Science and Discovery News

Discussion in 'News and Views' started by Allisiam, Oct 10, 2014.

  1. Allisiam

    Allisiam Well-Known Member

    Messages:
    504

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    Esther Inglis-Arkell




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    Han purple is an ancient pigment that wasn't reconstructed by modern chemists until 1992. After the chemists got done with it, it was the physicists' turn. Han purple, they found, eliminates an entire dimension. It makes waves go two-dimensional!

    The Chemistry of Han Purple

    You'll see Han purple on the famous terracotta warriors surrounding the tomb of the first emperor of China, or on ancient pottery and other works of art. Where you won't see it is on anything made between 220 A.D. and 1992, because after the pigment disappeared it took 1700 years to re-discover it. Elisabeth FitzHugh, a conservator at the Smithsonian, pinned down the chemical composition of the pigment and announced it was a barium copper silicate. (The paper describing the discovery is a fun read. It starts by pointing out the inferiority of other ancient purple pigments, which tended to be closer to red than purple. It also stresses that Tyrian purple, made from sea snails, was a textile dye, not a pigment, and that it could range anywhere from "reddish-blue to purplish-violet." Take that, Phoenicians!)

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    Exactly how some inventor stumbled on a way to make the pigment is still a matter of debate. An early theory, not believed by many, is that the Chinese learned how to make purple pigment from the Egyptians. Egyptian purple pigment seems to be similar, but the chemical formulas don't add up — Egyptians used calcium instead of barium. It's also not an easy process to pass from one culture to another. To get the elements to melt together, they have to be heated to about 850-1000 °C.

    Most researchers think that because it contains both silicon and barium Han purple was a by-product of the glass-making process. Barium makes glass shinier and cloudy, which means this pigment could be the work of early alchemists trying to synthesize white jade.

    Han Purple and the Third Dimension

    Barium copper-silicate doesn't just have archaeologists and chemists intrigued. At normal temperatures, it's an insulator and is nonmagnetic. Along with its many fine properties - prettiness, historical importance, a hint of aristocratic style — barium copper-silicat has many electrons, some of which spin up and some of which are spin down.

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    Something unusual happens as the temperature drops and as a magnetic field is applied, although the temperature has to drop pretty far, going down to between one and three degrees Kelvin, and the magnetic field has to be about 800,000 times the strength of Earth's magnetic field. The results are worth it — the electrons seem to merge, taking on one spin, and acting as one electron.

    That sounds like an ordinary superconductor, you say. Then you're as foolish as a Phoenician in sub-par purple! Han purple still has a trick up its sleeve. Drop the temperature some more and something happens to the magnetic wave traveling through the substance. At higher temperatures, it propagates like a regular wave, traveling in three dimensions. Get under one degree Kelvin, and it no longer has a vertical component. It propagates in two dimensions only.

    Scientists think that this has something to do with the structure of barium copper silicate. It's components are arranged like layers of tiles, so they don't stack up neatly. Each layers' tiles are slightly out of sync with the layer below them. This may frustrate the wave and force it to go two dimensional.
    Anyone wonder if ancient physicists discovered this? And if the secret to making Han purple was lost because they waved themselves into two dimensions?

    Terracotta Army Images: David Castor.
    [Via A Purple Barium Copper Silicate Pigment from Early China, Purple Reign, Raiders of the Lost Dimension, Dimensional Reduction at a Quantum Critical Point, 3-D Insulator Called Han Purple Loses a Dimension]
     
  2. Allisiam

    Allisiam Well-Known Member

    Messages:
    504
    Crows count on 'number neurons'

    Date:
    June 8, 2015
    Source:
    Universitaet Tübingen
    Summary:
    Neurobiologists have discovered cells in the crow brain that respond to a specific number of items. The study provides valuable insights into the biological roots of counting capabilities. What makes this finding even more interesting is that a long evolutionary history separates us from birds; as a consequence, the brains of crows and humans are designed very differently.
    FULL STORY

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    Crows recognized the number of dots shown in computer displays. Tübingen researchers discovered ‘number neurons’ in the crow’s end-brain that responded to a specific number of items.
    Credit: Andreas Nieder


    An old story says that crows have the ability to count. Three hunters go into a blind situated near a field where watchful crows roam. They wait, but the crows refuse to move into shooting range. One hunter leaves the blind, but the crows won't appear. The second hunter leaves the blind, but the crows still won't budge. Only when the third hunter leaves, the crows realize that the coast is clear and resume their normal feeding activity.

    Helen Ditz and Professor Andreas Nieder of the University of Tübingen found the neuronal basis of this numerical ability in crows. They trained crows to discriminate groups of dots. During performance, the team recorded the responses of individual neurons in an integrative area of the crow endbrain. This area also receives inputs from the visual system. The neurons ignore the dots' size, shape and arrangement and only extract their number. Each cell's response peaks at its respective preferred number.

    The study published in PNAS provides valuable insights into the biological roots of counting capabilities. "When a crow looks at three dots, grains or hunters, single neurons recognize the groups' 'threeness' ," says Helen Ditz. "This discovery shows that the ability to deal with abstract numerical concepts can be traced back to individual nerve cells in corvids."

    What makes this finding even more interesting is that a long evolutionary history separates us from birds. As a consequence, the brains of crows and humans are designed very differently.

    "Surprisingly, we find the very same representation for numbers as we have previously discovered in the primate cortex," Prof. Andreas Nieder says. "It seems as if corvids and primates with independently und distinctively developed endbrains have found the same solution to process numbers." Even abstract behavior which we think of as sophisticated mental feats ultimately has biological roots.


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

    Journal Reference:
    1. Helen M. Ditz and Andreas Nieder. Neurons selective to the number of visual items in the corvid songbird endbrain. PNAS, June 2015 DOI: 10.1073/pnas.1504245112

     
  3. Allisiam

    Allisiam Well-Known Member

    Messages:
    504
    Are plants intelligent? New book says yes​
    A new book, Brilliant Green, argues that not only are plants intelligent and sentient, but that we should consider their rights, especially in the midst of the Sixth Mass Extinction

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    Beech Tree, on the North Downs near Dorking, Surrey, UK. Photograph: Derek Croucher
    Jeremy Hance
    Tuesday 4 August 2015 04.43 EDT Last modified on Tuesday 4 August 2015 09.29 EDT

    Plants are intelligent. Plants deserve rights. Plants are like the Internet – or more accurately the Internet is like plants. To most of us these statements may sound, at best, insupportable or, at worst, crazy. But a new book, Brilliant Green: the Surprising History and Science of Plant Intelligence, by plant neurobiologist (yes, plant neurobiologist), Stefano Mancuso and journalist, Alessandra Viola, makes a compelling and fascinating case not only for plant sentience and smarts, but also plant rights.

    For centuries Western philosophy and science largely viewed animals as unthinking automatons, simple slaves to instinct. But research in recent decades has shattered that view. We now know that not only are chimpanzees, dolphins and elephants thinking, feeling and personality-driven beings, but many others are as well. Octopi can use tools, whales sing, bees can count, crows demonstrate complex reasoning, paper wasps can recognise faces and fish can differentiate types of music. All these examples have one thing in common: they are animals with brains. But plants don’t have a brain. How can they solve problems, act intelligently or respond to stimuli without a brain?
    "Intelligence is the ability to solve problems and plants are amazingly good in solving their problems."
    Stefano Mancuso
    “Today’s view of intelligence - as the product of brain in the same way that urine is of the kidneys - is a huge oversimplification. A brain without a body produces the same amount of intelligence of the nut that it resembles,” said Mancuso, who as well as co-writing Brilliant Green, is the director of the International Laboratory of Plant Neurobiology in Florence.

    As radical as Mancuso’s ideas may seem, he’s actually in good company. Charles Darwin, who studied plants meticulously for decades, was one of the first scientists to break from the crowd and recognise that plants move and respond to sensation – i.e., are sentient. Moreover, Darwin – who studied plants meticulously for most of his life, observed that the radicle – the root tip – “acts like the brain of one of the lower animals.”

    Plant problem solvers

    Plants face many of the same problems as animals, though they differ significantly in their approach. Plants have to find energy, reproduce and stave off predators. To do these things, Mancuso argues, plants have developed smarts and sentience.
    “Intelligence is the ability to solve problems and plants are amazingly good in solving their problems,” Mancuso noted.
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    Pinguicula casabitoana is the only carnivorous plant native to the Dominican Republic. Found on just one particular ridge on Mount Casabito, this insect-eating plant is one of the rarest carnivorous plants on the planet. Photograph: Tiffany Roufs​
    To solve their energy needs, most plants turn to the sun – in some cases literally. Plants are able to grow through shady areas to locate light and many even turn their leaves during the day to capture the best light.

    Some plants have taken a different route, however, supplying themselves with energy by preying on animals, including everything from insects to mice to even birds. The Venus flytrap may be the most famous of these, but there are at least 600 species of animal-eating flora. In order to do this, these plants have evolved complex lures and rapid reactions to catch, hold and devour animal prey.

    Plants also harness animals in order to reproduce. Many plant use complex trickery or provide snacks and advertisements (colours) to lure in pollinators, communicating either through direct deception or rewards. New research finds that some plants even distinguish between different pollinators and only germinate their pollen for the best.

    Finally, plants have evolved an incredible variety of toxic compounds to ward off predators. When attacked by an insect, many plants release a specific chemical compound. But they don’t just throw out compounds, but often release the precious chemical only in the leaf that’s under attack. Plants are both tricky and thrifty.

    “Each choice a plant makes is based on this type of calculation: what is the smallest quantity of resources that will serve to solve the problem?” Mancuso and Viola write in their book.

    In other words, plants don’t just react to threats or opportunities, but must decide how far to react.
    The bottom of the plant may be the most sophisticated of all though. Scientists have observed that roots do not flounder randomly but search for the best position to take in water, avoid competition and garner chemicals. In some cases, roots will alter course before they hit an obstacle, showing that plants are capable of “seeing” an obstacle through their many senses.

    Stefano Mancuso talks plant intelligence at TED.

    Humans have five basic senses. But scientists have discovered that plants have at least 20 different senses used to monitor complex conditions in their environment. According to Mancuso, they have senses that roughly correspond to our five, but also have additional ones that can do such things as measure humidity, detect gravity and sense electromagnetic fields.

    Plants are also complex communicators. Today, scientists know that plants communicate in a wide variety of ways. The most well known of these is chemical volatiles – why some plants smell so good and others awful – but scientists have also discovered that plants also communicate via electrical signals and even vibrations.

    “Plants are wonderful communicators: they share a lot of information with neighbouring plants or with other organisms such as insects or other animals. The scent of a rose, or something less fascinating as the stench of rotting meat produced by some flowers, is a message for pollinators.”
    Many plants will even warn others of their species when danger is near. If attacked by an insect, a plant will send a chemical signal to their fellows as if to say, “hey, I’m being eaten – so prepare your defences.”


    Researchers have even discovered that plants recognize their close kin, reacting differently to plants from the same parent as those from a different parent.

    “In the last several decades science has been showing that plants are endowed with feeling, weave complex social relations and can communicate with themselves and with animals,” write Mancuso and Viola, who also argue that plants show behaviours similar to sleeping and playing.
    6a4f6da8-c646-4866-8f68-e3ee9c06f14f-1275x2040.
    A new book explores the intelligence and sentience of plants. Photograph: Island Press​
    And it turns out Darwin was likely right all along. Mancuso has found rising evidence that the key to plant intelligence is in the radicle or root apex. Mancuso and colleagues recorded the same signals given off from this part of the plant as those from neurons in the animal brain. One root apex may not be able to do much. But instead of having just one root, most plants have millions of individual roots, each with a single radicle.
    So, instead of a single powerful brain, Mancuso argues that plants have a million tiny computing structures that work together in a complex network, which he compares to the Internet. The strength of this evolutionary choice is that it allows a plant to survive even after losing 90% or more of its biomass.

    “The main driver of evolution in plants was to survive the massive removal of part of the body,” said Mancuso. “Thus, plants are built of a huge number of basic modules that interact as nodes of a network. Without single organs or centralised functions plants may tolerate predation without losing functionality. Internet was born for the same reason and, inevitably, reached the same solution.”

    Having a single brain – just like having a single heart or a pair of lungs – would make plants much easier to kill.
    “This is why plants have no brain: not because they are not intelligent, but because they would be vulnerable,” Mancuso said.
    In this way, he adds, it may be better to think of a single plant as a colony, rather than an individual. Just as the death of one ant doesn’t mean the demise of the colony, so the destruction of one leaf or one root means the plant still carries on.

    The wide gulf

    So, why has plant sentience – or if you don’t buy that yet, plant behaviour – been ignored for so long?
    Mancuso says this is because plants are so drastically different from us. He says it is “impossible” for us to put ourselves in the place of a plant.
    “We are too different; the fruit of two diverse evolutive tracks...plants could be aliens for us,” he said. “But all the same we share with plants life, the same needs, we evolved on the same planet. In the end we respond in the same way to the same impulses.”
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    The banana orchid is threatened with extinction. Photograph: Jose Pestana/PA​
    Plants also largely live on a different timescale than animals, moving and acting so slowly that we hardly notice they are, indeed, reacting to outside stimuli.
    Due to our vast differences, Mancuso says, plants fail to attract interest in the same way as, say, a tiger or an elephant.
    "We depend on plants, thus plant conservation is necessary for man conservation."
    Stefano Mancuso
    “The love for plants is an adult love. It is almost impossible to find a baby interested in plants; they love animals,” he said. “No child thinks that a plant is funny. And for me it was no different: I began to be interested in plants during my doctorate when I realised that they were capable of surprising abilities.”

    This has resulted in very few researchers studying plant behaviour or intelligence, unlike queries into animals.

    “Today the vast majority of the plant scientists are molecular biologists who know [as much] about the behaviour of plants as much as I know of cricket,” said Mancuso.

    Yet, humankind’s disinterest and dispassion about plant behaviour and intelligence may put our very survival at stake.
    Totally dependent on plants

    While plants are by no means as diverse as the world’s animals (no one beats beetles for diversity), they have truly conquered the world. Today, plants make up more than 99 percent of biomass on the planet. Think about that: this means all the world’s animals – including ants, bluewhales, and us – make up less than one percent.

    “We depend on plants, thus plant conservation is necessary for man conservation,” said Mancuso.
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    Deforestation in the Amazon. Forest destruction worldwide has pushed innumerable species into extinction, many of which we may never know. Photograph: luoman/Getty Images/iStockphoto​
    Yet, human actions – including deforestation, habitat destruction, pollution, climate change, etc. – have ushered in a mass extinction crisis. While plants in the past have fared better in previous mass extinctions, there is no guarantee they will this time.

    “Every day a consistent number of plant species that we never met, disappears,” noted Mancuso who added that mass extinctions “are never happy events and I suspect that, despite their diversity, even plants don’t like to disappear.”

    At the same time, we don’t even know for certain how many plant species exist on the planet. Currently, scientists have described around 20,000 species of plant. But there are probably more unknown than known.

    “We have no idea about the number of plant species living on the planet. There are different estimates saying we know from 10 to 50% (no more) of the existing plants,” said Mancuso.
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    Charles Darwin was one of the earliest proponents of plant intelligence. Illustration: Island Press​

    Many of these could be wiped out without ever being described, especially as unexplored rainforests and cloud forest – the most biodiverse communities on the planet – continue to fall in places like Brazil, Indonesia, Malaysia, the Democratic Republic of the Congo and Papua New Guinea, among others.

    Yet, we depend on plants not only for many of our raw materials and our food, but also for the oxygen we breathe and, increasingly it seems, the rain we require. Plants drive many of the biophysical forces that make the Earth habitable for humans – and all animals.

    “Sentient or not sentient, intelligent or not, the life of the planet is green...The life on the Earth is possible just because plants exist,” said Mancuso. “Is not a matter of preserving plants: plants will survive. The conservation implications are for humans: fragile and dependent organisms.”

    Still, there are few big conservation groups working directly on plants – most target the bigger, fluffier and more publicly appealing animals. Much like plant behaviour research, plant conservation has been little-funded and long-ignored.

    Mancuso says the state of plant conservation and the rising evidence that plants are sentient beings should make people consider something really radical: plants’ rights.

    “It is my opinion that a discussion about plants’ rights is no longer deferrable. I know that the first reaction, even of the more open-minded people, will be ‘Jeez! He’s exaggerating now. Plant’s right is nonsense,’ but should we not care? After all the reaction of the Romans’ father to the proposal of rights for women and children, was no different. The road [to] rights is always difficult, but it is necessary. Providing rights to plants is a way to prevent our extinction.”
     
  4. Allisiam

    Allisiam Well-Known Member

    Messages:
    504
    Is Our Universe a Hologram? - Instant Egghead #63


     
  5. raxnae

    raxnae One Love, One Heart

    Messages:
    51
    Scientists May Have Just Figured Out Why Time Moves Forward, Not Backwards

    January 29, 2016 | by Alfredo Carpineti
    shutterstock_122113648.
    photo credit: Time flies like an arrow, fruit flies like a banana. agsandrew/shutterstock
    43.7K

    Griffith University Associate Professor Joan Vaccaro has put forward a suggestion on why there’s a difference between the future and the past. According to her calculations, the laws of physics don’t have to distinguish between time and space, but since we don't experience time in the same way as space, something must make time different. And she thinks the answer is in a special class of quantum phenomena.
    Certain quantum phenomena don’t behave in the same way if you’re going forward or backward in time, and she suggested that these are the key to understanding the arrow of time – the "asymmetry", or one-way direction, of time. And she said that in particular, subatomic particles known as K and B mesons could provide some interesting information. Her research is published in the Proceedings of The Royal Society A.
    “If you want to know where the universe came from and where it’s going, you need to know about time,” Vaccaro said in a statement.
    “Experiments on subatomic particles over the past 50 years show that nature doesn’t treat both directions of time equally. In particular, subatomic particles called K and B mesons behave slightly differently depending on the direction of time.”
    science-reveals-most-addictive-food Here's an analogy: If you leave a cup of coffee on the table you’d expect it to stay there. Sure, maybe you can move it around on the table, but it would still be a cup on a table. If the cup started flickering in and out of existence, you’d think something really weird was going on.
    The flickering of the cup is not something we experience because it would violate theconservation of mass, but if space and time are truly two sides of the same coin, then it should be allowed to happen. And as an object is limited in space (it has got a size and a position), they could also be limited in time (they could appear and disappear).
    “In the connection between time and space, space is easier to understand because it’s simply there," she added. "But time is forever forcing us towards the future.
    “Yet while we are indeed moving forward in time, there is also always some movement backwards, a kind of jiggling effect, and it is this movement I want to measure using these K and B mesons.”
    Professor Vaccaro reworked the equations of quantum mechanics in a way that the conservation of mass wasn’t a given condition of the universe. She thus discovered that time and space did truly behave identically in that scenario. Even more interestingly, once violations of symmetries are allowed, the equations evolved into the ones that describe our universe and the law of conservation of mass arises organically from this theory.
    “Understanding how time evolution comes about in this way opens up a whole new view on the fundamental nature of time itself," she said. "It may even help us to better understand bizarre ideas such as travelling back in time.”
    Image in text: Associate Professor Joan Vaccaro, from Griffith's Centre for Quantum Dynamics. Griffith University




    http://www.iflscience.com/physics/new-explanation-why-time-moves-forward
     
    Last edited: Jan 31, 2016
  6. raxnae

    raxnae One Love, One Heart

    Messages:
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    Germany's Fusion Reactor Creates Hydrogen Plasma In World First

    February 3, 2016 | by Robin Andrews
    Greifswald-device-718x523.
    photo credit: The experimental fusion reactor. Max Planck Institute
    920

    Scientists at the Max Planck Institute in Germany have successfully conducted a revolutionary nuclear fusion experiment. Using their experimental reactor, the Wendelstein 7-X (W7X) stellarator, they have managed to sustain a hydrogen plasma – a key step on the path to creating workable nuclear fusion. The German chancellor Angela Merkel, who herself has a doctorate in physics, switched on the device at 2:35 p.m. GMT (9:35 a.m. EST).
    As a clean, near-limitless source of energy, it’s no understatement to say that controlled nuclear fusion (replicating the process that powers the Sun) would change the world, andseveral nations are striving to make breakthroughs in this field. Germany is undoubtedly the frontrunner in one respect: This is the second time that it’s successfully fired up its experimental fusion reactor.
    Last December, the team managed to suspend a helium plasma for the first time in history, and they’ve now achieved the same feat with hydrogen. Generating a hydrogen plasma is considerably more difficult than producing a helium one, so by producing and sustaining one in today’s experiment, even for just a few milliseconds, these researchers have achieved something truly remarkable.
    As a power source, hydrogen fusion releases far more energy than helium fusion, which is why sustaining a superheated hydrogen plasma represents such a huge step for nuclear fusion research.
    John Jelonnek, a physicist at the Karlsruhe Institute of Technology, led a team that was responsible for installing the powerful heating components of the reactor. “We’re not doing this for us,” he told the Guardian, “but for our children and grandchildren.”


    In order to initiate the fusion process, extremely high temperatures of around 100 million degrees Celsius (180 million degrees Fahrenheit) have to be reached within the reactor. At these temperatures, atoms of hydrogen become energetically excited.
    At a high enough ignition temperature – along with the aid of an effect called “quantum tunneling” – they begin to collide and fuse, releasing energy within a plasma cloud and forming heavier elements. In order for the plasma to be sustained, it must not touch the cold walls of the reactor, so the stellarator’s 425 tonnes (470 tons) of superconducting, super-cooled magnets are used to keep it suspended in one place.
    This 16-meter-long (52 feet) experimental fusion reactor is one of the largest in the world. It took 19 years and €1 billion ($1.1 billion) to complete. This reactor is not designed to produce any usable energy, but rather recreate the conditions found deep within our own Sun – namely, to create a sustained, super-hot plasma, the energy source of a viable fusion reactor.
    By successfully creating and capturing helium plasma last year, the scientists at the Max Planck Institute showed that it was certainly possible. This earlier plasma generation also “cleaned” out the stellarator, removing dirt particles that would have interfered with today’s more important hydrogen plasma-generating test.


    http://www.iflscience.com/physics/germanys-fusion-reactor-creates-hydrogen-plasma-world-first
     
  7. raxnae

    raxnae One Love, One Heart

    Messages:
    51
    Gravitational Waves Have Been Detected For The First Time

    February 11, 2016 | by Alfredo Carpineti
    GravWaves_0.
    photo credit: An exaggerated version of how the two black holes merging might create gravitational waves. IFLScience/C. Jones

    The Laser Interferometer Gravitational-Wave Observatory (LIGO) in the United States has detected gravitational waves for the first time. This is one of the most important astrophysical observations since the discovery of the Cosmic Microwave Background.
    “We have detected gravitational waves. We did it!” said Daivd Reitze, Executive Director of the LIGO Laboratory at the California Institute of Technology, at a press conference announcing the discovery
    Gravitational waves are a prediction of Einstein’s Theory of General Relativity. According to Einstein, gravity bends space-time, and the more massive an object is, the larger the effect. When massive objects move they create an oscillation in space-time, gravitational waves, a bit like the waves that form in front of a moving ship.
    The gravitational waves were observed on September 14, 2015, and they were produced by a pair of merging black holes, one of the few events thought powerful enough to produce gravitational waves that we can detect. The two objects are about 150 kilometers (95 miles) across and merged 1.3 billion years ago. They had similar masses, one weighing 36 times the mass of the Sun and the other 29. The discovery has a statistical significance of 5.1 sigmas, meaning that there’s only 1 chance in almost 6 million that the result is a fluke. The results will be published in the journal Physical Review Letters.
    The power released by the merging black holes was equivalent to 50 times the power of all the stars in the visible universe. In those 20 milliseconds, the energy of the waves was equivalent to annihilating the mass of three Suns.
    It will bring to a head decades of searching by scientists, who have long sought evidence for gravitational waves. They are thought to move through the universe, squeezing and stretching the fabric of space-time, but the oscillations are incredibly small and thus very difficult to detect, requiring incredibly sensitive instrumentation such as LIGO.
    "Detecting and measuring gravitational waves is the holy grail of Einstein’s theory of General Relativity," said Professor Bob Bingham, a physicist at the Science and Technology Facilities Council at Harwell Campus in the U.K. "This discovery leads the way to look back in time at the creation of the universe, with significant repercussions for ongoing astronomical research."
    [​IMG]
    LIGO facility in Livingston, Lousiana. LIGO/NSF
    LIGO is made up of two detectors, one in Hanford, Washington and the other in Livingston, Louisiana. Both detectors have a laser system that allows precise measurements of space-time. At each LIGO facility, a laser beam is split into two and sent down two perpendicular tunnels, each 4 kilometers (2.5 miles) long with a mirror at the end. The lasers are reflected and then combined back together. If a gravitational wave crosses one or both lasers, it will change the distance the light had to travel, and the reconstructed beam will look different from the original.
    The LIGO teams from the two facilities compared notes to confirm if the observation was real or a fluke, and contacted astronomical observatories to follow up the detection with an observation of the possible cause of the gravitational wave, leading to the suspected merging black holes.
    "The long-term goal for the LIGO detectors and its observations is to do astrophysics," Vicky Kalogera, said. "We want to use the gravitational-wave observations to learn about our universe for decades and centuries to come."
    Another important piece of information to have come out of the announcement is that gravitational waves move at the speed of light. This was expected theoretically, but having this proven is important in constructing future theories. And this observation also confirms the first intermediate-mass black holes ever found. Stellar black holes are usually much smaller, reaching at most 15 solar masses. The objects observed are significantly bigger and they are believed to be a remnant of the first stars in the universe. The merger of intermediate mass black holes is thought to eventually produce the supermassive black holes we observe at the center of galaxies.
    Later this year, the VIRGO facility (which is similar to LIGO) will re-open in Italy, and combining the data with LIGO will allow for triangulation of the source to find out the location of the black holes. And the LISA Pathfinder mission is currently investigating technologies that will be used on another gravitational wave experiment, the LISA observatory, which will be constructed in outer space to provide further information on this fascinating phenomenon.
    The detection of gravitational waves is truly momentous, and heralds a completely new era in astronomy.



    http://www.iflscience.com/space/gravitational-waves-observed-first-time
     

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