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By 2013, the European Planck space telescope's detailed measurements of cosmic radiation seemed to have yielded the final answer: 13.8 billion years old. All that was left to do was to verify that number using independent observations of bright stars in other galaxies. Then came an unexpected turn of events. A few teams, including one led by Nobel laureate Adam Riess of the Space Telescope Science Institute in Baltimore, set out to make those observations. Instead of confirming Planck's measurements, they started getting a distinctly different result. At first, the common assumption was that Riess and the other galaxy-watchers had...

A Neutrino Beam Beaconby Paul Gilsteron May 17, 2019 If you want to look for possible artifacts of advanced civilizations, as do those practicing what is now being called Dysonian SETI, then it pays to listen to the father of the field. My friend Al Jackson has done so and offers a Dyson quote to lead off his new paper: “So the first rule of my game is: think of the biggest possible artificial activities with limits set only by the laws of physics and look for those.” Dyson wrote that in a 1966 paper that repays study today (citation...

For the first time, researchers have performed a version of the famous double-slit experiment with antimatter particles.The double-slit experiment demonstrates one of the fundamental tenets of quantum physics: that pointlike particles are also waves. In the standard version of the experiment, particles travel through a pair of slits in a solid barrier. On a screen on the other side, an interference pattern typical of waves appears. Crests and troughs emerging from each slit reinforce each other or cancel each other out as they overlap, creating alternating bands of high and low particle density on the screen.This kind of experiment has...

For something so commonplace, glass is actually an incredible mystery; an enigma of physics that has defied understanding since humans first encountered it millennia ago. The reason is this: glass is no ordinary solid. But nor is it a liquid. It lies somewhere in between, a strange hybrid known as an amorphous solid – something that's firm to the touch, yet down at the atomic level, it actually behaves rather more like liquid.

Acceleration as a function of radius in NGC 4455, one of the studied galaxies As fascinating as it is mysterious, dark matter is one of the greatest enigmas of astrophysics and cosmologyIt is thought to account for 90 percent of the matter in the universe, but its existence has been demonstrated only indirectly, and has recently been called into question New research conducted by SISSA removes the recent doubts on the presence of dark matter within galaxies, disproving the empirical relations in support of alternative theories. The study, published in the Astrophysical Journal, also offers new insights into understanding the...

A FORMER NASA scientist has claimed time travel is possible because the “speed of light is changing”. ============================================================== Louise Riofrio is involved in a project that will put an atomic clock into the International Space Station to “verify” her theory. She reached the conclusion that the speed of light is changing while working at NASA. The scientist analysed lasers that bounced off reflectors left by astronauts on the moon, which appeared to show the moon was moving too fast. But – when she compared it to various experiments on Earth using fossils, observations of ancient eclipses and computer simulations –...

Explaining a discrepancy between what was happening 13 billion years ago and now may require new physics. It's become clear that something in the cosmos just doesn't add up. The universe is getting bigger every second. In fact, it's expanding at a much faster rate than it should. For some time now there's been a mismatch in observations of the early universe done with the European Space Agency's Planck Telescope and what astronomers see when they measure the more nearby, modern parts of space with NASA's Hubble Telescope. (Keep in mind that looking at distant parts of the universe with...

One of Stephen Hawking's most famous theories about dark matter — that this mysterious and invisible substance is made up of primordial black holes — recently suffered a huge blow. That conclusion comes from a massive telescope that captured an image of an entire galaxy in one shot. The findings don't completely rule out Stephen Hawking's famous notion. But they suggest that primordial black holes would have to be truly tiny to explain dark matter. Dark matter mystery Dark matter is the name given by physicists to explain a particularly mysterious phenomenon: Everything in the universe moves, orbits and rotates...

The laws of physics are such that one photon just passes by another with zero interaction. But in a new experiment inside the world's most powerful atom smasher, researchers got a glimpse of the impossible: photons bumping into each other. The answer lies in one of the most inscrutable and yet delicious aspects of modern physics, and it goes by the funky name of quantum electrodynamics. In this picture of the subatomic world, the photon isn't necessarily a photon. Well, at least, it's not always a photon. Particles like electrons and photons and all the other -ons continually flip back...

It takes 1 trillion times the age of the universe for a xenon-124 sample to shrink by half For the first time, researchers have directly observed an exotic type of radioactive decay called two-neutrino double electron capture.The decay, seen in xenon-124 atoms, happens so sparingly that it would take 18 sextillion years (18 followed by 21 zeros) for a sample of xenon-124 to shrink by half, making the decay extremely difficult to detect. The long-anticipated observation of two-neutrino double electron capture, reported in the April 25 Nature, lays the groundwork for researchers to glimpse a yet unseen, even rarer version...

The black hole is enormous, with a radius of roughly 9 billion miles... The concept of a black hole goes back to the 18th century, when the English astronomer-clergyman John Michell calculated that a sufficiently large star couldn't shine because light wouldn’t move fast enough to “lift off” and escape the star’s gravity. But Michell’s conjecture outran the physics of its time, which didn’t understand light, gravity or stars well enough to support it. The foundations for the modern understanding of black holes weren’t laid until the early 20th century, building on James Clerk Maxwell’s theory of electromagnetism and Albert...

One of the reasons why humans are handicapped in our understanding of reality is because of our reliance on the “scientific method”. It is a system based on observation. The problem with this method is that our understanding of reality is corrupted by the limits imposed by observation. Indeed, as well well know, it is the perception of the observer that changes our reality. This is a well understood rule. If you the reader, don’t “get it”, then you need to study quantum mechanics 101. For in the last two decades the entire foundation of our understanding of reality has...

Scientists improved the performance of electricity-harvesting crystals by adding the rare earth metal samarium. Photo by Wikimedia Commons ============================================================ April 19 (UPI) -- Researchers have discovered that the addition of a rare earth metal significantly improves the performance of piezoelectric crystals. Piezoelectric crystals are used in sensors, including underwater sonars and medical ultrasound imaging devices. These technologies use perovskite oxide crystals, or PMN-PT crystals. Scientists have also tried to use piezoelectric crystals, which convert mechanical oscillations into electricity, to power wearable electronics and other types of novel technologies. An international team of scientists from Australia, China and the United States...

Scientists believe that time is continuous, not discrete—roughly speaking, they believe that it does not progress in "chunks," but rather "flows," smoothly and continuously. So they often model the dynamics of physical systems as continuous-time "Markov processes," named after mathematician Andrey Markov. Indeed, scientists have used these processes to investigate a range of real-world processes from folding proteins, to evolving ecosystems, to shifting financial markets, with astonishing success. In a pair of papers, one appearing in this week's Nature Communications and one appearing recently in the New Journal of Physics, physicists at the Santa Fe Institute and MIT have shown...

Astronomers have captured the first image of a black hole, heralding a revolution in our understanding of the universe’s most enigmatic objects. The picture shows a halo of dust and gas, tracing the outline of a colossal black hole, at the heart of the Messier 87 galaxy, 55m light years from Earth.

The first image of a black hole has been captured by astronomers, heralding a revolution in our understanding of the universe’s most enigmatic objects. The picture shows a halo of dust and gas, tracing the outline of a colossal black hole, at the heart of the Messier 87 galaxy, 55 million light years from Earth. The black hole itself – a cosmic trapdoor from which neither light nor matter can escape – is unseeable. But the latest observations take astronomers right to its threshold for the first time, illuminating the event horizon beyond which all known physical laws break down.

https://www.cnn.com/2019/04/10/us/katie-bouman-mit-black-hole-algorithm-sci-trnd/index.html

Nearly 40 years after it was proposed, mathematicians have settled one of the most profound questions in the study of general relativity. In a paper posted online last fall, mathematicians Mihalis Dafermos and Jonathan Luk have proven that the strong cosmic censorship conjecture, which concerns the strange inner workings of black holes, is false.“I personally view this work as a tremendous achievement — a qualitative jump in our understanding of general relativity,” emailed Igor Rodnianski, a mathematician at Princeton University.The strong cosmic censorship conjecture was proposed in 1979 by the influential physicist Roger Penrose. It was meant as a...

The heart of every major galaxy is said to contain a supermassive black hole — a place where anything, including light, can be devoured to the point of no return. For years, scientists have struggled to capture one of these deadly masses on camera, since the absence of light renders them nearly impossible to see. Now, for the first time, a group of scientists from the international Event Horizon Telescope (EHT) project are expected to unveil a photograph of a black hole to the public.

There are ghostly shapes hidden in magnetic fields. They're not made of stuff in the way a lightning bolt or a beam of light is. A lighting bolt carries a fairly defined group of electrons from the sky all the way to the ground.... But magnetic fields contain things called skyrmions that are different from electrons and photons; a skyrmion is a knot of magnetic field lines looping around each other. As it drifts from one spot to the next, a skyrmion makes itself anew out of the magnetic field lines that are already there. The knot holds together because...