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Ron Cowen 3-22-2016 In tunnels deep inside a granite mountain at Daya Bay, a nuclear reactor facility some 55 kilometers from Hong Kong, sensitive detectors are hinting at the existence of a new form of neutrino, one of nature’s most ghostly and abundant elementary particles.Neutrinos, electrically neutral particles that sense only gravity and the weak nuclear force, interact so feebly with matter that 100 trillion zip unimpeded through your body every second. They come in three known types: electron, muon and tau. The Daya Bay results suggest the possibility that a fourth, even more ghostly type of neutrino exists —...

In the fall of 2019, Betelgeuse began dimming significantly, losing about two-thirds of its brightness by February. This dramatic dip spurred speculation that the star's demise may have been imminent — perhaps just weeks away. But the dramatic sky show didn't happen: Betelgeuse powered through the dimming episode and returned to its normal brightness by May of this year. The recovery sparked a new round of speculation, this time about the dimming's cause. Some scientists attributed the doldrums to a light-blocking dust cloud, for example, whereas others said big starspots on Betelgeuse's surface were likely to blame. A new study...

Most FRBs originate hundreds of millions of light-years away. This one came from inside the Milky Way. Thirty thousand years ago, a dead star on the other side of the Milky Way belched out a powerful mixture of radio and X-ray energy. On April 28, 2020, that belch swept over Earth, triggering alarms at observatories around the world. The signal was there and gone in half a second, but that's all scientists needed to confirm they had detected something remarkable: the first ever "fast radio burst" (FRB) to emanate from a known star within the Milky Way, according to a...

Metrology is the science of estimations and measurements. We are used to dealing with probabilities that range from 0% (never happens) to 100% (always happens). To explain results from the quantum world however, the concept of probability needs to be expanded to include a so-called quasi-probability, which can be negative. This quasi-probability allows quantum concepts such as Einstein's 'spooky action at a distance' and wave-particle duality to be explained in an intuitive mathematical language. An experiment whose explanation requires negative probabilities is said to possess 'quantum negativity.' In state-of-the-art metrology however, the probes are quantum particles, which can be controlled...

Last year, scientists detected the most energetic gamma ray burst we've ever seen. A distant galaxy spat out a colossal flare in the range of a trillion electron volts (TeV), providing invaluable new insight into the physics of these incredibly energetic events. That was pretty amazing on its own - but now astrophysicists have used the burst to perform a new, precise test of the theory of general relativity. And - quelle surprise! - this test found that the speed of light is constant in a vacuum. Relativity, once again, has passed with flying colours. The test hinges on a...

Artist's conception. Image: Caltech/R. Hurt (IPAC) Astronomers from Caltech have reported that they’ve observed a collision between two black holes. Normally such an event is invisible, but this time a more massive black hole sitting nearby helped illuminate the other two as they collided. If confirmed, the findings, published in Physical Review Letters, would be the first optical observations ever made of a black hole merger. What happened: First detected in May 2019 and dubbed S190521g, the merger happened about 4 billion light-years away, within the vicinity of a supermassive black hole called J1249+3449. This object is 100 million times...

A small team of researchers at Purdue University has found the strongest evidence yet of the existence of abelian anyons. They have written a paper describing experiments they conducted designed to reveal the existence of the quasiparticles and have uploaded it to the arXiv preprint server while they await peer review. Anyons are neither bosons nor fermions—in fact, they are not elementary particles at all. Instead, they are classified as quasiparticles that exist in two dimensions. They can be observed, theoretically speaking, when they appear as disturbances in two-dimensional sheets of materials. Theoretical physicists have suggested their existence since the...

All tetraquarks and pentaquarks that have been discovered so far contain two charm quarks, which are relatively heavy, and two or three light quarks – up, down or strange. This particular configuration is indeed the easiest to discover in experiments. But the latest tetraquark discovered by LHCb, which has been dubbed X(6900), is composed of four charm quarks. Produced in high-energy proton collisions at the Large Hadron Collider, the new tetraquark was observed via its decay into pairs of well-known particles called J/psi mesons, each made of a charm quark and a charm antiquark. This makes it particularly interesting as...

There's something unusual lurking out in the depths of space: Astronomers have discovered four faint objects that at radio wavelengths are highly circular and brighter along their edges. And they're unlike any class of astronomical object ever seen before. The objects, which look like distant ring-shaped islands, have been dubbed odd radio circles, or ORCs, for their shape and overall peculiarity. Astronomers don't yet know exactly how far away these ORCs are, but they could be linked to distant galaxies. All objects were found away from the Milky Way's galactic plane and are around 1 arcminute across (for comparison, the...

Could the Big Bang have created a hidden 'twin' Universe?

Big bounces may make the Universe able to support stars and life. A bouncing universe that expands and then shrinks every trillion years or so could explain one of the most puzzling problems in cosmology: how we can exist at all. If this explanation, proposed in Science1 by Paul Steinhardt at Princeton University, New Jersey, and Neil Turok at the University of Cambridge, UK, seems slightly preposterous, that can't really be held against it. Astronomical observations over the past decade have shown that "we live in a preposterous universe", says cosmologist Sean Carroll of the University of Chicago. "It's our...

Images from the Hubble Space Telescope have revealed a so-called "ring of dark matter" circling a galaxy cluster. Does dark matter exist? Or is electricity a better explanation for the structure of the universe? {Galaxy Cluster CL0024+17 with an overlay showing a supposed dark matter ring. Credit: NASA, ESA, M. J. Jee and H. Ford et al. (Johns Hopkins University)} In a recent announcement, NASA and the European Space Agency (ESA) reported the discovery of something in deep space that seems to confirm previously inferred observations of "dark matter." Although "dark matter" cannot be seen or detected by instruments, its...

Astronomers have been grappling with the mystery of dark matter for a long time, and I mean a looong time. The history of dark-matter investigations goes back at least to 1906, when physicist Henri Poincaré’s 1906 speculated about the amount of “matière obscure” in the Milky Way. Or really, it goes to back to 1846 and the first successful detection of dark matter: the discovery of the planet Neptune, whose existence had been inferred by its gravitational pull well before it was actually observed. Since then, scientists have identified many different dark components in space: collapsed stars, interstellar dust, hot...

(CNN)The fastest-growing black hole in the universe is 34 billion times the mass of our sun and feasts on a meal the equivalent of our sun each day, according to a new study. This massive, hungry black hole was first identified and studied by researchers in May 2018. Previously, they believed it consumed the mass equivalent to our sun every two days. Now, they have a better understanding of this monster black hole and its gluttonous behavior. The study published Wednesday in the journal Monthly Notices of the Royal Astronomical Society. The black hole is known as J2157 and exists...

Leonard Susskind interview - If the deep laws of the universe had been ever so slightly different, human beings wouldn't, and couldn't, exist. All explanations of this exquisite fine-tuning, obvious and not-so-obvious, have problems or complexities.

On Aug. 14, 2019, a gravitational wave -- a massive ripple through the fabric of space-time -- washed over the Earth. The signal was one of the strongest ever seen by the gravitational wave scientists at the Laser Interferometer Gravitational-wave Observatory and Italy's Virgo observatory. After an alert was sent out moments after detection, teams of astronomers across the world turned their telescopes to the point in space that the wave emanated from. But their searches came up empty. No light, no X-rays, no infrared, no gamma rays. On Tuesday, researchers from the LIGO and Virgo collaborations detail their full...

Europe’s preeminent particle-physics organization will need global help to fund the project, which is expected to cost at least €21 billion and would be a follow-up to the lab’s famed Large Hadron Collider. The new machine would collide electrons with their antimatter partners, positrons, by the middle of the century. The design—to be built in an underground tunnel near CERN’s location in Geneva, Switzerland—will enable physicists to study the properties of the Higgs boson and, later, to host an even more powerful machine that will collide protons well into the second half of the century. The approval is not yet...

Behold the hot, energetic Universe. A German-Russian space telescope has just acquired a breakthrough map of the sky that traces the heavens in X-rays. The image records a lot of the violent action in the cosmos - instances where matter is being accelerated, heated and shredded. Feasting black holes, exploding stars, and searingly hot gas. The data comes from the eRosita instrument mounted on Spektr-RG. This orbiting telescope was launched in July last year and despatched to an observing position some 1.5 million km from Earth. Once commissioned and declared fully operational in December, it was left to slowly rotate...

Scientists working on the Xenon1T experiment have detected more activity within their detector than they would otherwise expect. There are three potential explanations for the new signal from the Xenon1T experiment. Two require new physics to explain, while one of them is consistent with a hypothesised dark matter particle called a solar axion. There are several theories to account for what that particle might be like. The most favoured one has been the WIMP, or Weakly Interacting Massive Particle. Physicists working on the Xenon series of experiments have spent more than a decade hunting for signs of these WIMPs. ......

Bose-Einstein condensates (BECs)—the existence of which was predicted by Albert Einstein and Indian mathematician Satyendra Nath Bose almost a century ago—are formed when atoms of certain elements are cooled to near absolute zero (0 Kelvin, minus 273.15 Celsius). At this point, the atoms become a single entity with quantum properties, wherein each particle also functions as a wave of matter. BECs straddle the line between the macroscopic world governed by forces such as gravity and the microscopic plane, ruled by quantum mechanics. Creating the fifth state of matter, especially within the physical confines of a space station, is no mean...