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An emerging consensus suggests the crash can explain distant gamma-ray bursts GREAT ESCAPE A bright jet of fast-moving particles fled the scene after two neutron stars collided, spewing material and potentially forming a black hole (shown in this artist’s illustration). When a pair of ultradense cores of dead stars smashed into one another, the collision shot a bright jet of charged subatomic particles through space. Astronomers thought no such jet had made it out of the wreckage of the neutron star crash, first detected in August 2017. But new observations of the crash site using a network of radio telescopes...

The speed of light in a vacuum is the ultimate cosmic speed limit. Just getting close to it causes problems: the weird distortions of Einstein’s relativity kick in, so time slows down, lengths go up, masses balloon and everything you thought was fixed changes. Only things that have no mass in the first place can reach light speed – photons of light being the classic example. Absolutely nothing can exceed this cosmic max.We have known about the special nature of light speed since an experiment by US physicists Albert Michelson and Edward Morley in the 1880s. They set two beams...

Breakthrough Starshot is one of the more exciting scientific ideas that has popped up in the past decade, with its promise to deliver hardware to the nearest star in time for many people currently alive to see it. While the idea would work on paper as an extrapolation of existing technology, there are a lot of details that need to be thoroughly checked out, because it’s possible that one of them could present a show-stopper. There’s a bit of good news there: Breakthrough Starshot is apparently funding the needed research to give its concept a thorough vetting. A recent posting...

Physics is built out of philosophically fascinating ideas. Or, at least, ideas that fascinate us as physicists. We are often moved to reverentially proclaim the beauty of various concepts and theories. Sometimes this beauty makes sense to other people (we're made of star stuff) and other times it's opaque (Frobenius manifolds in psuedo-Euclidean spaces). I have my own personal favorite idea. It arises from the philosophically fantastic (but mathematically moderate) workings of Einstein's relativity theory. The theory of special relativity holds that time and space are not separate entities, each operating on its own; rather they are intimately and inextricably...

Physicist James Franson of the University of Maryland, Baltimore County has captured the attention of the physics community by posting an article to the peer-reviewed New Journal of Physics in which he claims to have found evidence that suggests the speed of light as described by the theory of general relativity, is actually slower than has been thought. The theory of general relativity suggests that light travels at a constant speed of 299,792,458 meters per second in a vacuum. It's the c in Einstein's famous equation after all, and virtually everything measured in the cosmos is based on it—in short,...

NASA engineer and physicist Harold White announced a few years ago that he was working on a potentially groundbreaking idea that could allow space travel faster than the speed of light. Yes, like in “Star Trek.” And now, to boldly go where no designer has gone before, Mark Rademaker — who is collaborating with White — has created a CGI design concept for the “warp ship.” They’re calling it the IXS Enterprise. “We wanted to have a decent image of a theory conforming Warp ship to motivate young people to pursue a STEM career,” Rademaker said in an e-mail...

The speed of light is constant, or so textbooks say. But some scientists are exploring the possibility that this cosmic speed limit changes, a consequence of the nature of the vacuum of space. The definition of the speed of light has some broader implications for fields such as cosmology and astronomy, which assume a stable velocity for light over time. For instance, the speed of light comes up when measuring the fine structure constant (alpha), which defines the strength of the electromagnetic force. And a varying light speed would change the strengths of molecular bonds and the density of nuclear

Scientists said on Thursday they recorded particles travelling faster than light - a finding that could overturn one of Einstein's fundamental laws of the universe. Antonio Ereditato, spokesman for the international group of researchers, said that measurements taken over three years showed neutrinos pumped from CERN near Geneva to Gran Sasso in Italy had arrived 60 nanoseconds quicker than light would have done. "We have high confidence in our results. We have checked and rechecked for anything that could have distorted our measurements but we found nothing," he said. "We now want colleagues to check them independently."

Physicists have confirmed the ultimate speed limit for the packets of light called photons - making time travel even less likely than thought. The speed of light in vacuum is the Universe's ultimate speed limit, but experiments in recent years suggested that single photons might beat it. If they could, theory allows for the prospect of time travel. Now, a paper in Physical Review Letters shows that individual photons too are limited to the vacuum speed limit. That means that photons maintain the principle of causality laid out in Einstein's theory of special relativity - that is, an event's effect...

Science fiction writers may have to rethink how their starship crews survive travel near or beyond the speed of light. Even the occasional hydrogen atom floating in the interstellar void would become a lethal radiation beam that would kill human crews in mere seconds and destroy a spacecraft's electronics, New Scientist reports. Just a few stray wisps of hydrogen gas -- fewer than two hydrogen atoms per cubic centimeter on average -- would translate into 7 teraelectron volts for a starship crew traveling at 99.999998 percent of the speed of light. That's as much fun for humans as standing in...

Researchers creating the tiny engines that could drive mini-starshipsMassive particle accelerators are exploring the world of the very small, but similar technology may someday propel needle-sized spacecraft to distances on a scale so large as to be almost unimaginable — between star systems. Thanks to research on nano-sized thrusters that act like portable particle accelerators, tiny spacecraft might be accelerated to near-lightspeed and sent to explore nearby stars — perhaps within our lifetimes.

The speed of light is the speed of light, and that's that. Right? Well, maybe not. Try and figure this out. Astronomers studying radiation coming from a distant galaxy found that the high energy gamma rays arrived a few minutes after the lower-energy photons, even though they were emitted at the same time. If true, this result would overturn Einstein's theory of relativity, which says that all photons should move at the speed of light. Uh oh Einstein. The discovery was made using the new MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescope, located on a mountain top on the Canary...

A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time. According to Einstein's special theory of relativity, it would require an infinite amount of energy to propel an object at more than 186,000 miles per second. However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory. The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of...

Physicists in Switzerland have confirmed that information cannot be transmitted faster than the speed of light. Nicolas Gisin and colleagues at the University of Geneva have shown that the "group velocity" of a laser pulse in an optical fibre can travel faster than the speed of light but that the "signal velocity" - the speed at which information travels - cannot (N Brunner et al. 2004 Phys. Rev. Lett. 93 203902). Two types of velocity are used to describe the propagation of a wave in a dispersive medium: the phase velocity and the group velocity. The phase velocity is the...

Will Spacecraft ever Go Faster than the speed of Light? Compiled by VANNROX for BlueBay Source list and references included.Primary Sources include MSNBC,NASA,Analog, and other online publications. February 16 2003  Marc Millis, who manages NASA?s Breakthrough Propulsion Physics Program, says he?s more interested in ways ?to propel spacecraft farther, faster, more efficiently? than in the grand cosmological questions. ?And my ears perk up more when I hear about new experimental evidence than theories,? he says. There are a number of such theories based on experimental evidence. His top three of interest are: Photon Tunneling.Some experiments have indicated that photons...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 October 8 The X-Ray Jets of XTE J1550 Image Credit: CXC, NASA; Illustration Credit: M. Weiss (CXC) Explanation: The motion of ultra-fast jets shooting out from a candidate black hole star system have now been documented by observations from the orbiting Chandra X-ray Observatory. In 1998, X-ray source XTE J1550-564 underwent a tremendous outburst. Jets of material sent streaming into space at near light-speed impacted existing gas...