Printing the future | sci-english.blogspot.com

3D printing may be the way mass manufacture is going, but it is also bringing out the artisan in all of us. Tim Dean looks at some of the many ways we can use this new technology. 

One moment it’s an image on a screen, the next it’s an object in your hands – today’s 3D printers make Star Trek gadgets look tame. 
Futuristic as they are, they are also taking us back to a time when individuals were able to craft their own designs. While conventional manufacturing excels at churning out mountains of identical objects, 3D printing gives today’s artisans free reign.
Here are some examples. But this is just the beginning – 3D printing is limited only by our imaginations.

Bespoke bike | sci-english.blogspot.com

Bespoke bike

Every body is different. So wouldn’t it be great if your bike were tailored to yours? Matthew Andrew, owner and designer at Flying Machine in Perth, can oblige. He teamed up with the CSIRO’s Lab 22 to produce a prototype bike, above, with 3D-printed titanium parts that can be tailored to the customer’s size.
“The customer is measured up. It’s similar to buying a tailored suit. You just can’t do that with traditional manufacturing,” says Andrew.
He is already taking orders. Prices will be around $3,000 for the frame, making the bikes a premium option but by no means the most expensive on the market.

Anatomy in print |

Anatomy in print

Most people don’t appreciate being poked, prodded and dissected, so anatomy classes typically use cadavers. But they’re not easy to come by. They require expensive treatment to keep them preserved and many places restrict their use. Enter 3D printed body parts.
Paul McMenamin, director of the Centre for Human Anatomy Education at Monash University, and colleagues have scanned some of the best preserved specimens in their collection and reproduced them using a 3D printer. The results are highly detailed, accurate in terms of colour, odour free and far less expensive than plastic-impregnated “plastinated” specimens, such as those seen in the Body Worlds exhibition.
Even experienced surgeons are using these 3D-printed models, like the one pictured above, to perfect delicate operations before attempting them in the operating theatre.

Home is where you print it |

Home is where you print it

3D printing can make big objects too. In early 2014 WinSun Decoration Design Engineering Co. in China built several houses outside Shanghai using an enormous 3D printer, as seen above. This changed the building method – these houses did not rise from the ground in the conventional manner. Rather, the basic structural elements were printed using an automated gantry arm to extrude a mixture of high grade concrete and glass fibre. The parts were then assembled. The company’s aim is to build up to 10 houses a day at a cost of around $5,000 each.
A similar demonstration is slowly taking shape in Amsterdam at the 3D Print Canal House, led by DUS architects. Instead of concrete, DUS is using a custom granular plastic made from 80% vegetable oil that melts at 170°C. An oversized 3D printer called KamerMaker (or “room builder”) melts the plastic and extrudes it layer by layer to form the structural elements, which can also have cosmetic elements built in.
The lessons learnt from the project will inform 3D-printed house designs around the world.

Printing in the air

Objects built to fly need to be lightweight, strong and constructed to an exacting level of precision. These properties can readily be delivered by 3D printing, which is one reason the aerospace industry has been among the first to embrace the technology.
Airbus recently teamed up with German company Concept Laser to develop 3D-printed titanium parts, above, for its next generation A350 XWB passenger jet. One part is a complex fuel pipe that normally requires 10 individual components to be welded together. The 3D-printed version merged all 10 parts into one, no welding required. The end result is quicker to build, weighs less and costs only a fraction of the conventionally made part.

Origami and the laws of physics | sci-english.blogspot.com

A physicist’s take on an ancient art has provided new solutions for folding telescopes and airbags. By Jason England.

Origami and the laws of physics | sci-english.blogspot.com

It’s rare that an art form has enforceable rules. A sculptor is free to choose which material to use as well as the size of the finished piece. Painters are not told what to paint or which technique to use on the canvas. Indeed, the choice to paint on canvas is entirely theirs. Other arts may have established patterns, categories and forms, but rules are uncommon.
On the other hand, origami, the Japanese art of paper folding, is interesting because of its restrictions. Classic origami models should be created from a single sheet of paper – no cutting or gluing allowed. From this simple proposition a wonderful variety arises. Animals from antelope to zebra, human forms, musical instruments and even modern stealth aircraft have all been folded from one sheet. It is no wonder that origami has been called “an art of economy”.
The precise origins of origami are lost to history. Although paper was folded into a variety of shapes for use during ceremonies for the nobility and wealthy as early as the Heian period (794–1185 AD), what we would today consider “recreational origami” doesn’t appear to have developed until the middle of the 17th century, or possibly a little earlier. It took about 200 more years for what is arguably the first book on origami to appear. Sembazuru Orikata, or How to fold 1,000 cranes, was published in 1797. In the 20th century and now into the 21st, many modern origami masters emerged, but two deserve special mention.

Origami and the laws of physics | sci-english.blogspot.com

The first is Yoshizawa Akira. Yoshizawa is widely considered to have been the “grandmaster of origami”. He created tens of thousands of original models, and is also responsible for the rebirth of the art in the 1950s. In addition to his beautiful designs, Yoshizawa created the diagramming system of dotted lines and arrows to indicate fold directions. This symbolic notation allows origami creators and folders to follow instructions without having to read Japanese – or any other language for that matter. The Yoshizawa system, with only minor adjustments and additions, is still in use. In 1983 Emperor Hirohito awarded Yoshizawa the Order of the Rising Sun – one of Japan’s highest honours – for his promotion of Japanese culture.

Lang’s creation of a realistic cuckoo clock made him a sensation.

The second modern master is Robert Lang. Trained as a physicist and engineer, Lang was introduced to origami at the age of six. By his early teens he was creating original designs. He continued his study of origami while at Stanford University and Caltech where he was awarded his PhD in applied physics. The combination of his scientific background and his love of origami has enabled him to develop amazing designs and techniques. Just 40 years ago virtually all origami had the same stylised form it had at the turn of the century. No one would have confused an origami insect with the real thing. In fact, before the 1990s, few folders even attempted to create insects, as it was considered far too difficult to achieve any satisfactory realism with them. Lang certainly disproved that. With the advent of computer-aided designs and through the efforts of Lang and a few other artists, the traditional art form began to allow for hyper-realistic insects, crustaceans, and spiders to be folded, as well as hundreds of other designs formerly dismissed as impossible.
Lang’s creation of a realistic cuckoo clock from a single sheet of paper in the late 1980s made him a sensation in the origami world. It was just one of many innovations and discoveries on his part. Leaving his job as a physicist at NASA’s Jet Propulsion Labs in 2001, Lang devoted himself full time to origami, but didn’t entirely remove himself from the world of science; he continues to be involved in engineering and science through his origami research.
Lang has consulted with automobile safety equipment manufacturers on the optimal way to stow air bags, worked with members of Lawrence Livermore National Laboratory on the best way to fit a 30-metre optical telescope into a rocket body without creasing the fragile lens membrane, and designed a sterile medical instrument pouch that can be opened without being contaminated.
With the confluence of maths and origami not yet 30 years old, Lang believes that continued research into the art will have even more to offer.

Is gravity the force driving time forwards? | sci-english.blogspot.com

Is gravity the force driving time forwards? |sci-english.blogspot.com

A new theory seeks to explain the so-called arrow of time and why it travels in one direction. Dan Falk reports.

It’s obvious that time flows in one direction. A teacup falls to the floor and shatters but we never see the broken shards reassemble; scramble an egg and it will never unscramble; we get older not younger with each passing day.
It might seem less obvious to ask: why does our Universe have an arrow of time?  But physicists and philosophers have asked, and struggled with this question, at least since the days of Aristotle. So whenever a new theory comes along, the scientific community greets it with great caution. Nevertheless, a paper in Physical Review Letters last October, by Flavio Mercati at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, and his colleagues, has made physicists sit up and take notice. Mercati believes he can demonstrate that the most familiar of nature’s forces – gravity – is what sets time ticking in a certain direction.
At first glance, gravity isn’t an obvious place to look for clues about time. There’s nothing in the mathematics of gravity to suggest why time would flow in a particular direction.  Instead, physicists have looked to the second law of thermodynamics to explain why breaking a teacup or scrambling an egg are irreversible processes. The second law says that the amount of disorder in a closed system – what physicists call entropy – steadily increases over time. It tells you that if you have a highly ordered “low-entropy” system now, you can expect to have a high-entropy system in the future. Tidy your house on Sunday, and you can be sure it will be messy by the end of the week.
But how did our Universe end up in its low-entropy, highly ordered state?
“The question we might have made some tiny progress on is: Why was the teacup, or the egg, in this low entropy state in the first place?” says Mercati.

'To understand the arrow of time, we don’t need
to worry about the initial conditions of the Universe'

It was the British physicist Roger Penrose, back in the 1970s, who first drew attention to the second law’s shortcomings as a way to define time’s arrow. According to the law, our Universe ought to appear more and more ordered as we turn back the clock – but our understanding of the early Universe shows the opposite. Immediately after the Big Bang it was a hot plasma of fundamental particles like protons and electrons – a very scrambled egg, so to speak.
Mercati and his colleagues, Tim Kowlowski of the University of New Brunswick and independent British physicist Julian Barbour, offer new thinking on the problem. Their paper “Identification of a Gravitational Arrow of Time,” argues that to understand the arrow of time, we don’t need to worry about the initial conditions of the Universe; instead, they believe gravity can explain the phenomenon by itself. Few scientists had pursued this path because gravity says nothing about time; its equations are time-symmetric. To get a feel for this, imagine a film of a planet orbiting the sun.  Now imagine playing the film backwards. Unlike a scrambled egg unscrambling itself, which shows a change from disorder to order, the planet-film would look much the same projected backwards as forwards – except that the planet would move in the opposite direction.
To explore how gravity might explain the problem of time, they modelled its effects on a simple version of the Universe, a “toy model”, in which an array of 1,000 particles are arranged randomly in virtual space, and allowed to move in response to gravity alone. They found that the particles inevitably reach a point where they’re tightly clumped together; after that, they move further apart.  It’s a one-way process – there’s no going back to the clumped state.
Interestingly, the complexity of the system – defined in a precise way – grows, even as the system becomes less tightly clumped. Their definition of complexity was related to the space between the particles: roughly the ratio between the maximum and minimum  distances. Defined in this way, the complexity is lowest when  the particles are most tightly clumped, and grows as the system evolves and spreads out.
The toy model achieves a fair facsimile of the way our Universe moved spontaneously from a state of low complexity – the plasma – to a state of high complexity: galaxies, stars, planets, and so forth.  The arrow of time, they argue, follows from this natural increase in complexity.
The team’s argument is not an alternative to the second law of thermodynamics, but a complement to it. Gravity, says Mercati, “creates the conditions for having eggs that you can scramble in the first place”. So the second law explains the irreversible shattering of teacups, but the clumping power of gravity explains the creation of the ordered conditions in which complex structures – eggs, teacups, human beings – can form at all.  

'Overall, it’s no surprise to learn that the Universe gets more complex with time.'

Mercati and his colleagues’ work certainly won’t be the last word on time’s arrow – but it’s a welcome step forward, according to physicist Paul Davies, author of About Time and many other popular physics books. “Overall, it’s no surprise to learn that the Universe gets more complex with time,” he says. “But it’s very hard to pin down in any mathematical way that that is in fact the case. So this model is very welcome. One toy model that demonstrates something very clearly is worth a thousand hand-wavy descriptions.”
Physicist Sean Carroll of Caltech, who tackled the arrow of time by a different method with colleague Jennifer Chen about a decade ago, is also pleased with Mercati’s result. “They worked out an explicit model, where you can solve the equations, which is always a good thing to do,” he says.
The team’s model still has room for refinement. The model uses only simple Newtonian gravity; it ignores Einstein’s more complete theory, known as general relativity. It also ignores quantum theory. Further insight will come, Mercati speculates, when we have a framework that combines these two approaches – the long-sought quantum theory of gravity.
“The feeling that we’re missing something – that’s the real drive behind physics,” says Mercati. “If we felt that everything was in place, and that there were only a few details to fill in, I’d be much less interested in it.”

Dan Falk is a science journalist based in Toronto.

Fermi Detects Hints of Starquakes in Magnetar ‘Storm’ | sci-english.blogspot.com

A rupture in the crust of a highly magnetized neutron star, shown here in an artist’s rendering, can trigger high-energy eruptions. Fermi observations of these blasts include information on how the star’s surface twists and vibrates, providing new insights into what lies beneath | sci-english.blogspot.com

Using data from NASA’s Fermi Gamma-ray Space Telescope, astronomers have discovered underlying signals related to the rapid-fire “storm” of high-energy blasts detected in 2009 from a highly magnetized neutron star.
Such signals were first identified during the fadeout of rare giant flares produced by magnetars. Over the past 40 years, giant flares have been observed just three times — in 1979, 1998 and 2004 — and signals related to starquakes, which set the neutron stars ringing like a bell, were identified only in the two most recent events.
“Fermi’s Gamma-ray Burst Monitor (GBM) has captured the same evidence from smaller and much more frequent eruptions called bursts, opening up the potential for a wealth of new data to help us understand how neutron stars are put together,” said Anna Watts, an astrophysicist at the University of Amsterdam in the Netherlands and co-author of a new study about the burst storm. “It turns out that Fermi’s GBM is the perfect tool for this work.”
In the midst of SGR J1550-5418’s 2009 burst storm, Swift’s X-Ray Telescope captured an expanding halo produced by the magnetar’s brightest bursts. The rings formed as X-rays from the brightest bursts scattered off of intervening dust clouds. Clouds closer to Earth produced larger rings. Image Credit: NASA/Swift/Jules Halpern, Columbia University
Neutron stars are the densest, most magnetic and fastest-spinning objects in the universe that scientists can observe directly. Each one is the crushed core of a massive star that ran out of fuel, collapsed under its own weight, and exploded as a supernova. A neutron star packs the equivalent mass of half-a-million Earths into a sphere about 12 miles across, roughly the length of Manhattan Island in New York City.
While typical neutron stars possess magnetic fields trillions of times stronger than Earth’s, the eruptive activity observed from magnetars requires fields 1,000 times stronger still. To date, astronomers have confirmed only 23 magnetars.
Because a neutron star’s solid crust is locked to its intense magnetic field, a disruption of one immediately affects the other. A fracture in the crust will lead to a reshuffling of the magnetic field, or a sudden reorganization of the magnetic field may instead crack the surface. Either way, the changes trigger a sudden release of stored energy via powerful bursts that vibrate the crust, a motion that becomes imprinted on the burst’s gamma-ray and X-ray signals.
It takes an incredible amount of energy to convulse a neutron star. The closest comparison on Earth is the 9.5-magnitude Chilean earthquake of 1960, which ranks as the most powerful ever recorded on the standard scale used by seismologists. On that scale, said Watts, a starquake associated with a magnetar giant flare would reach magnitude 23.
The 2009 burst storm came from SGR J1550−5418, an object discovered by NASA’s Einstein Observatory, which operated from 1978 to 1981. Located about 15,000 light-years away in the constellation Norma, the magnetar was quiet until October 2008, when it entered a period of eruptive activity that ended in April 2009. At times, the object produced hundreds of bursts in as little as 20 minutes, and the most intense explosions emitted more total energy than the sun does in 20 years. High-energy instruments on many spacecraft, including NASA’s Swift and Rossi X-ray Timing Explorer, detected hundreds of gamma-ray and X-ray blasts.
Speaking at the Fifth Fermi International Symposium in Nagoya, Japan, on October 21, Watts said the new study examined 263 individual bursts detected by Fermi’s GBM and confirms vibrations in the frequency ranges previously seen in giant flares. “We think these are likely twisting oscillations of the star where the crust and the core, bound by the super-strong magnetic field, are vibrating together,” she explained. “We also found, in a single burst, an oscillation at a frequency never seen before and which we still do not understand.”
A key element of the research is a new analysis technique developed by University of Amsterdam researcher Daniela Huppenkothen. Normally scientists search for oscillations in high-energy data by looking for variations aligned to a particular frequency. Such methods are best suited for finding a strong signal with little competition rather than a faint signal immersed in a bright and rapidly changing environment, such as a burst.
Huppenkothen likens the problem to detecting ripples from a stone tossed into a quiet pond. “Now imagine you’re in the middle of the North Atlantic during a storm, searching for those ripples amidst huge waves in a churning sea,” she explained. “Our old methods really weren’t appropriate for this, but I have in effect developed a way of accounting for the rough sea so we can find ripples even in stormy conditions.”
While there are many efforts to describe the interiors of neutron stars, scientists lack enough observational detail to choose between differing models. Neutron stars reach densities far beyond the reach of laboratories and their interiors may exceed the density of an atomic nucleus by as much as 10 times. Knowing more about how bursts shake up these stars will give theorists an important new window into understanding their internal structure.
“Right now,” added Watts, “we are waiting for more bursts — and if we’re lucky, a giant flare — to take advantage of GBM’s excellent capabilities.”
Publications:

• D. Huppenkothen, et al., “Quasi-periodic Oscillations in Short Recurring Bursts of the Soft Gamma Repeater J1550–5418,” 2014, ApJ, 787, 128; doi:10.1088/0004-637X/787/2/128
• Daniela Huppenkothen, et al., “Quasi-Periodic Oscillations and Broadband Variability in Short Magnetar Bursts,” 2013, ApJ, 768, 87; doi:10.1088/0004-637X/768/1/87

PDF Copies of the Studies:

• Quasi-Periodic Oscillations and broadband variability in short magnetar bursts
• Quasi-Periodic Oscillations in Short Recurring Bursts of the Soft-Gamma Repeater J1550-5418

Source: Francis Reddy, NASA’s Goddard Space Flight Center
Image: NASA’s Goddard Space Flight Center/S. Wiessinger

Feathers in flight inspire anti-turbulence technology | sci-english.blogspot.com

The prototype anti-turbulence system developed at RMIT University, in wind tunnel tests | sci-english.blogspot.com

Inspired by nature's own anti-turbulence devices -- feathers -- researchers have developed an innovative system that could spell the end of turbulence on flights.

Researchers from the Unmanned Systems Research Team at RMIT University in Melbourne, Australia, have lodged a provisional patent on the system, which mimics the way feathers help birds detect disturbances in the air.
Research supervisor Professor Simon Watkins, said flight testing on a micro plane showed the system significantly reduced the effects of turbulence.
"By sensing gusts and disturbances in air flow through their feathers, birds are able to fly gracefully rather than bouncing around in turbulent air," he said.
"The system we have developed replicates this natural technology, with the aim of enabling planes to fly smoothly through even severe turbulence -- just like birds."
The system is based on the concept of phase-advanced sensing, in which flow disturbance is sensed before it results in aircraft movement.
This can be achieved by early sensing of the pressures from gust effects on the leading parts of the wing or by measuring the gusts ahead of the wing.
Professor Watkins said the system had great potential for all sizes of aircraft and could not only reduce the effects of turbulence on passengers but also reduce loads on plane wings, leading to lower fatigue and hence longer life.
"While we need to explore new sensor arrangements to apply this technology to larger and faster aircraft, we have proven the idea on the most challenging problem of keeping small, lightweight planes steady -- since these are the ones that get bounced around the most," he said.
The patent submission for a turbulence mitigation system for aircraft represents the successful outcome of PhD research by Abdulghani Mohamed, supervised by Professor Watkins and Dr Reece Clothier in RMIT's School of Aerospace, Mechanical and Manufacturing Engineering.
Mr Mohamed's theoretical contributions in the field of turbulence and its effects on flight vehicles, aided the development of this invention.
Video: http://www.youtube.com/watch?v=uflUmBbdaAo&feature=youtu.be

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Story Source:
The above story is based on materials provided by RMIT University. Note: Materials may be edited for content and length.

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Journal Reference:

1. A. Mohamed, S. Watkins, R. Clothier, M. Abdulrahim, K. Massey, R. Sabatini. Fixed-wing MAV attitude stability in atmospheric turbulence—Part 2: Investigating biologically-inspired sensors. Progress in Aerospace Sciences, 2014; 71: 1 DOI: 10.1016/j.paerosci.2014.06.002

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Extreme gravity effects revealed by oxygen for the first time in neutron star that 'eats' white dwarf | sci-english.blogspot.com

Neutron star 'eats' oxygen-rich white dwarf in a peculiar binary system | sci-english.blogspot.com

Astronomers from SRON Netherlands Institute for Space Research and Utrecht University have found blurred oxygen signatures in the X-rays from a neutron star that 'eats' a white dwarf. For the first time the effects of extreme gravity are revealed by oxygen instead of iron atoms.

Although strong gravity near neutron stars and black holes has been studied before in a similar way, this result is unique. Until now, only blurred X-ray signatures of iron atoms have been observed in the X-rays from a neutron star. However, the characteristics of these so called 'iron lines' are disputed, which makes them less suited for extreme gravity field measurements.
The neutron star has been studied before but now Oliwia Madej, PhD student at Utrecht University and SRON Netherlands Institute for Space Research, has found blurred oxygen signatures in the X-rays from the star. She made this discovery in an archival observation performed by ESA's XMM-Newton observatory, which is equipped with the SRON reflection grating spectrometer (RGS) that is extemely sensitive in these particular wavelenghts. The research was carried out under supervision of SRON-researcher Peter Jonker.
The neutron star that the astronomers observed is part of a binary system called 4U 0614+091. In the binary, the neutron star and a white dwarf closely orbit each other in roughly 50 minutes. The white dwarf -- basically a burnt out star -- orbits at such a small distance from the neutron star that the oxygen-rich gas is pulled off the dwarf and starts closely swirling around the neutron star in a disk.
Extreme gravity
"Normally, hot oxygen atoms emit X-rays at a specific energy," Madej explains. "But because of the extreme gravity and the hot gas in the disk around the neutron star, this oxygen signature in the X-ray data is blurred." From the shape of the blur Madej tried to estimate the inner radius of the oxygen-rich disk around the neutron star, which should give an idea of the maximum radius that the neutron star could possibly have.
"Unfortunately, the current data are not yet good enough to give a definitive answer on the size of a neutron star," Peter Jonker admits. "To determine this in greater detail we need more observation time. And when we find the signature of iron molecules as well, we can now compare the characteristics of the two emission lines. Measured together, uncertainties about the measurements of the iron line can be taken away, which will guide the interpretation in other systems where only iron has been seen. All in all our observations are definitely an important step on the way towards a better understanding of the extreme conditions around and inside a neutron star."
Neutron stars -- shaped out of the collapsing cores of massive stars -- are the most compact objects with a surface in the universe. A neutron star has a slightly higher mass compared to a white dwarf, but the matter is squeezed into a ball of only 10-20 km in diameter. At these high densities, normal atoms cannot exist anymore. Anything denser would collapse into a black hole. Therefore, astronomers are very interested in the state of the matter inside a neutron star.
The results of the research appear in the Monthly Notices of the Royal Astronomical Society.

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Story Source:
The above story is based on materials provided by SRON Netherlands Institute for Space Research. Note: Materials may be edited for content and length.

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Journal Reference:

1. O.K. Madej, P.G. Jonker, A.C. Fabian, C. Pinto, F. Verbunt, J. de Plaa. A relativistically broadened O VIII Lyalpha line in the ultra-compact X-ray binary 4U 0614 091. Monthly Notices of the Royal Astronomical Society, 2010; (accepted for publication) [link]

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Extending Einstein's theory beyond light speed | sci-english.blogspot.com

Researchers have extended Einstein’s theory of special relativity to work beyond the speed of light | sci-english.blogspot.com

University of Adelaide applied mathematicians have extended Einstein's theory of special relativity to work beyond the speed of light.

Einstein's theory holds that nothing could move faster than the speed of light, but Professor Jim Hill and Dr Barry Cox in the University's School of Mathematical Sciences have developed new formulas that allow for travel beyond this limit.
Einstein's Theory of Special Relativity was published in 1905 and explains how motion and speed is always relative to the observer's frame of reference. The theory connects measurements of the same physical incident viewed from these different points in a way that depends on the relative velocity of the two observers.
"Since the introduction of special relativity there has been much speculation as to whether or not it might be possible to travel faster than the speed of light, noting that there is no substantial evidence to suggest that this is presently feasible with any existing transportation mechanisms," said Professor Hill.
"About this time last year, experiments at CERN, the European centre for particle physics in Switzerland, suggested that perhaps neutrinos could be accelerated just a very small amount faster than the speed of light; at this point we started to think about how to deal with the issues from both a mathematical and physical perspective.
"Questions have since been raised over the experimental results but we were already well on our way to successfully formulating a theory of special relativity, applicable to relative velocities in excess of the speed of light.
"Our approach is a natural and logical extension of the Einstein Theory of Special Relativity, and produces anticipated formulae without the need for imaginary numbers or complicated physics."
The research has been published in the Proceedings of the Royal Society A in a paper, 'Einstein's special relativity beyond the speed of light'. Their formulas extend special relativity to a situation where the relative velocity can be infinite, and can be used to describe motion at speeds faster than light.
"We are mathematicians, not physicists, so we've approached this problem from a theoretical mathematical perspective," said Dr Cox. "Should it, however, be proven that motion faster than light is possible, then that would be game changing.
"Our paper doesn't try and explain how this could be achieved, just how equations of motion might operate in such regimes."

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Story Source:
The above story is based on materials provided by University of Adelaide. Note: Materials may be edited for content and length.

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Journal Reference:

1. J. M. Hill, B. J. Cox. Einstein's special relativity beyond the speed of light. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012; DOI: 10.1098/rspa.2012.0340

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