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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...

Explanation: Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and why visible matter is distributed as it is both in the local universe and on the cosmic microwave background. The featured image from the American Museum of Natural History's Hayden Planetarium Space Show Dark Universe highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer simulation,...

Dark energy, a mysterious force believed to be causing the universe to expand at an accelerated rate, may have been detected by scientists for the first time. In a new study, published Wednesday in the journal Physical Review D, the authors suggest certain unexplained results from an experiment designed to detect dark matter could have been caused by dark energy. "Despite both components being invisible, we know a lot more about dark matter, since its existence was suggested as early as the 1920s, while dark energy wasn’t discovered until 1998," Sunny Vagnozzi, of the University of Cambridge’s Kavli Institute for...

Using a technique called pendellösung interferometry, a team of physicists...have used neutron beams to probe the crystal structure of silicon at the highest precision yet achieved... This has revealed previously unrecognized properties in silicon, a material crucial to technology; more detailed information about the properties of the neutron; and placed important constraints on the fifth force, if it exists. In a perfect silicon crystal, sheets of atoms in the lattice are arranged in planes that repeat in spacing and orientation. Bouncing the beam precisely off these planes can cause the neutrons to diverge in their routes through the lattice, generating...

The galactic plane, seen through infrared eyes. (NASA/JPL-Caltech/UCLA) ______________________________________________________________________________________ There are many kinds of stars out there in the big, wide Universe. We have a whole system for categorizing them according to temperature, size, and brightness. Even so, a recently discovered object is suggesting that we're far from knowing everything. It's been nicknamed 'The Accident', and it's a type of object called a brown dwarf, also known as failed stars. But it's unlike any brown dwarf we've ever seen before, with a confusing spectrum – suggesting that it may be nearly as old as the Universe. Since all of the...

Polarized view of the black hole in M87. The lines mark the orientation of polarization, which is related to the magnetic field around the shadow of the black hole. Credit: EHT Collaboration ===================================================================== Wits University astrophysicists are the only two scientists on African continent that contributed to the study. The Event Horizon Telescope (EHT) collaboration, a multinational team of over 300 scientists including two astrophysicists from the University of the Witwatersrand (Wits University), has revealed a new view of the massive object at the center of the M87 galaxy: how it looks in polarized light. This is the first time...

The new explosion, illustrated here, is bluer than an ordinary supernova and more than 100 times as bright. SAKKMESTERKE / Science Source =================================================================== A supernova-like explosion dubbed the Camel appears to be the result of a newborn black hole eating a star from the inside out. ================================================================ In 2018, astronomers were shocked to find a bizarre explosion in a galaxy 200 million light-years away. It wasn’t like any normal supernova seen before — it was both briefer and brighter. The event was given an official designation, AT2018cow, but soon went by a more jovial nickname: the Cow. The short-lived event...

They may not be black or holes. Some astronomers believe there is a massive planet, far beyond the orbit of Neptune, orbiting the sun — but after years of searching, scientists have not found this theoretical world, which they've dubbed "Planet Nine." This has spurred theorists to consider a radical hypothesis: Perhaps Planet Nine is not a planet but rather a small black hole that might be detectable from the theoretical radiation emitted from its edge, so-called Hawking radiation. For centuries, astronomers have used variations in planetary orbits to predict the existence of new planets. When a planet's orbit doesn't...

Observations of galactic rotation curves give one of the strongest lines of evidence pointing towards the existence of dark matter, a non-baryonic form of matter that makes up an estimated 85% of the matter in the observable Universe. Current assessments of galactic rotation curves are based upon a framework of Newtonian accounts of gravity, a new article suggests that if this is substituted with a general relativity-based model, the need to recourse to dark matter is relieved, replaced by the effects of gravitomagnetism.

Researchers used the ALMA telescope array in Chile to discover the quasar A quasar is a type of supermassive black hole that is releasing a lot of energy This object was discovered when the universe was just 670 million years old The discovery can help researchers better understand how these objects form Its age and size brings into doubt theories they were formed from collapsed star clusters, with researchers suggesting they instead feast on cold hydrogen gas =========================================================== The most distant supermassive black hole known to science has been detected by astronomers - and it is more than 13 billion...

The largest black holes in the universe... sit at the centers of almost every galaxy in the cosmos. Even the Milky Way has one, a monster at 4 million solar masses, designated as Sagittarius A*. ...[A]s far as we know, the only way to form black holes is through the deaths of massive stars. When they die, they leave behind a black hole a few times more massive than the sun. To get to supergiant status, they have to merge with other black holes and/or consume as much gas as possible, bulking up all those millions of solar masses... Either...

Artist's impression of a galaxy surrounded by gravitational distortions due to dark matter. Galaxies live inside larger concentrations of invisible dark matter (coloured purple in this image), however the dark matter's effects can be seen by looking at the deformations of background galaxies. Credit: Swinburne Astronomy Productions - James Josephides ========================================================================== A small team of astronomers have found a new way to 'see' the elusive dark matter haloes that surround galaxies, with a new technique 10 times more precise than the previous-best method. The work is published in Monthly Notices of the Royal Astronomical Society. Scientists currently estimate that up...

......................................And that led to a remarkable twist in the story. Because the radiation is highly entangled with the black hole it came from, the quantum computer, too, becomes highly entangled with the hole. Within the simulation, the entanglement translates into a geometric link between the simulated black hole and the original. Put simply, the two are connected by a wormhole. “There’s the physical black hole and then there’s the simulated one in the quantum computer, and there can be a replica wormhole connecting those,” said Douglas Stanford, a theoretical physicist at Stanford and a member of the West Coast team....

Explanation: Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and why visible matter is distributed as it is both in the local universe and on the cosmic microwave background. The featured image from the American Museum of Natural History's Hayden Planetarium previous Space Show Dark Universe highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer...

Roger Penrose’s theoretical work demonstrated the objects could form. Reinhard Genzel and Andrea Ghez independently discovered a supermassive one at the center of the Milky Way. Roger Penrose, Reinhard Genzel, and Andrea Ghez are to be awarded the 2020 Nobel Prize in Physics for their theoretical and observational work on black holes, the Royal Swedish Academy of Sciences announced on Tuesday. Penrose will receive half the 10 million Swedish krona (roughly $1.1 million) prize; Ghez and Genzel will share the other half. Penrose, of the University of Oxford, helped place the previously idealized concept of a black hole on sound...

Image and amplification (in color) of the ultra-diffuse galaxy Dragonfly 44 taken with the Hubble space telescope. Credit: Teymoor Saifollahi and NASA/HST. ============================================================================= At present, the formation of galaxies is difficult to understand without the presence of a ubiquitous, but mysterious component, termed dark matter. Astronomers have measure how much dark matter there is around galaxies, and have found that it varies between 10 and 300 times the quantity of visible matter. However, a few years ago, the discovery of a very diffuse object, named Dragonfly 44, changed this view. It was found that this galaxy has 10,000 times more...

It would be extremely optimistic to suggest that we have a good handle on dark matter. But even the slight grasp we do have may be missing something important. New observations from the Hubble Space Telescope have found much higher concentrations of dark matter than expected in some galaxies, by over an order of magnitude. These concentrations are inconsistent with theoretical models, suggesting that there's a big gap in our understanding - the simulations could be incorrect, or there could be a property of dark matter we don't fully understand, according to the research team. "We have done a lot...

Explanation: How do black holes like this form? The two black holes that spiraled together to produce the gravitational wave event GW190521 were not only the most massive black holes ever seen by LIGO and VIRGO so far, their masses -- 66 and 85 solar masses -- were unprecedented and unexpected. Lower mass black holes, below about 65 solar masses are known to form in supernova explosions. Conversely, higher mass black holes, above about 135 solar masses, are thought to be created by very massive stars imploding after they use up their weight-bearing nuclear-fusion-producing elements. How such intermediate mass black...

The information locked inside black holes could be detected by feeling their 'hair,' new research suggests. As far as we understand them (which, admittedly, is not very much), black holes are suspiciously simple objects. Regardless of what falls in... black holes can be described by three and only three simple numbers: charge, mass and spin. The reason this is suspicious is that something had to happen to all that juicy information that fell into those two black holes. The simplest solution is the theorem, first coined by the American physicist John Wheeler, that "black holes have no hair" — they...