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Here’s what quantum supremacy does—and doesn’t—mean for computing And no, super-powerful computers are not about to take over by Martin Giles Sep 24, 2019 Google Google has reportedly demonstrated for the first time that a quantum computer is capable of performing a task beyond the reach of even the most powerful conventional supercomputer in any practical time frame—a milestone known in the world of computing as “quantum supremacy.”The ominous-sounding term, which was coined by theoretical physicist John Preskill in 2012, evokes an image of Darth Vader–like machines lording it over other computers. And the news has already produced some outlandish...

The KATRIN discovery stems from direct, high-precision measurements of how a rare type of electron-neutrino pair share energy. This approach is the same as neutrino mass experiments from the 1990s and early 2000s...both of which set the previous upper limit of the mass at 2 eV. The heart of the KATRIN experiment is the source that generates electron-neutrino pairs: gaseous tritium, a highly radioactive isotope of hydrogen. As the tritium nucleus undergoes radioactive decay, it emits a pair of particles: one electron and one neutrino, both sharing 18,560 eV of energy. KATRIN scientists cannot directly measure the neutrinos, but they...

The universe is looking younger every day, it seems. New calculations suggest the universe could be a couple billion years younger than scientists now estimate, and even younger than suggested by two other calculations published this year that trimmed hundreds of millions of years from the age of the cosmos. The huge swings in scientists' estimates — even this new calculation could be off by billions of years — reflect different approaches to the tricky problem of figuring the universe's real age.

One of the most radical and important ideas in the history of physics came from an unknown graduate student who wrote only one paper, got into arguments with physicists across the Atlantic as well as his own advisor, and left academia after graduating without even applying for a job as a professor. Hugh Everett’s story is one of many fascinating tales that add up to the astonishing history of quantum mechanics, the most fundamental physical theory we know of. Everett’s work happened at Princeton in the 1950s, under the mentorship of John Archibald Wheeler, who in turn had been mentored...

If Albert Einstein's theory of general relativity holds true, then a black hole, born from the cosmically quaking collisions of two massive black holes, should itself "ring" in the aftermath, producing gravitational waves much like a struck bell reverbates sound waves. Einstein predicted that the particular pitch and decay of these gravitational waves should be a direct signature of the newly formed black hole's mass and spin. Now, physicists from MIT and elsewhere have "heard" the ringing of an infant black hole for the first time, and found that the pattern of this ringing does, in fact, predict the black...

BEIJING, Sept. 9 (Xinhua) -- Chinese astronomers have detected repeated fast radio bursts (FRB) - mysterious signals believed to be from a source about 3 billion light years from Earth - with the largest and most sensitive radio telescope ever built. Scientists detected the signals with the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) and they are carefully cross-checking and processing them, according to researchers at the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC). FRBs are the brightest bursts known in the universe. They are called "fast" because these blips are very short, only several milliseconds in duration....

The original problem, set in 1954 at the University of Cambridge, looked for Solutions of the Diophantine Equation x3+y3+z3=k, with k being all the numbers from one to 100. Beyond the easily found small solutions, the problem soon became intractable as the more interesting answers—if indeed they existed—could not possibly be calculated, so vast were the numbers required. But slowly, over many years, each value of k was eventually solved for (or proved unsolvable), thanks to sophisticated techniques and modern computers—except the last two, the most difficult of all; 33 and 42. Professors Booker and Sutherland's solution for 42 would...

This article is not copying for me, but I have heard about this before. What if it's simply things flying in front of the radio telescope? What say FReepers?

A new school year is about to begin and along with it comes a new solution to a new problem. And Stanford University, the Harvard of the West, is proudly taking credit for discovering the problem: that people in science aren't diverse and inclusive enough. Horrors. But, being a renowned research university, it is proudly offering its solution, called: PUWMAS. That's its unprepossessing acronym for Physics Undergraduate Women and Gender Minorities at Stanford, what it calls "Stanford’s first undergraduate group dedicated to forming an inclusive community of underrepresented minorities in physics." -- snip -- What does that mean? Well, along...

SHANGHAI — More than a decade ago, Chinese physicist Pan Jian-Wei returned home from Europe to help oversee research into some of the most important technology of the 21st century. At a conference in Shanghai this summer, Pan and his team offered a rare peek at the work he described as a “revolution.” They spoke of the hacking-resistant communications networks they are building across China, the sensors they are designing to see through smog and around corners, and the prototype computers that may someday smash the computational power of any existing machine. All the gear is based on quantum technology...

Physicists have known since 1911 that electricity can flow without resistance in materials called superconductors. And in 1957, they figured out why: Under specific conditions, including typically very cold temperatures, electrons join together in pairs—something that's normally forbidden due to their mutual repulsion—and as pairs, they can flow freely. Electron pairs are named for Leon Cooper, the physicist who first described them. In addition to explaining classical superconductivity, physicists believe Cooper pairs bring about high-temperature superconductivity, an unconventional variant discovered in the 1980s. It was dubbed "high-temperature" because it occurs at temperatures that, although still very cold, are considerably higher...

Scientists, including from The Australian National University (ANU), say they have detected a black hole swallowing a neutron star for the first time. Neutron stars and black holes are the super-dense remains of dead stars. On Wednesday 14 August 2019, gravitational-wave discovery machines in the United States and Italy detected ripples in space and time from a cataclysmic event that happened about 8,550 million trillion kilometres away from Earth.

The supermassive black hole at the heart of the Milky Way, Sagittarius A*, is relatively quiet. It's not an active nucleus, spewing light and heat into the space around it; most of the time, the black hole's activity is low key, with minimal fluctuations in its brightness. When we view that radiation with a telescope using the infrared range, it translates as brightness. Normally, the brightness of Sgr A* flickers a bit like a candle, varying from minutes to hours. But when the surroundings of a black hole flare that brightly, it's a sign something may have gotten close enough...

A University of Illinois at Urbana-Champaign professor who argues for a “movement against objects, truths, and knowledge” will be leading a confab at Minnesota’s Carleton College this October. Carleton’s convocation series, described as “a shared campus experience that brings students, faculty, and staff together for […] a lecture or presentation from specialists in a variety of disciplines,” have “a rich history” dating back to the early 1940s The relationship between humans, mathematics, and the planet has been one steeped too long in domination and destruction […] Drawing upon Indigenous worldviews to reconceptualize what mathematics is and how it is practiced,...

Inventors of centuries past and scientists of today have found ingenious ways to make our lives better with magnets – from the magnetic needle on a compass to magnetic data storage devices and even MRI body scan machines. All of these technologies rely on magnets made from solid materials. But what if you could make a magnetic device out of liquids? Using a modified 3D printer, a team of scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have done just that. Their findings, to be published July 19 in the journal Science, could lead to a...

The fact that no one has died from being struck by dark matter is enough proof to rule out certain ideas about the mysterious stuff, according to one new theory paper. There’s a conundrum facing physicists: Most of the universe’s mass appears to be missing, based on observations of the universe’s structure, how galaxies move, and how they seem to warp distant light. Thousands of physicists are now hunting for what might be producing these effects. But the mere fact that we’re alive here on Earth can offer some insight as to what dark matter isn’t, and the researchers behind...

These galaxies are selected from a Hubble Space Telescope program to measure the expansion rate of the universe, called the Hubble constant. The value is calculated by comparing the galaxies' distances to the apparent rate of recession away from Earth (due to the relativistic effects of expanding space). By comparing the apparent brightnesses of the galaxies' red giant stars with nearby red giants, whose distances were measured with other methods, astronomers are able to determine how far away each of the host galaxies are. This is possible because red giants are reliable milepost markers because they all reach the same...

The more entanglement in the so-called Hilbert space—the realm where quantum information processing can take place—the better. Previous photonic approaches were able to reach 18 qubits encoded in six entangled photons in the Hilbert space. Purdue researchers maximized entanglement with a gate using four qudits—the equivalent of 20 qubits—encoded in only two photons. In quantum communication, less is more. "Photons are expensive in the quantum sense because they're hard to generate and control, so it's ideal to pack as much information as possible into each photon," said Poolad Imany, a postdoctoral researcher in Purdue's School of Electrical and Computer Engineering....

A recent test has confirmed the predictions of quantum trajectory theory, which describes what happens during the long-mysterious “collapse” of a quantum system.Imagine if all our scientific theories and models told us only about averages: if the best weather forecasts could only give you the average daily amount of rain expected over the next month, or if astronomers could only predict the average time between solar eclipses. In the early days of quantum mechanics, that seemed to be its inevitable limitation: It was a probabilistic theory, telling us only what we will observe on average if we collect records for...

NASA’s Hubble telescope has recently discovered a supermassive black hole that defies existing theories about the universe, a report said. The black hole, which is about 250 million times heavier [more massive] than the sun, lies at the heart of the spiral galaxy NGC 3147 and is 140 million light-years from Earth. The Hubble telescope has detected a supermassive black hole that technically shouldn't exist, according to new findings. Spotted around the black hole was a thin “accretion disk” containing debris and gas rapidly pacing around the edge, according to findings published Thursday in the journal Monthly Notices of the...