SpaceJibe

April 25, 2016

Air Force maglev sled breaks record at 633 mph

Filed under: Cool, Government Policies, Military — bferrari @ 8:49 am

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In the New Mexico desert last month, a rocket-powered magnetically-levitated sled broke a world record after it blasted down a track at 633 miles per hour, faster than the cruising speed of a 747.

The test occurred at Holloman Air Force Base on a special 2100-foot track on March 4. Air Force video shows the one-ton vehicle rocketing down the track, a fiery, dusty plume behind it.

“We have a magnetically-levitated sled, where we use a very cold liquid helium to essentially levitate the sled via superconducting magnetics,” Lt. Col. Shawn Morgenstern, the commander of the 846th Test Squadron, said in the video.

“The test today was significantly faster than any test that we’ve previously done,” Morgenstern added.

The Air Force said that the sled accelerated at a rate of 928 feet per second. Before this test, the sled had reached 513 mph.

Magnetic levitation systems allow for vehicles to travel in a very low-friction environment, permitting incredibly fast speeds— last year, a Japanese maglev train traveled at 374 mph. And Elon Musk, the CEO of Tesla Motors and SpaceX, has proposed a system called the Hyperloop that would use a related technology to move people or cargo at breathtaking speeds.

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April 21, 2016

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems

Filed under: Cool, Gadgets — bferrari @ 1:54 pm

DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.

Your math teacher lied to you. Sometimes getting your sums wrong is a good thing.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems
DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.
by Tom Simonite April 14, 2016
So says Joseph Bates, cofounder and CEO of Singular Computing, a company whose computer chips are hardwired to be incapable of performing mathematical calculations correctly. Ask it to add 1 and 1 and you will get answers like 2.01 or 1.98.

The Pentagon research agency DARPA funded the creation of Singular’s chip because that fuzziness can be an asset when it comes to some of the hardest problems for computers, such as making sense of video or other messy real-world data. “Just because the hardware is sucky doesn’t mean the software’s result has to be,” says Bates.

A chip that can’t guarantee that every calculation is perfect can still get good results on many problems but needs fewer circuits and burns less energy, he says.

Bates has worked with Sandia National Lab, Carnegie Mellon University, the Office of Naval Research, and MIT on tests that used simulations to show how the S1 chip’s inexact operations might make certain tricky computing tasks more efficient. Problems with data that comes with built-in noise from the real world, or where some approximation is needed, are the best fits. Bates reports promising results for applications such as high-resolution radar imaging, extracting 3-D information from stereo photos, and deep learning, a technique that has delivered a recent burst of progress in artificial intelligence.

In a simulated test using software that tracks objects such as cars in video, Singular’s approach was capable of processing frames almost 100 times faster than a conventional processor restricted to doing correct math—while using less than 2 percent as much power.

Bates is not the first to pursue the idea of using hand-wavy hardware to crunch data more efficiently, a notion known as approximate computing (see “10 Breakthrough Technologies 2008: Probabilistic Chips”). But DARPA’s investment in his chip could give the fuzzy math dream its biggest tryout yet.

Bates is building a batch of error-prone computers that each combine 16 of his chips with a single conventional processor. DARPA will get five such machines sometime this summer and plans to put them online for government and academic researchers to play with. The hope is that they can prove the technology’s potential and lure interest from the chip industry.

DARPA funded Singular’s chip as part of a program called Upside, which is aimed at inventing new, more efficient ways to process video footage. Military drones can collect vast quantities of video, but it can’t always be downloaded during flight, and the computer power needed to process it in the air would be too bulky.

It will take notable feats of software and even cultural engineering for imprecise hardware to take off. It’s not easy for programmers used to the idea that chips are always super-precise to adapt to ones that aren’t, says Christian Enz, a professor at the Swiss Federal Institute of Technology in Lausanne who has built his own approximate computing chips. New tools will be needed to help them do that, he says.

But Deb Roy, a professor at the MIT Media Lab and Twitter’s chief media scientist, says that recent trends in computing suggest approximate computing may find a readier audience than ever. “There’s a natural resonance if you are processing any kind of data that is noisy by nature,” he says. That’s become more and more common as programmers look to extract information from photos and video or have machines make sense of the world and human behavior, he adds.

 

The Curious Link Between the Fly-By Anomaly and the “Impossible” EmDrive Thruster

The same theory that explains the puzzling fly-by anomalies could also explain how the controversial EmDrive produces thrust.

About 10 years ago, a little-known aerospace engineer called Roger Shawyer made an extraordinary claim. Take a truncated cone, he said, bounce microwaves back and forth inside it and the result will be a thrust toward the narrow end of the cone. Voila … a revolutionary thruster capable of sending spacecraft to the planets and beyond. Shawyer called it the EmDrive.

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Shawyer’s announcement was hugely controversial. The system converts one type of energy into kinetic energy, and there are plenty of other systems that do something similar. In that respect it is unremarkable.

The conceptual problems arise with momentum. The system’s total momentum increases as it begins to move. But where does this momentum come from? Shawyer had no convincing explanation, and critics said this was an obvious violation of the law of conservation of momentum.

Shawyer countered with experimental results showing the device worked as he claimed. But his critics were unimpressed. The EmDrive, they said, was equivalent to generating a thrust by standing inside a box and pushing on the sides. In other words, it was snake oil.

Since then, something interesting has happened. Various teams around the world have begun to build their own versions of the EmDrive and put them through their paces. And to everyone’s surprise, they’ve begun to reproduce Shawyer’s results. The EmDrive, it seems, really does produce thrust.
In 2012, a Chinese team said it had measured a thrust produced by its own version of the EmDrive. In 2014, an American scientist built an EmDrive and persuaded NASA to test it with positive results.

And last year, NASA conducted its own tests in a vacuum to rule out movement of air as the origin of the force. NASA, too, confirmed that the EmDrive produces a thrust. In total, six independent experiments have backed Shawyer’s original claims.

That leaves an important puzzle—how to explain the seeming violation of conservation of momentum.

Today we get an answer of sorts thanks to the work of Mike McCulloch at Plymouth University in the U.K. McCulloch’s explanation is based on a new theory of inertia that makes startling predictions about the way objects move under very small accelerations.

First some background. Inertia is the resistance of all massive objects to changes in motion or accelerations. In modern physics, inertia is treated as a fundamental property of massive objects subjected to an acceleration. Indeed, mass can be thought of as a measure of inertia. But why inertia exists at all has puzzled scientists for centuries.

McCulloch’s idea is that inertia arises from an effect predicted by general relativity called Unruh radiation. This is the notion that an accelerating object experiences black body radiation. In other words, the universe warms up when you accelerate.

According to McCulloch, inertia is simply the pressure the Unruh radiation exerts on an accelerating body.

That’s hard to test at the accelerations we normally observe on Earth. But things get interesting when the accelerations involved are smaller and the wavelength of Unruh radiation gets larger.

At very small accelerations, the wavelengths become so large they can no longer fit in the observable universe. When this happens, inertia can take only certain whole-wavelength values and so jumps from one value to the next. In other words, inertia must quantized at small accelerations.

McCulloch says there is observational evidence for this in the form of the famous fly by anomalies. These are the strange jumps in momentum observed in some spacecraft as they fly past Earth toward other planets. That’s exactly what his theory predicts.

Testing this effect more carefully on Earth is hard because the accelerations involved are so small. But one way to make it easier would be to reduce the size of allowed wavelengths of Unruh radiation. “This is what the EmDrive may be doing,” says McCulloch.

The idea is that if photons have an inertial mass, they must experience inertia when they reflect. But the Unruh radiation in this case is tiny. So small in fact that it can interact with its immediate environment. In the case of the EmDrive, this is the truncated cone.

The cone allows Unruh radiation of a certain size at the large end but only a smaller wavelength at the other end. So the inertia of photons inside the cavity must change as they bounce back and forth. And to conserve momentum, this must generate a thrust.

McCulloch puts this theory to the test by using it to predict the forces it must generate. The precise calculations are complex because of the three-dimensional nature of the problem, but his approximate results match the order of magnitude of thrust in all the experiments done so far.

Crucially, McCulloch’s theory makes two testable predictions. The first is that placing a dielectric inside the cavity should enhance the effectiveness of the thruster.

The second is that changing the dimensions of the cavity can reverse the direction of the thrust. That would happen when the Unruh radiation better matches the size of the narrow end than the large end. Changing the frequency of the photons inside the cavity could achieve a similar effect.

McCulloch says there is some evidence that exactly this happens. “This thrust reversal may have been seen in recent NASA experiments,” he says.

That’s an interesting idea. Shawyer’s EmDrive has the potential to revolutionize spaceflight because it requires no propellant, the biggest limiting factor in today’s propulsion systems. But in the absence of any convincing explanation for how it works, scientists and engineers are understandably wary.

McCulloch’s theory could help to change that, although it is hardly a mainstream idea. It makes two challenging assumptions. The first is that photons have inertial mass. The second is that the speed of light must change within the cavity. That won’t be easy for many theorists to stomach.

But as more experimental confirmations of Shawyer’s EmDrive emerge, theorists are being forced into a difficult position. If not McCulloch’s explanation, then what?

Ref: arxiv.org/abs/1604.03449 : Testing Quantized Inertia on the EmDrive

April 19, 2016

Large Hadron Collider results may hint at a new era of physics

Filed under: Big Bang, Black Holes, Cool, Wierd — bferrari @ 2:00 pm
The LHC (Large Hadron Collider) tunnel. (REUTERS/Denis Balibouse)

The LHC (Large Hadron Collider) tunnel. (REUTERS/Denis Balibouse)

Are we about to enter a new era of physics?  Data collected by the Large Hadron Collider in Switzerland may have identified particle activity that doesn’t fit the standard laws of physics.

The analysis by scientists including physicists at the Institute of Nuclear Physics at the Polish Academy of Sciences (IFJ PAN) could have huge scientific implications.

“There are some indications that physicists working at the LHC accelerator at the European Organization for Nuclear Research (CERN) near Geneva may see the first traces of physics beyond the current theory which describes the structure of matter,” said the IFJ PAN, in a recent press release.

The structure of matter is described by a theoretical framework called The Standard Model, which identifies the roles played by different particles. Boson particles, for example, are carriers of forces, whereas photons are related to electromagnetic interactions. Matter is formed by particles called fermions.

However, scientists, analyzing data collected by the LHCb experiment in 2011 and 2012, noticed an anomaly in the decay of a particle called a B Meson. According to the research, the traditional method for determining the particle’s decay may lead to false results.

Related: Science breakthrough? Physicists may have discovered Higgs boson relative

Could the anomaly hint at a new understanding of the Universe? Scientists are certainly intrigued by the anomaly. To put it in terms of the cinema, where we once only had a few leaked scenes from an much-anticipated blockbuster, the LHC has finally treated fans to the first real trailer,” said Professor Mariusz Witek of IFJ PAN, in the release.

Witek notes that the framework used to describe the structure of matter poses plenty of questions for scientists. “The Standard Model cannot explain all the features of the Universe,” he said. “It doesn’t predict the masses of particles or tell us why fermions are organized in three families. How did the dominance of matter over antimatter in the universe come about? What is dark matter? Those questions remain unanswered.”

To further illustrate his point, the Professor notes that gravity isn’t even included in the Standard Model.

However, scientists caution that more research is needed on the B Meson anomaly. “We can’t call it a discovery. Not yet,” said the IFJ PAN.

CERN spokesman Arnaud Marsollier told FoxNews.com that the B Meson data, which first emerged last year, are not conclusive. “More data are needed before we can tell anything significant on this, so we will have to wait for the LHC to restart (soon),” he explained via email, noting the importance of patience when recording and analyzing data. “Science needs time!” he added.

Related: Revamped Large Hadron Collider set to restart

CERN is currently starting powering tests on the huge particle accelerator. “Beams should be back by the end of the month or early April, and collisions sometimes next month if everything goes as planned,” said Marsollier.

Oxford University Physics Professor Guy Wilkinson, who serves as the spokesman for the LHCb experiment, told FoxNews.com that CERN’s B Meson data is “extremely interesting,” but noted that it could be a couple of years before scientists perform a full analysis. “When we analyse this new sample in a year or two we will be able to make a fresh and, I hope, more categorical statement on this topic,” he explained, via email.

The 17-mile LHC was built between 1998 and 2008 to help scientists test some theories of particle and high-energy physics and advance understanding of physical laws.

In 2012 the Collider won global acclaim with the discovery of the long-sought Higgs boson  particle, which explains the behavior of other particles. Physicists Peter Higgs and Francois Englert were subsequently awarded the 2013 Nobel Prize in Physics.

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April 12, 2016

A Visionary Project Aims for Alpha Centauri, a Star 4.37 Light-Years Away

Filed under: Uncategorized — bferrari @ 1:49 pm

Can you fly an iPhone to the stars?

In an attempt to leapfrog the planets and vault into the interstellar age, a bevy of scientists and other luminaries from Silicon Valley and beyond, led by Yuri Milner, the Russian philanthropist and Internet entrepreneur, announced a plan on Tuesday to send a fleet of robots no bigger than iPhones to Alpha Centauri, the nearest star system, 4.37 light-years away.

If it all worked out — a cosmically big “if” that would occur decades and perhaps $10 billion from now — a rocket would deliver a “mother ship” carrying a thousand or so small probes to space. Once in orbit, the probes would unfold thin sails and then, propelled by powerful laser beams fromEarth, set off one by one like a flock of migrating butterflies across the universe.

Within two minutes, the probes would be more than 600,000 miles from home — as far as the lasers can maintain a tight beam — and moving at a fifth of the speed of light. But it would still take 20 years for them to get to Alpha Centauri. Those that survived would zip past the stars, making measurements and beaming pictures back to Earth.

Much of this plan is probably half a lifetime away. Mr. Milner and his colleagues estimate that it could take 20 years to get the mission off the ground and into the heavens, 20 years to get to Alpha Centauri and another four years for the word from outer space to come home. And there is still the matter of attracting billions of dollars to pay for it.

Alpha Centauri, the closest star system to Earth’s solar system. An effort led by the billionaire Yuri Milner aims to send a fleet of small probes there. (European Southern Observatory)

Alpha Centauri, the closest star system to Earth’s solar system. An effort led by the billionaire Yuri Milner aims to send a fleet of small probes there. (European Southern Observatory)

“I think you and I will be happy to see the launch,” Mr. Milner, 54, said in an interview, adding that progress in medicine and longevity would determine whether he would live to see the results.

“We came to the conclusion it can be done: interstellar travel,” Mr. Milner said. He announced the project, called Breakthrough Starshot, in a news conference in New York on Tuesday, 55 years after Yuri Gagarin — for whom Mr. Milner is named — became the first human in space.

In a statement released by Breakthrough Starshot, the English cosmologist and author Stephen Hawking said: “Earth is a beautiful place, but it might not last forever. Sooner or later we must look to the stars.”

Dr. Hawking is one of three members of the board of directors for the mission, along with Mr. Milner and Mark Zuckerberg, the Facebook founder.

The project will be directed by Pete Worden, a former director of NASA’s Ames Research Center and the chairman of the Breakthrough Prize Foundation, which Mr. Milner founded and of which the new venture is an offshoot. He has a prominent cast of advisers, including the Harvard astronomer Avi Loeb as chairman; the British astronomer royal Martin Rees; the Nobel Prize-winning astronomer Saul Perlmutter, of the University of California, Berkeley; Ann Druyan, producer of the TV show “Cosmos” and widow of Carl Sagan; and the mathematician and author Freeman Dyson, of the Institute for Advanced Study in Princeton, N.J.

“There are about 20 key challenges we are asking the world’s scientific experts to help us with — and we are willing to financially support their work,” Dr. Worden said in an email.

A detailed technical description of the project will appear on the project’s website.

Estimating that the project could cost $5 billion to $10 billion, Mr. Milner is initially investing $100 million for research and development. He said he was hoping to lure other investors, especially from international sources.

Most of that money would go toward a giant laser array, which could be used to repeatedly send probes toward any star (as long as the senders were not looking for return mail anytime soon) or around the solar system, perhaps to fly through the ice plumes of Saturn’s moon Enceladus, which might contain microbes — tiny forms of life.

In a sense, the start of this space project reflects the make-it-break-it mode of Silicon Valley. Rather than send one big, expensive spacecraft on a journey of years, send thousands of cheap ones. If some break or collide with space junk, others can take their place.

Interstellar travel is a daunting and humbling notion. Alpha Centauri is an alluring target for such a trip: It is the closest star system to our own, and there might be planets in the system. The system consists of three stars: Alpha Centauri A and Alpha Centauri B, sunlike stars that circle each other, and Proxima Centauri, which may be circling the other two. In recent years, astronomers have amassed data suggesting the possibility of an Earth-size planet orbiting Alpha Centauri B.

It would take Voyager 1, humanity’s most distant space probe, more than 70,000 years to reach Alpha Centauri if it were headed in that direction, which it is not.

Over the years, a variety of propulsion schemes have been hatched to cross the void more quickly. In 1962, shortly after lasers had been invented, Robert Forward, a physicist and science fiction author, suggested that they could be used to push sails in space.

In 2011, Darpa, the Defense Advanced Research Projects Agency, got into the act with 100 Year Starship, a contest to develop a business plan for interstellar travel.

By all accounts, Mr. Milner was initially skeptical of an interstellar probe.

But three trends seemingly unrelated to space travel — advances in nanotechnology and lasers and the relentless march of Moore’s Law, making circuits ever smaller and more powerful — have converged in a surprising way.

It is now possible to fit the entire probe with computers, cameras and electrical power, a package with a mass of only one gram, a thirtieth of an ounce.

That, Dr. Loeb said, is about what the guts of an iPhone, stripped of its packaging and displays, amount to.

April 11, 2016

NASA races to save planet-hunting Kepler spacecraft

Filed under: Uncategorized — bferrari @ 10:29 am

Image:  NASA's Kepler spacecraftNASA is trying to resuscitate its planet-hunting Kepler spacecraft, in a state of emergency nearly 75 million miles away.

The treasured spacecraft — responsible for detecting nearly 5,000 planets outside our solar system — slipped into emergency mode sometime last week. The last regular contact was April 4; everything seemed normal then.

Ground controllers discovered the problem Thursday, right before they were going to point Kepler toward the center of the Milky Way as part of a new kind of planetary survey. Kepler was going to join ground observatories in surveying millions of stars in the heart of our galaxy, in hopes of finding planets far from their suns, like our own outer planets, as well as stray planets that might be wandering between stars.

This is the latest crisis in the life of Kepler.

Launched in 2009, the spacecraft completed its primary mission in 2012. Despite repeated breakdowns, Kepler kept going on an extended mission dubbed K2 — until now. The vast 75 million-mile distance between Kepler and Earth make it all the harder to fix.

“Even at the speed of light, it takes 13 minutes for a signal to travel to the spacecraft and back,” mission manager Charlie Sobeck said in a weekend web update from NASA’s Ames Research Center in Mountain View, Calif.

Recovering from this emergency condition “is the team’s priority at this time,” Sobeck said.

More than 1,000 of Kepler’s detected 5,000 exoplanets have been confirmed to date, according to NASA.

Kepler is named after the 17th century German astronomer and mathematician Johannes Kepler.

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