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tv   What Did the Big Bang Sound  Deutsche Welle  February 7, 2021 9:15am-10:00am CET

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2000 general admission fans lucky enough to have gotten tickets for the super bowl masks of course will be mandatory. well you're watching news live from berlin up next our documentary series doc film we'll have more headlines for you at the top of the hour michael okun brylin we'll see you soon. and you hear me you know my dear sweet girl you and i last year's jam and sunflower with your new angle a magical and you never have surprise yourself with what is possible who is magical really what moves back and what. who talked to people and followed her along the way maurice and critics alike join us the metals lifestyle.
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ever since the early days of humanity we have gazed in or at the starry sky and asked what awaits us out there. technological progress has given us more answers than we could ever have dreamed yet with every step towards understanding and every frontino we cross the universe presents us with new mysteries. is this undergo this as a golden age for astronomy and our exploration of the universe it's never been so exciting and everything we learn tells us there is a lot more we don't know yet that the design ways of looking which are open to virtually all sorts of things you have thought of how do you do that and how do you look for something you don't know. he says a story about for such for the are known and about the people working to solve its mysteries it's safe to say that it's a success story because. well and with us or understanding our universe and its
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wonders a little bit better. and all thanks to a short in conspicuous signal from the depths of space that found its way to earth at just the right moment a signal that made astronomers around the world sit up and listen. it began with a drama of cosmic proportions at a distance of 1300000000 light years 2 black holes was spiraling toward one another each was many times more massive than our sun. finally they collided we have and it was so violent that it released waves of enormous energy gravitational waves these then sped through space over
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a way to us where they were detected in september 25th date. what we would have done is opened a new field of astronomy that's what's so important we're now using gravitational waves and as looking at the universe of a completely new way as ours grounds it was tremendously exciting for the 1st time we've heard the universe not just seen it in a book it was definitely one of the discoveries of the century and. the sensational discovery took place in the east of washington state in the u.s. the desert area is home to one of 2 american gravitational wave detectors called lie go it shaped like the letter l with a kilometer long arms it was these arms and the laser beams inside them but enabled the signal to be detected in 2015. david shoemaker helped build
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lie go the visitors does giving us a rare glimpse inside the heart of what is arguably the world's most sensitive measuring device. work inside one of the beam to cover just where they used for light travels to detect gravitational radiation the thing we're looking at right here is the beam tube itself it's about a metre in diameter and it's made at the famous steel credit thin way about 4 millimeters thick but the idea is to have an extremely good vacuum so when the laser light travels along the 4 kilometers it's not just her by any hair. in technical terms it's called a laser interferometer each of the detectors arms is exactly 4 kilometers long where they meet a laser beam and split and shot down both arms. it functions a bit like a gigantic ruler. passed laser light along the
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trip to measure the distance very precisely between 2 mirrors that are 4 kilometers apart and very precisely i mean 2.0000000000000001 of a meter and if any molecules of air pass through that being and causes a very small shift in the distance what we're doing inside these tubes is removing all of that air so that effect is a completely that logical level for the measurements that when you can make and the only thing that should change the path length between these 2 mirrors is a passive gravitational way. but how can this giant laser ruler on earth become signals from deep in space. the answer lies in the nature of the signal. as the 2 blancos around each other faster and faster and eventually merged the energy waves that were treated. was so enormous that they changed banks around them
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. very similar to what a way what a way this transfers meaning it does its up and down motion of the water perpendicular the direction in which it moves it's very much the same except in this case. stretch of space in one direction in which it moves but and then a contract space in the other and that ball reverses for a while it's extracting space this way contract in space that way a little bit later it's compressing paste this way and stretching space advocates alternating between those 2 things you don't need any more than that to understand what how you detect the waves. nor what they really are. 1.3000000000 years these gravitational waves traveled through space before reaching . year 2 they compressed and stretched space. we could notice the change but the detector could for a brief instant the waves change the length of light goes arms. as
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a gravitational wave passes it squeezes the star and stretches the storm and then squeezes the starman stretches this far what we do is we measure the time for the light to take this path 1st of the time to take this path and we see if there is a difference it could be to program attention away the detector is so sensitive that even the smallest develop quakes is registered as a signal in the line go control room. even south from the far away beach is displayed here both of these to rest real disturbances make isolating a signal that's actually coming from space a huge challenge for the scientists. at the beginning of the existence of these 2 objects they're turning around to each other extreme way slowly billions of years of the 1st person or so but by the time
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they get into a frequency range where our instruments are sensitive and we can get above the frequencies for seismic noise it's completely gone for us and they're already into this range which is close to human hearing so something like look that's the kind of sound that you get if you take this of electrical signal and you put it through an amplifier into a loud speaker the ever required to pick up that tiny is enormous but the payback is what such signals can tell us about because most gravitational waves allow us to explore parts of the universe that no telescope or space probe could ever reach simply teaches about the great on. known. dommage how many shots don't they give us the chance to hear from the dark side of
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the universe is ago and we now know that over 99 percent of the universe is dark and will probably never be detectable with any kind of electromagnetic waves but we also know that everything is subject to gravity and any object subject to gravity that moves makes gravitational waves or where. merging black holes colliding neutron stars stars that explode into supernovas more violent events and the more massive the objects involved the stronger the gravitational waves they generate. black holes are so massive that they devour everything that approaches to collapse so when 2 of them come light a gigantic amount of energy is released gravitational waves carry information about such cosmic events out into space and once they're on their way nothing in the universe can stop them. it doesn't matter whether there's dust there or it doesn't
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matter if there's radiating plasma there we look right through it that's what that means we can look through everything we may even look at the very moment that the universe god created that may happen not now probably 30 years from now we will be able to do experiments that that look at the gravitational radiation that came from the instant. that the universe god formed in the big bang. there is no greater cosmic event than the birth of the universe itself gravitational waves could be the key to finally understanding the big bang. no wonder that scientists have dreamed for decades about one day being able to measure these way. the drama of the whole thing really starts in 1915 with all albert albert einstein who had come up with this new theory of
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gravity which was now has a name called general relativity. albert einstein is probably the most famous physicist in history with his research he revolutionized the concept of universal physical laws one of einstein's greatest contributions was a completely new way of viewing gravity. now is this track of kind of tough according to einstein gravity isn't a force it's a property of space it arises from the fact that everything makes little dents in space everything else that moves through this curved space and through these depressions take the moon for example or the moon is always moving around the earth in a sort of groove you can't imagine it in 4 dimensions but take something a lastic like a rubber sheet the last issue of all what the earth on it and it makes a depression the moon is always rolling around like a roulette ball in this depression is a. ringback ringback greater an object's mass the bigger the dent it makes in space
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in other words the bigger its gravitational field according to einstein if these objects are accelerating to high speeds it should create waves of curvatures in the fabric of space. the faces there's predicted the existence of gravitational waves more than 100 years ago. but einstein never quite trusted the theory that it's clear he changed his mind at least 5 times throughout his life over whether gravitational waves existed at all pete why because he did what a good scientist does after he made the theory he sat down and put numbers the he put in for the masses he knew and how many there were and what happened he found out that it would be such a tiny little infinitesimal effect at the gravitational waves make that it will never play a role in physics. a computer model shows just how small the in fact is take an
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atom one of the world's tiny building blocks. then zoom in to observe a proton in its nucleus an even smaller unit. only on that scale and you see the spatial bending coast by a passing gravitational. matter you simply didn't have the means to detect something like that 100 years ago when i predicted gravitational waves as the technology only came half a century later and even then it took another half century and till we could actually measure such small changes and now it's almost routine 1st latina. it's precisely this technology that is being researched by the marks planck society at the albert einstein institute in hanover its director cast and dance man is one
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of the leading gravitational wave researchers in germany. together with an international team of scientists he developed a laser system that's at the heart of the u.s. like go detectors it was key to the successful gravitational wave measurement in 2015. the lasers were tested in the countryside a few kilometers outside hanover. places the geo $600.00 germany's only gravitational wave detector. with an arm length of 600 metres it's much smaller than its american counterparts but it's still constant dance man's pride and joy back in the 1990 s. he campaigns for the construction of the laser interferometer here today geo 600 is one of the most important testing stations in this research field. the the interferometers with arms is several kilometers long just sit there and listen you
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can't think or with them or at least it's done as little as possible but if you want to develop things you have to constantly tweak the instruments installment of video that's why you need something like this and then if it all works convincingly that the technology is transferred and incorporated into the big data detectors. there's a unique atmosphere here at the site. from the outside the detector appears plain and in conspicuous like an ordinary installation there's little hint of the impressive things it's capable of the stand here show you stand here looking across the fields is the sun is shining it's very peaceful but then you imagine how out in the universe 2 black holes have collided with each other and then a 1000000000 years later the signal arrives here you don't notice anything but the space under your feet trembles and are instruments buried in the ground registers
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in order that's a great feeling. for 100 years they were down for this moment whatever come. in for nearly the 1st half of that time it was believed to be technically impossible. that began to change in the late 1950 s. . what happened is that people began to look at the einstein theory all over again and they went to this statement that einstein had said look this is impossible to measure and they realize now maybe it's not the technology had changed. one of the then new technologies now looks like a prop from an old science fiction film. but this is actually the world's 1st attempt to building
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a gravitational wave detector. operators was invented by physicist joseph weber at the university of maryland. who was a very. joseph weber was both a pioneer and in the end maybe quite a tragic figure he certainly led the way in experimental gravitational wave research anywhere in the world. and the idea that he had was to. you look at what a gravitational well does to a great big piece of metal like a huge bar huge piece of metal and what it does to that metal and the gravitational wave comes along it stretches it a little bit and then it's gone again but at the blog continues to vibrate just like a bell keeps resenting after it's been struck or that migration was what he wanted was attacked on. in theory it was a brilliant idea but in practice it proved to be a major challenge for webb and his team for the cylinder to be sensitive enough to
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detect gravitational waves it's atoms had to be frozen into a state of almost complete rest so the team built the device in a vacuum chamber and cooled it down. in the 1960 s. several such gravitational wave antennas later known as web os were built according to this principle. weapon you need several independent measurements to prove that his experiment worked as planned. and then came to america. what you think and the scene was something that was were actually world shaking absolutely world shaking and by 969 he published a paper saying that he had discovered gravitational waves. that's a fact the guns are making it was met with a lot of skepticism theoreticians soon realized that
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a signals were actually far too strong if the sources were so intense that he could detect them with his weber bar than most of our milky way would have been destroyed by gravitational waves long ago with that kind of energy. it only took a glance at the night sky to know everything was still hunky dorey with a milky way but weber's work had an impact as far as go for it also wasn't immediately clear that he was wrong if you know i'm going nuts but people began to wonder how strong such gravitational waves could actually be because at the time it was all unknown so researchers began to duplicate these experiments to try to verify that it's obviously if it's. news of weapons supposed success also reached the max planck society in germany at the institute for astrophysics outside munich they did. cited to reproduce the cylinder experiment and they had just the right person for the job experimental physicist heinz building the only thing was he
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didn't really have much experience with astrophysics. building help making computers and do innovations with computers that allowed the people and the astrophysics sensitive there to be able to make large scale computations in astrophysics and spelling was a pioneer at a time when computers still took up entire rooms is achievements in the field of electronics were groundbreaking. and he was known as a rigorous experimenter. belling was born in the town of sounds very little in northern germany he was a year old when and stein published his general theory of relativity. even as a boy billing was fascinated by einstein's ideas at school he was nicknamed meister because of his math skills he seems to have been born with
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a talent for invention and innovation. the electronic sax but enthusiastically took on a proposal to repeat weber's experiment the chance of proving einstein's theory was incentive enough one of the people he recruited for his team was a young physicist from atlanta. just being you that's me over here faltered engler now in his seventy's learned about the planned experiment in an unusual way. this one in our news in that so there was an announcement in the newspaper i've already started a doctorate and alexander funk like came home and my wife said look if they're looking for someone to help measure gravitational waves i saw the article and
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immediately i was electrified her father lived. in a band and his doctoral thesis deciding instead to pioneer research into gravitational waves with hines filling. in the shadows the 2 scientists began to build their own resonant santana based on the web on design. but they were very much much better than whether they were super technicians. and fact that's the key thing to the building group they were solid engineering physicists and they didn't cut corners they knew exactly what they were doing. we were really meticulous in carrying out the weber experiment we improved the amplifiers and other things and feeling over saw it all he was reliable and
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everything he did was done right that's how we went through with it it's whom. despite their different personalities billing and web had a friendly relationship. the american physicist even willingly shared his research with the germans. was not the most thorough experiment he was a very imaginative man and certainly one of the people who originated the field and should get a lot of credit for that but as far as being a super. experimental scientist he was not as good as these people. together with an italian institute and building built to separate resonant time time and improve the instruments as best they could then they began their measurements for 3 years they used the cylinders to listen to space they hoped to pick up the longed for gravitational waves and confirm the unbelievable but the
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result was sobering. they saw nothing they could answer with absolute certainty that they saw nothing it wasn't ambiguous they said the chance of us seeing something or this thing being a gravitational wave is one in a 1000000000 we have on the we were the only ones in the world to do this sort of experiment with clearly better measurements than webber's and we found nothing we thank you for so we came up with the best proof that weber's process did not exist exist yet. joseph weber had been mistaken it was a realisation he was never able to cope with. the search for the unknown which had begun with such high hopes now appeared to have failed.
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the purity of other theoreticians were satisfied their world view was safe and sound once again but it's a bit depressing for the experimenters when it's what you have built up something worked hard and probably for nothing what they pulled off keep in hand the director of the institute at the time said billing to the best job of not proving gravitational waves but the question was what to do next. what i didn't know in munich was that across the atlantic. a completely new idea was gaining momentum. cambridge massachusetts now boston is home to the elite massachusetts institute of technology and mighty. and here in the early 1970 is a new hope was germinating in the field of gravitational wave research it was
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thanks to the simple force experiments of a young professor named rhino weiss the students asked me about the weber experiments i didn't understand the weber experiments so i cooked up a technique where you could do the following to free floating masses in space what you do is you take a light start from one of these masses put a clock on this one and when it sends a light beam to this one you put a clock and stop the clock here then you send a like being back again and look at the clock over here and you look at the time it takes for the light to go from here to there and back again and you write it down and then a gravitational wave comes along and makes a slight difference in the length and you do the same experiment over and you'll find out the different time to tell us the invention of a detector ok big deal. captivated by the idea why steve signed it to spend his summer doing the calculations to see
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if his thought experiment to be turned into a real one. and so my amazement about time i got done. it looked to me like yeah if you made it big enough and you made it with 2 legs so you had one pair one pair of masses this way another pair of basses that way so one l. you could compare one where it's shrinking on the side expanding on the outside you could compare. the south leg with the east west leg and you could actually do the experiment and you need only one thing you need it you need to make it long big. there was just one big problem weiss didn't have the money for sanction experiments at the time he was doing research for the american military but with the us fighting the vietnam war i had no interest in an exotic search for gravitational
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waves eventually he managed to submit his idea to a civil organization the national science foundation. he had no idea that the solution to his problem would come from a well known figure in munich. what happened was the people at the national science foundation sent my proposal to billing he saw it and it looked attractive to him he thought it was a good idea that tells me that you know he was thinking straight. and so he does what any really rational person would do we calls me up and he said that sounds like an interesting idea you're proposing would you mind if we worked on that i said no how could i mine as a scientific member of the max planck society spending was free to pursue whatever research he chimes in 975 together with the fountain of england and a handful of new colleagues he sent to work once again the team designed the 1st
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laser interferometer the forerunner of the light go to taxpayers and a cornerstone of modern gravitational wave research but at the time laser technology was still in its infancy in tiny aren't we had no idea about lasers it was all completely new territory to me when we started with a small interferometer with dimensions of around 10 centimeters that was the 1st interferometer we looked at what signals were there and then we made a 3 metre long while and then a 30 meter long why the federal meter. we cut out all the problems that came along and. we figured out the things we had to watch for in order to measure it as sensitively as was theoretically possible from principi of nutritious. for years and his colleagues tinkered with prototypes that were considerably more complex than webber's element cylinder. they made constant
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improvements to the laser vacuum and mirror systems. billings project grew and with it the hope that they might after all confirm einstein's hypothesis of the existence of gravitational waves. they discovered not only that the idea was good but also discovered a lot of things that i hadn't thought about i've not thought of. problems that i had not thought of in my description of how this might work and they made significant. creative advances in the whole idea of doing this. the laser interferometer would be hines billings final research project he retired in 1982 at the age of 68 but he vowed he would live to see the discovery of gravitational waves.
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his successor was constant dance man who already had plans not only to share the valuable research with his american colleagues but to build his own launch detector . but history had other plans. for the annoyance to go yeah in the early 990 s. i had say our proposals were at about the same stage as the american like o. proposals for large interferometers for. but in the us it happened very quickly like i was approved as a line item in the congressional budget. in germany something happened that we all wanted to happen namely reunification but in the aftermath of reunification there was no money for a while but what there was went to the east for us and it was. in the early 1990 s. 2 decades after the technology was invented the u.s. began constructing to launch interferometers one was built here in 100 washington
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the other in far off louisiana line go technology to relies on at least 2 independent measuring stations it would take another 20 years to find both detectors. in the sites main hall david shoemaker shows us how the advances made over 40 plus years of work finally came together to bring success. the basic idea as we said is that gravitational waves stretch and squeeze space and those 2 arms that we use to measure those lengths are down in this direction for kilometers and down in that direction for kilometers the 2 come together at what we call the vertex where the v.m. splitter is that splits that laser light into 2 equal passes to go down the 24
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kilometer long arms that laser is in a very very clean room it's then threaded into the vacuum system matched with mirrors that are this large into the beam size which is correct to then go down the 4 kilometer length not spreading any more than to about 10 centimeters in diameter that's the basic notion of the system everything that remains is a matter of keeping noise away. and soon they will well prepared when on september the 14th 2015 and tiny sigma reached after a long journey it was the echo of a cataclysmic cosmic event. the
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timing could have been better of course because in the us most everyone was still in bad. as well that's why it was around 2 am and 5 am in the us here it was just before noon so our people were all the way on one of the researchers marco drago was sitting at his computer and watching but. then it went be people. the people. b. is an alert and whenever the detector is recorded data several computer programs run alongside them if the same unusual thing happens and both detectors at the same time sequence like within 10 milliseconds there is an alert. and suddenly there it was a clear signal drago couldn't make sense of it at 1st so he consulted a colleague together they puzzled over the source of the signal that had been
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picked up and the you asked. them is the moment the 1st everyone who saw it thought it was a test signal then that wouldn't have been unusual test signals are constantly fed into the data stream when the detectors are recording but normally there'd be an entry in the database saying test signal and scientists it was confusing so finally they called the us control room and asked if it was a test signal and they said test everyone here is asleep. but not from a longer the excitement grew steadily into my go control center the american soul so i began to wonder what the instruments had recorded normal activities were temporarily suspended i was in maine and i looked at the screen on the 14th of the look and i see
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a very interesting thing it says at least it says fix it they has been cancelled we always fix things on tuesdays i see the same message at hanford fix a day has been cancelled why why has fixed that they've been cancelled all of a sudden there was a message from david shoemaker to me look this planet for a secret location on the web and you'll see something and there was this way for. but it was still far too early to celebrate possible errors still had to be considered everything from simple noise to a hacking attack nothing was ruled out the search had gone on too long to risk it with a premise your announcement. and. we were very very scared of reproducing the weber deal. that was the thing on all of our minds that we could ruin the whole field by making a false claim and this is after having spent now close to $1000000000.00 there
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couple different faces to it right there is there is the intellectual acknowledgement that it must have been a real signal and then there's the change in world view from all of the decades that you spent trying to make an instrument that could possibly do something to the time after when that 1st signal was was observed so i think i was intellectually content that we'd actually detected something after a few weeks and it was months and months and months after that i would still wake up in the morning and ask myself if that really happened. then after a full month spent checking for signals. ladies and gentlemen. we have to check to gravitational waves we did it. only once there was no longer any doubt to the researches allow themselves a discreet sense of triumph.
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puts in the file you when you've been searching for something for dozens of years and then it suddenly there there's no moment when you shout eureka i've found it but there is an awareness that something very special has just happened. creeps up very slowly it takes weeks. in december 27th teen on my go project founders were awarded the greatest on a in science. first and foremost among them was professor rayner weiss after more than 40 years of research he received the nobel prize in physics. none of it would have been possible without. the work of the researchers in munich and hines billing was able to keep his vow he was 102 when he heard the news the
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gravitational waves had finally been detected. as far and in closer for he said he knew that was a great sense of achievement with all the work wasn't in vain to know for sure and if you had actually led to research that's now expanding and growing through that and because it was a relief that all our work had a purpose after all and seeing how the differences are. there are now 5 launch detectors around the world more than a 1000 scientists are cooperating every day recording more and more gravitational waves and that's just the beginning. the latest project takes laser interferometers a step further out into space. the plan is to launch 3 satellites in
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2030 for each equipped with a laser. the ever satellites will form a giant triangular consternation measuring 2 and a half 1000000 kilometers on each side. of. the triangle named lisa shortfall laissez interferometer space antenna will all be. thanks to its immense size it will be an even better detector of gravitational waves. but once we build a laser interferometers in space we can use them to detect the most. as an aging objects in the universe namely the super massive black holes that are at the center of large galaxies and if we can do that then we can eventually listen so far out
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that will reach the end of the universe and that is that will be the big bang or if we can listen far enough out that the signals have been travelling for 13800000000 years then we'll have detected the entire universe effect yet. only gravitational waves can tell us what the big bang was really like they can bring us closer than ever before to answering one of humanity's greatest mysteries . it will take time before we will really solve it but already the 1st detected gravitational waves have directly proven the existence of black holes for the 1st time and soldiers about colliding neutron stars and on a cosmic events. that's not a bad start for such a young field. when
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we 1st started looking at the sky as human beings we saw galaxies and everything looked pretty stationary but when you start looking at an x. rays or you start looking at it and radio waves you find out there's a madhouse out there collisions going on things are sex floating this plasma flying all over the place things are radiating and oscillating and it would be absolutely a miracle. if when we open up now this gravitational wave way of looking at the universe there are things we have never even thought about. and i'm only 63 and with the best of health i might live to 120 that's another 57 years i'm only halfway there as the 15 and everything that's happened in the last 63 years is incredible as the go it will go online. this year so i'll get to hear the big bang. somewhere out there that signal is already on its way.
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the only question is when it will reach us. what's going on here. a house of your very own from a printer. computer games that are healing. my dog needs electricity. shift experience delivers facts and shows what the future holds . good living in the digital world shift. in 15 minutes on d w. the 77 percent. some are calling
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this is news live from berlin germany is hit by treacherous weather as winter begins to bite emergency crews are deployed as extreme weather causes disruption to traffic in several parts of the country snowstorms plaque ice and plummeting temperatures are forecast to continue well into monday also coming up protesters.


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