A burial of a young woman found in the middle of a tomb. Analysis of her skeletal remains reveal that she suffered dental problems, including tooth loss. At one point in her life she suffered an internal hemorrhage in the meninges of her cranium. ...
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Excerpt from bulletinstandard.com A pair of pictures of a young star, produced 18 years apart, has revealed a dramatic distinction that is giving astronomers with a exclusive, "real-time" appear at how enormous stars create in the e...
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Buck Rogers, Staff WriterWaking TimesDuring the cold war era the Soviet Union and the United States were locked in an arms and technology race, each nation wanting to prove their dominance over the other, each striving to be the next reigning superpower in a world still shattered by the second world war. The Soviet’s took the lead when in April of 1961, cosmonaut Yuri Gagarin successfully orbited the earth and returned home safely. In May, president John F. Kennedy ma [...]
Excerpt from autotrader.com By Josh Sadlier Seems like the only thing automakers want to talk about these days is how their cars suddenly get great fuel economy. Given this relentless chatter, it's tempting to conclude that mos...
(Reuters) - A 2.8-million-year-old jawbone fossil with five intact teeth unearthed in an Ethiopian desert is pushing back the dawn of humankind by about half a million years.Scientists said on Wednesday the fossil represents the oldest known repres...
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| The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider. In this image two high-energy photons collide. The yellow lines are the measured tracks of other particles produced in the collision, which helped lead to the discovery of the God particle. |
Excerpt from dailymail.co.uk
- God Particle is believed to be responsible for all the mass in the universe
- Particle was discovered in 2012 using a Cern's supercollider in Geneva
- uperconductor experiment suggests the particle could be detected without the huge amounts of energy used at by the Large Hadron Collider
- LHC is due to come back online next month after an upgrade that has given it a big boost in energy
Scientists have discovered a simulated version of the elusive 'God particle' using superconductors.
The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider.
The results could help scientists better understand how this mysterious particle – also known as the Higgs boson – behaves in different conditions.
'Just as the Cern experiments revealed the existence of the Higgs boson in a high-energy accelerator environment, we have now revealed a Higgs boson analogue in superconductors,' said researcher Aviad Frydman from Bar-Ilan University.
Superconductors are a type of metal that, when cooled to low temperatures, allow electrons to pass through freely.
'The Higgs mode was never actually observed in superconductors because of technical difficulties - difficulties that we've managed to overcome,' Professor Frydman said.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider (pictured)
WHAT IS THE GOD PARTICLE?
The 'God Particle', also known as the Higgs boson, was a missing piece in the jigsaw for physicists in trying to understand how the universe works.
Scientists believe that a fraction of a second after the Big Bang that gave birth to the universe, an invisible energy field, called the Higgs field, formed.
This has been described as a kind of 'cosmic treacle' across the universe.
As particles passed through it, they picked up mass, giving them size and shape and allowing them to form the atoms that make up you, everything around you and everything in the universe.
This was the theory proposed in 1964 by former grammar school boy Professor Higgs that has now been confirmed.
Without the Higgs field particles would simply whizz around space in the same way as light does.
A boson is a type of sub-atomic particle. Every energy field has a specific particle that governs its interaction with what's around it.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, they should have left a recognisable footprint. This footprint was found in 2012.
The main difficulty was that the superconducting material would decay into something known as particle-hole pairs.
Large amounts of energy – which are usually needed to excite the Higgs mode - tend to break apart the electron pairs that act as the material's charge.
Professor Frydman and his colleagues solved this problem by using ultra-thin superconducting films of Niobium Nitrite (NbN) and Indium Oxide (InO) as something known as the 'superconductor-insulator critical point.'
This is a state in which recent theory predicted the decay of the Higgs would no longer occur.
In this way, they could still excite a Higgs mode even at relatively low energies.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt,' Professor Frydman added.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The different approach help solve one of the longstanding mysteries of fundamental physics.
The discovery of the Higgs boson verified the Standard Model, which predicted that particles gain mass by passing through a field that slows down their movement through the vacuum of space.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, the also left a recognisable footprint.
Professor Higgs, 83, has been waiting since 1964 for science to catch up with his ideas about the Higgs boson
According to Professor Frydman, observation of the Higgs mechanism in superconductors is significant because it reveals how a single type of physical process behaves under different energy conditions.
'Exciting the Higgs mode in a particle accelerator requires enormous energy levels - measured in giga-electronvolts, or 109 eV,' Professor Frydman says.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The LHC is due to come back online in March after an upgrade that has given it a big boost in energy.
'With this new energy level, the (collider) will open new horizons for physics and for future discoveries,' CERN Director General Rolf Heuer said in a statement.
'I'm looking forward to seeing what nature has in store for us.'
Cern's collider is buried in a 27-km (17-mile) tunnel straddling the Franco-Swiss border at the foot of the Jura mountains.
The LHC in Geneva will come back online in March after an upgrade that has given it a big boost in energy
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| This artist's illustration depicts the furious cosmic winds streaming out from a monster supermassive black hole as detected by NASA's NuSTAR space telescope and the European Space Agency's XMM-Newton X-ray observatory. |
Except from space.com
A ravenous, giant black hole has belched up a bubble of cosmic wind so powerful that it could change the fate of an entire galaxy, according to new observations.
Researchers using two X-ray telescopes have identified a cosmic wind blowing outward from the supermassive black hole at the center of galaxy PDS 456. Astronomers have seen these winds before, but the authors of the new research say this is the first observation of a wind moving away from the center in every direction, creating a spherical shape.
The wind could have big implications for the future of the galaxy: It will cut down on the black hole's food supply, and slow star formation in the rest of the galaxy, the researchers said. And it's possible that strong cosmic winds are a common part of galaxy evolution — they could be responsible for turning galaxies from bright, active youngsters to quiet middle-agers.
Big eater
The supermassive black hole at the center of PDS 456 is currently gobbling up a substantial amount of food: A smorgasbord of gas and dust surrounds the black hole and is falling into the gravitational sinkhole.As matter falls, it radiates light. The black hole at the center of PDS 456 is devouring so much matter, that the resulting radiation outshines every star in the galaxy. These kinds of bright young galaxies are known as quasars: a galaxy with an incredibly bright center, powered by a supermassive black hole with a big appetite.
New observations of PDS 456 have revealed a bubble of gas moving outward, away from the black hole. Using NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) and ESA’s (European Space Agency) XMM-Newton, the authors of the new research imaged the galaxy on five separate occassions in 2013 and 2014. The researchers say they can show that the photons of light emitted by the in-falling matter are pushing on nearby gas, creating the wind.
Scientists have studied these cosmic winds before, but the authors of the new research say their work goes a step further.
"It tells us that the shape of the wind is not just a narrow beam pointed in our direction. It is really a wind that is flowing in every direction away from the black hole," said Emanuele Nardini, a postdoctoral researcher at Keele University in Staffordshire, England. "With a spherical wind, the amount of mass it carries out is much larger than just a narrow beam."
According to a statement from NASA, galaxy PDS 456 "sustains winds that carry more energy every second than is emitted by more than a trillion suns." Such powerful winds could change the entire landscape of PDS 456, the researchers say. First, the wind will blow through the disk of matter surrounding the black hole — this disk currently serves as the black hole's food supply. The cosmic wind created by the black hole's appetite could significantly reduce or destroy the disk. In other words, the black hole cannot have its cake and eat it, too.
Bright young things
With no matter left to fall into the black hole, the radiation would cease as well. The brilliant center of the quasar will dim. By diminishing the black hole's food supply, they may turn quasars and other "active galaxies" like PDS 456 into quiescent galaxies like the Milky Way. Theorists have proposed that cosmic winds could explain why there are more young active galaxies than old active galaxies."We know that in almost every galaxy, a supermassive black hole resides in the center," said Nardini. "But, most of the galaxies we see today are quiescent, they are not active in any way. The fact that galaxies today are quiescent — we have to find an explanation for that in something that happened a long time ago."
In addition to quenching the radiation from an active black hole, these cosmic winds may slow down star formation in galaxies. The cosmic wind could blow through regions thick with gas and dust, where young stars form, and thin out the fertile stellar soil.
"If you have a black hole with this kind of wind, in millions of years [the winds] will be able to quench star formation and create a galaxy like our own," Nardini said. Stars will still form in the Milky Way, but not at the high rate of many young galaxies.
It's possible that these cosmic winds are a central reason why most galaxies go from being brightly burning active youngsters to quiet middle-agers.
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| WinSun claims that their new 3D printed five-story building is the tallest of its kind in the world. |
Excerpt from
Back in April, a team of Chinese construction workers used a 3D printer to construct houses. By day’s end, there were 10 standing. They were compact and fairly bare bones — nothing much to look at besides the “wow!” factor of there being as many as — count them — 10. But this time around, those same builders have taken the wraps off an achievement that’s roundly more impressive.
In Suzhou Industrial Park, adjacent to Shanghai, stands a five-story structure that the WinSun Decoration Design Engineering firm claims is “the world’s tallest 3D-printed building.” Next to it is the equally massive 3D-printed mansion, which measures 11,840 square feet. Like the previous buildings, the walls are comprised of a mix of concrete and recycled waste materials, such as glass and steel, and formed layer by printed layer. The company stated that the total cost for the mansion was roughly $161,000.
In a broader sense, this latest feat is yet another indication of how rapidly additive manufacturing techniques are advancing. Once used primarily as a means to quickly render miniature model versions of products, the technology has reached a point where large-scale printers are now capable of making life-sized working creations, such as automobiles, in mere days. For instance, it took less than 48 hours for start-up Local Motors to print a two-seater called the Strati into existence and drive it off the showroom.
Many of these designs, however, typically don’t amount to much beyond being passion projects meant to push 3D printing into new frontiers and drum up some publicity along the way. One example of this is the massive 3D Print Canal House that’s being constructed entirely on-site along a canal in Amsterdam, a process that’s slated to take longer and is less feasible than standard construction, Phil Reeves of UK-based 3D printing research firm Econolyst recently told CNN.
More promising, though, is a system developed by Behrokh Khoshnevis, a University of Southern California engineering professor. His concept machine, called Contour Crafting, involves a clever combination of mechanical cranes and 3D layering to print and assemble entire homes simultaneously — complete with insulation and indoor plumbing — in less than a day.
The approach employed by WinSun isn’t anywhere near that level of sophistication, but it may well prove to be the most practical – at least thus far. There is some labor and equipment costs that comes from trucking in and piecing together the various sections on-site, though the manner in which it all comes together is comparable to the ease of prefab assembly. It’s also reportedly greener thanks to the addition of recycled materials.
To pitch the advantages of their technology, the company held a news conference to announce that they had taken on orders for 20,000 smaller units as well as highlight some significant cost-cutting figures. According toindustry news site 3Der:
The sheer size of the printer allows for a 10x increase in production efficiency. WinSun estimates that 3D printing technology can save between 30 and 60 percent of building materials and shortens production times by 50 to even 70 percent, while decreasing labor costs by 50 up to even 80 percent. Future applications include 3D printed bridges or tall office buildings that can be built right on site.
WinSun did not respond to a request to disclose how they arrived at those numbers, but Enrico Dini, an Italian civil engineer and chairman of competing start-up Monolite, says that he suspects the calculations may be a tad bit inflated. Still, he emphasized that his own data does back up the claim that, compared to conventional methods, layering may boost overall efficiency.
“It would be very difficult to fabricate such large sections with traditional concrete casting,” he says. “With 3D printing, you have a lot less waste because you’re only printing out as much material as you need and you can custom shape whole sections on the spot, which can be a big challenge.”
WinSun’s 3D-printed villa has several rooms and has been deemed to be up to China’s national safety standards.
One major concern is whether these large-scale dwellings can hold up over time against the elements. According to 3Der, Ma Rongquan, chief engineer of China Construction Bureau, inspected the building’s structural integrity and found them to be up to code, but was careful to note that state officials have yet to establish specific criteria for assessing the long-term safety of 3D printed architecture.
And as Dini, who supports the technology, points out, there is the possibility that the use of additive manufacturing may pose some degree of risk. “The only issue is that as the layers of concrete are bonded together, they’re drying at slightly different rates and that’s not very ideal,” he explains. “So there’s maybe a higher chance of it fracturing at the contact point if there’s a strong enough force at play.”
Regardless, Dini says he’d feel completely safe going inside any floor of either building since construction materials used today are likely to contain special additives to enhance strength and resistance. One such formulation, fiber-reinforced Ductal, has been shown in some tests to be 10 times stronger and last twice as long as regular concrete. He stressed that walls should also be tested to ensure that other properties, such as acoustics, ventilation and thermal insulations are on par with existing buildings.
“In Italy, building standards are extremely strict,” he noted. “But I can’t say I can say the same about China.”
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At the center of spiral galaxy M81 is a supermassive black hole about 70 million times more massive than our sun. |
Excerpt from insidescience.org
A physicist presents a solution to present-day cosmic mysteries.
By:
Nikodem Poplawski, Inside Science Minds Guest Columnist
(ISM) -- Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself.
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible "singularity," an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.
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| In this picture, spins in particles interact with spacetime and endow it with a property called "torsion." To understand torsion, imagine spacetime not as a two-dimensional canvas, but as a flexible, one-dimensional rod. Bending the rod corresponds to curving spacetime, and twisting the rod corresponds to spacetime torsion. If a rod is thin, you can bend it, but it's hard to see if it's twisted or not. |
The first is general relativity, the modern theory of gravity. It describes the universe at the largest scales. Any event in the universe occurs as a point in space and time, or spacetime. A massive object such as the Sun distorts or "curves" spacetime, like a bowling ball sitting on a canvas. The Sun's gravitational dent alters the motion of Earth and the other planets orbiting it. The sun's pull of the planets appears to us as the force of gravity.
The second is quantum mechanics, which describes the universe at the smallest scales, such as the level of the atom. However, quantum mechanics and general relativity are currently separate theories; physicists have been striving to combine the two successfully into a single theory of "quantum gravity" to adequately describe important phenomena, including the behavior of subatomic particles in black holes.
A 1960s adaptation of general relativity, called the Einstein-Cartan-Sciama-Kibble theory of gravity, takes into account effects from quantum mechanics. It not only provides a step towards quantum gravity but also leads to an alternative picture of the universe. This variation of general relativity incorporates an important quantum property known as spin. Particles such as atoms and electrons possess spin, or the internal angular momentum that is analogous to a skater spinning on ice.
Spacetime torsion would only be significant, let alone noticeable, in the early universe or in black holes. In these extreme environments, spacetime torsion would manifest itself as a repulsive force that counters the attractive gravitational force coming from spacetime curvature. As in the standard version of general relativity, very massive stars end up collapsing into black holes: regions of space from which nothing, not even light, can escape.
Here is how torsion would play out in the beginning moments of our universe. Initially, the gravitational attraction from curved space would overcome torsion's repulsive forces, serving to collapse matter into smaller regions of space. But eventually torsion would become very strong and prevent matter from compressing into a point of infinite density; matter would reach a state of extremely large but finite density. As energy can be converted into mass, the immensely high gravitational energy in this extremely dense state would cause an intense production of particles, greatly increasing the mass inside the black hole.
The increasing numbers of particles with spin would result in higher levels of spacetime torsion. The repulsive torsion would stop the collapse and would create a "big bounce" like a compressed beach ball that snaps outward. The rapid recoil after such a big bounce could be what has led to our expanding universe. The result of this recoil matches observations of the universe's shape, geometry, and distribution of mass.
In turn, the torsion mechanism suggests an astonishing scenario: every black hole would produce a new, baby universe inside. If that is true, then the first matter in our universe came from somewhere else. So our own universe could be the interior of a black hole existing in another universe. Just as we cannot see what is going on inside black holes in the cosmos, any observers in the parent universe could not see what is going on in ours.
The motion of matter through the black hole's boundary, called an "event horizon," would only happen in one direction, providing a direction of time that we perceive as moving forward. The arrow of time in our universe would therefore be inherited, through torsion, from the parent universe.
Torsion could also explain the observed imbalance between matter and antimatter in the universe. Because of torsion, matter would decay into familiar electrons and quarks, and antimatter would decay into "dark matter," a mysterious invisible form of matter that appears to account for a majority of matter in the universe.
Finally, torsion could be the source of "dark energy," a mysterious form of energy that permeates all of space and increases the rate of expansion of the universe. Geometry with torsion naturally produces a "cosmological constant," a sort of added-on outward force which is the simplest way to explain dark energy. Thus, the observed accelerating expansion of the universe may end up being the strongest evidence for torsion.
Torsion therefore provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe. It also appears as a remedy to several major problems of current theory of gravity and cosmology. Physicists still need to combine the Einstein-Cartan-Sciama-Kibble theory fully with quantum mechanics into a quantum theory of gravity. While resolving some major questions, it raises new ones of its own. For example, what do we know about the parent universe and the black hole inside which our own universe resides? How many layers of parent universes would we have? How can we test that our universe lives in a black hole?
The last question can potentially be investigated: since all stars and thus black holes rotate, our universe would have inherited the parent black hole’s axis of rotation as a "preferred direction." There is some recently reported evidence from surveys of over 15,000 galaxies that in one hemisphere of the universe more spiral galaxies are "left-handed", or rotating clockwise, while in the other hemisphere more are "right-handed", or rotating counterclockwise. In any case, I believe that including torsion in geometry of spacetime is a right step towards a successful theory of cosmology.
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| Planck has mapped the delicate polarisation of the CMB across the entire sky |
Excerpt from bbc.com
Scientists working on Europe's Planck satellite say the first stars lit up the Universe later than previously thought.
Earlier observations of this radiation had suggested the first generation of stars were bursting into life by about 420 million years after the Big Bang.
Planck's data indicates this great ignition was well established by some 560 million years after it all began.
"This difference of 140 million years might not seem that significant in the context of the 13.8-billion-year history of the cosmos, but proportionately it's actually a very big change in our understanding of how certain key events progressed at the earliest epochs," said Prof George Efstathiou, one of the leaders of the Planck Science Collaboration.
Subtle signal
The assessment is based on studies of the "afterglow" of the Big Bang, the ancient light called the Cosmic Microwave Background (CMB), which still washes over the Earth today.
Prof George Efstathiou: "We don't need more complicated explanations"
It contains a wealth of information about early conditions in the Universe, and can even be used to work out its age, shape and do an inventory of its contents.
Scientists can also probe it for very subtle "distortions" that tell them about any interactions the CMB has had on its way to us.
Forging elements
One of these would have been imprinted when the infant cosmos underwent a major environmental change known as re-ionisation.
Prof Richard McMahon: "The two sides of the bridge now join"
These hot giants would have burnt brilliant but brief lives, producing the very first heavy elements. But they would also have "fried" the neutral gas around them - ripping electrons off the hydrogen protons.
And it is the passage of the CMB through this maze of electrons and protons that would have resulted in it picking up a subtle polarisation.
Impression: The first stars would have been unwieldy behemoths that burnt brief but brilliant lives The Planck team has now analysed this polarisation in fine detail and determined it to have been generated at 560 million years after the Big Bang.
The American satellite WMAP, which operated in the 2000s, made the previous best estimate for the peak of re-ionisation at 420 million years.
The problem with that number was that it sat at odds with Hubble Space Telescope observations of the early Universe.
Hubble could not find stars and galaxies in sufficient numbers to deliver the scale of environmental change at the time when WMAP suggested it was occurring.
Planck's new timing "effectively solves the conflict," commented Prof Richard McMahon from Cambridge University, UK.
"We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the 'now side'.
"It's like a bridge being built over a river. The two sides do now join where previously we had a gap," he told BBC News.
That gap had prompted scientists to invoke complicated scenarios to initiate re-ionisation, including the possibility that there might have been an even earlier population of giant stars or energetic black holes. Such solutions are no longer needed.
No-one knows the exact timing of the very first individual stars. All Planck does is tell us when large numbers of these stars had gathered into galaxies of sufficient strength to alter the cosmic environment.
By definition, this puts the ignition of the "founding stars" well before 560 million years after the Big Bang. Quite how far back in time, though, is uncertain. Perhaps, it was as early as 200 million years. It will be the job of the next generation of observatories like Hubble's successor, the James Webb Space Telescope, to try to find the answer.
Being built now: The James Webb telescope will conduct a survey of the first galaxies and their stars
- Planck's CMB studies indicate the Big Bang was 13.8bn years ago
- The CMB itself can be thought of as the 'afterglow' of the Big Bang
- It spreads across the cosmos some 380,000 years after the Big Bang
- This is when the conditions cool to make neutral hydrogen atoms
- The period before the first stars is often called the 'Dark Ages'
- When the first stars ignite, they 'fry' the neutral gas around them
- These giants also forge the first heavy elements in big explosions
- 'First Light', or 'Cosmic Renaissance', is a key epoch in history
The new Planck result is contained in a raft of new papers just posted on the Esa website.
These papers accompany the latest data release from the satellite that can now be used by the wider scientific community, not just collaboration members.
Dr Andrew Jaffe: "The simplest models for inflation are ruled out"
It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.
What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.
"We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't."
Excerpt from space.com Over the next two weeks, you have an excellent chance to spot one of the most rarely observed objects in the sky, the zodiacal light. The zodiacal light takes its name from the ancient band of 12 constellations through which the...
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