ultimately balancing any forward or upward motion with an equal and opposite downward motion. That's a straightforward model that will explain the behavior of sound in most circumstances, but it's not quite true, the new paper argues. A phonon — a...

“Harnessing the mysterious property that Albert Einstein called ‘spooky action at a distance’ is a crucial step toward exploiting quantum quirks for technology such as new kinds of sensors or computers,” the physicists said. “Entanglement is not just some academic curiosity; it’s also something you can harness as a basis for doing useful things with quantum mechanics,” Professor Clerk added. Entangled states are typically extremely fragile — especially so when they involve large objects. So Professor Clerk and his colleague, Dr. Matt Woolley from the University of New South Wales, developed a theoretical proposal for how to keep the motion...

Next time you eat a blueberry (or chocolate chip) muffin consider what happened to the blueberries in the batter as it was baked. The blueberries started off all squished together, but as the muffin expanded they started to move away from each other. If you could sit on one blueberry you would see all the others moving away from you, but the same would be true for any blueberry you chose. In this sense galaxies are a lot like blueberries. Since the Big Bang, the universe has been expanding. The strange fact is that there is no single place from...

The knots in question, the researchers wrote in their paper, were visible enough in images of the light wave data for them to identify the figure eights and toruses. ... To create the knots, the researchers carefully tuned the up-and-down and side-to-side wave motion (the polarization) of two beams of light, partly using technology not unlike that found in polarized sunglasses. The knots formed around "polarization singularities" where the beams intersected, places where the side-to-side and up-and-down wavelengths were exactly equal, and a number of other wavelengths of light looped around them. At those points, light bent in the way...

The problem with string theory, according to some physicists, is that it makes too many universes. It predicts not one but some 10500 versions of spacetime, each with their own laws of physics. But with so many universes on the table, how can the theory explain why ours has the features it does? Now some theorists suggest most—if not all—of those universes are actually forbidden, at least if we want them to have stable dark energy, the supposed force accelerating the expansion of the cosmos. To some, eliminating so many possible universes is not a drawback but a major step...

New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.” “Octonions are to physics what the Sirens were to Ulysses,” Decades on, no particles beyond those of the Standard Model have been found. Meanwhile, the strange beauty of the octonions has continued to attract the occasional independent-minded researcher, including Furey, the Canadian grad student who visited Günaydin four years ago. Looking like an interplanetary traveler, with choppy silver bangs that taper to a point between piercing blue eyes, Furey scrawled esoteric symbols on a blackboard, trying to explain to Günaydin that...

Our universe's rate of expansion keeps getting stranger. New data continues to show a discrepancy in how fast the universe expands in nearby realms and more distant locations.  The study's researchers said this "tension" could mean we need to revise our understanding of the physics structuring the universe, which could include exotic elements such as dark matter and dark energy. New measurements from the Hubble Space Telescope and the Gaia space telescope together showed that the rate of expansion nearby is 45.6 miles per second per megaparsec. This means that for every 3.3 million light-years a galaxy is farther away from...

Do neutron stars contain exotic matter in the form of dense deconfined quark matter? Scientists performed the first accurate determination of the thermodynamic properties of dense quark matter under violent conditions that occur during neutron star mergers, and suggest a step towards distinguishing between neutron and quark matter cores in neutron stars. The recent detection of gravitational waves emitted by two merging black holes by the LIGO and Virgo collaborations has opened up a new observational window into the cosmos. Future observations of similar mergers between two neutron stars or a neutron star and a black hole may revolutionize what...

It will let researchers study distant energy sources across the universe in "a completely new way" SCIENTISTS have captured a ghost-like subatomic particle on Earth, helping to solve a mystery baffling scientists for 100 years. The so-called "ghost particle" was trapped by researchers in a giant ice cube at the South Pole. It's actually a high-energy neutrino, and is the first of its type ever detected by scientists. Importantly, researchers believe they've tracked its likely source: a supermassive black hole that emits light and cosmic rays. The black hole is roughly four billion light years away, at the centre of...

Today, workers at the world’s largest atom smasher are breaking ground on a performance-enhancing upgrade that will allow scientists to conduct even bigger and better physics experiments. The upgrade will turn the Large Hadron Collider in Geneva, Switzerland into the High-Luminosity Large Hadron Collider (HL-LHC). The upgrade will allow the machine to collide even more particles, potentially helping physicists see new stuff. “The HL-LHC will enable us to do many things, opening many unexplored areas of research,” Rebeca Gonzalez Suarez, a postdoc research associate at CERN, told Gizmodo in an email. The Large Hadron Collider is essentially two 16-mile-round rings...

Currently, the heaviest element on the periodic table is oganesson, which has an atomic mass of 294 and was officially named in 2016. Like every element on the periodic table, nearly all of oganesson's mass comes from protons and neutrons (types of baryons) that are themselves made of three quarks each. A crucial feature of all known baryonic matter is that its quarks are bound together so tightly by the strong force that they are inseparable. As particles made of bound quarks (such as protons and neutrons) are called hadrons, scientists refer to the ground state of baryonic matter as...

The Higgs field is like an endless ocean through which all matter swims. Some particles are like sponges and sop up mass as they lumber along, while others are as sprightly as tiny minnows and dart right through. … "We know that the Higgs interacts with massive force-carrying particles, like the W boson, because that's how we originally discovered it," said scientist Patty McBride ... "Now we're trying to understand its relationship with fermions." Fermions are particles that click together to form the invisible scaffolding inside atoms. Bosons, on the other hand, are the physical manifestation of forces and perform...

The Next Big Discovery in Astronomy? We Probably Found It Years Ago — But Don't Know It Yet By Eileen Meyer, University of Maryland, Baltimore County | June 3, 2018 08:44am ET MORE An artist's illustration of a black hole "eating" a star.Credit: NASA/JPL-Caltech This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. Earlier this year, astronomers stumbled upon a fascinating finding: Thousands of black holes likely exist near the center of our galaxy. The X-ray images that enabled this discovery weren't from some state-of-the-art new telescope. Nor were...