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New research suggests magnetars are produced by the deaths of massive stars that were formed by stellar mergers. Photo ESO/L. Calçada Oct. 10 (UPI) -- With the help of computer simulations, scientists have come up with an explanation for the formation of the strongest magnets in the universe, magnetars. Models suggest stellar mergers can produce strong magnetic fields. When the magnetic star produced by a merger dies, a magnetar can form. Magnetars are neutron stars -- collapsed stellar cores -- with extremely powerful magnetic fields. The sun features an outer layer of convective activity that produces strong magnetic fields, but...

I just won a bet I made in 2002 with physicist Michio Kaku. I bet him $1,000 that “by 2020, no one will have won a Nobel Prize for work on superstring theory, membrane theory, or some other unified theory describing all the forces of nature.” This year’s Nobel Prize in Physics, which recognized solid work in cosmology (yay Jim Peebles!) and astronomy, was Kaku’s last chance to win before 2020. Kaku and I made the bet under the auspices of Long Bets, a “public arena for enjoyably competitive predictions, of interest to society, with philanthropic money at stake.” Long...

In the cold wilderness of space, galaxies huddle together around the campfires of stars and the assuring pull of supermassive black holes. Between these cozy clusters of galaxies, where empty space stretches on for millions of light-years all around, a faint highway of gas bridges the darkness. This gassy, intergalactic network is known in cosmological models as the cosmic web. Made of long filaments of hydrogen left over from the Big Bang, the web is thought to contain most (more than 60%) of the gas in the universe and to directly feed all of the star-producing regions in space. At...

Albert Einstein received the Nobel Prize for explaining the photoelectric effect: in its most intuitive form, a single atom is irradiated with light. According to Einstein, light consists of particles (photons) that transfer only quantized energy to the electron of the atom. If the photon’s energy is sufficient, it knocks the electrons out of the atom. But what happens to the photon’s momentum in this process? Physicists at Goethe University are now able to answer this question. To do so, they developed and constructed and new spectrometer with previously unattainable resolution. Doctoral student Alexander Hartung became a father twice during...

But now a pair of scientists suggests that some black holes may not be black holes at all. Instead, they may be weird objects chock-full of dark energy — the mysterious force thought to be pushing at the bounds of the universe, causing it to expand at an ever-increasing rate. Croker and Joel Weiner, a professor emeritus in mathematics at the same university, were looking at Friedmann's equations, which are simplified from Einstein's theory of general relativity.... Physicists use Friedmann's equations to describe the expansion of the universe, in part because the math is simpler than in Einstein's body of...

Primordial black holes (PBHs) are old and relatively small black holes that emerged soon after the Big Bang. They are thought to have been formed as a result of density fluctuations in the very early universe. It is believed that PBHs with the lowest mass have likely evaporated. However, those with larger masses may still exist, evaporating at the present epoch—even though they have been never directly observed. Astronomers Jakub Scholtz of Durham University and James Unwin of University of Illinois at Chicago, assume that PBHs could reside even closer to us than we think. In a recently published paper,...

Warp drive is one of the many futuristic ideas proposed in Star Trek, allowing for faster-than-light travel across the galaxy. Einstein's Theory of Relativity prevents anything from moving faster than light. In 1994, a theoretical physicist proposed a workaround: creating a bubble within space-time that would twist distances, allowing anything within the bubble to travel long distances. Many think it makes theoretical sense, but is practically unworkable. An undergrad at the University of Alabama wants to restart the conversation, and he's focused on how much energy such a bubble would need. Star Trek's science fiction has been intermingled with...

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...