Lawrence Krauss about Gravitational waves

so my real when I got asked to come I said I would answer questions and they said I should give a talk so I'll give a little talk about about one of the most exciting developments in in in physics recently but my goal will be to just get you maybe confuse you so that you can ask questions and then and so we can spend as long as you want asking questions and if you don't have any questions I'll just go for a coffee okay good so what I want to talk about is the universe and we'll see if the universe will cooperate there we go this is the universe this is a Hubble Space Telescope picture of galaxies and for the young people I was just talking this morning but it's it may be hard for you to appreciate how much our picture of the universe has changed in the last hundred years but I said it this morning I'll say it again because I'm very happy my mother is 97 years old and she just told me before I left I arrived yesterday that her mother who I thought lived in Paul was born in Poland was actually born in the Ukraine so I feel like I'm coming home which is very nice but she was born in 1921 but in 1925 the whole universe consisted of our galaxy one galaxy the Milky Way that was it for science and now we now know when we look out that in the universe that we see there are more than 100 billion galaxies each containing 100 billion stars and here's just a small slice of the sky and you could see if you look at the blue galaxies and the very faint blue galaxies or maybe ten billion light away that means the light from these galaxies took 10 billion years to get here so we could take the picture but our Sun is only four and a half billion years old so that means the light left from these galaxies before our Sun and Earth even existed and if you think about it there may be civilizations that existed on those galaxies ten billion years ago that are now long gone because in five billion years our Sun will burn out and will be long gone and forgotten and if someone if if someone in a galaxy here five billion years from now ten billion years from now some civilization takes a picture of our galaxy as it looks now by the time the pictures taken will be long forgotten and everything that we've done is long forgotten so enjoy it while you can okay but that's just wanted to point this out because every picture of the universe if you look at it long enough and deeply enough should inspire you to think and wonder and all the real world is amazing and since I've been a scientist when I was your age we never had pictures like this we only imagined what the universe looked like and it's been amazing to me in my career to see things that we only dreamed of when I was a student we realized now and you're lucky and living in an interesting time that in I hope for many of you that the changes that take place in the next 40 years will be as dramatic as have taken place in the 40 years that I've been doing science and one of the things that has been imagined and was first imagined by Albert Einstein in 1916 was the possibility of gravitational waves Albert Einstein showed that gravity is a property of space and time that what we experience as gravitational force is really the curvature of space and every mass like me curves space around it but that means when I do this I'm producing a disturbance in space I'm moving my arms and I'm producing a disturbance in space and just like dropping a pebble on a pond produces a wave on the surface of the water when I do this I produce a disturbance in space that propagates outwards and Einstein first realized that in 1916 or so in fact 20 years later he actually thought he made a mistake and that gravitational waves didn't exist Einstein made mistakes you should feel good we all make mistakes hopefully we learned from them but it was long realized that gravitational waves are so weak that we would never thought we'd be able to detect them because gravity is the weakest force in nature so even though I make a ripple in space that moves out when I do this it's so small that you'd never be able to measure the gravitational waves that are produced by my arms to produce very strong gravitational waves you need big masses bigger than me bigger than the earth you need cataclysmic events but what happens but at the same time there are gravitational waves going right through this room all the time as we said sit here and what happens when the gravitational wave comes by this room well let's imagine a gravitational wave is coming out of the board what happens is space gets smaller in that direction and bigger in that direction then smaller in that direction and bigger in that direction space itself changes so in this room right now the distance between those walls is getting smaller and bigger and smaller and bigger and smaller and bigger because of the gravitational waves that are going through this room but the effect is so small that most of you don't detect it unless you were drinking too much last night and maybe then you do but but no but maybe you're all too young to drink I don't know but now but in any case it's happening but the effect is so small that certainly when I was a student we thought it would never be detectable this is the wave going in and out if you want to see the whole wave it looks like that but it's pretty to look at but there's not much information there so the question is can we detect gravitational waves and I'm a theoretical physicist so that means I just write on pieces of paper and I talk and I think but I don't do anything but experimental physicists do do things and I mean all of my experimental colleagues because they take the ideas that we have and try and test them if gravitational waves exist this is science not religion you have to be able to measure them if you can't measure something from the point of view of science it doesn't matter only if you can measure it is it science only if you can measure it in principle so some brave colleagues 50 years ago thought maybe we could measure gravitational waves not from my arms moving around but from the most violent events that happen in our galaxy and other galaxies what would that be well maybe there are a hundred billion stars in our galaxy maybe two stars collide and that's that's a dramatic event well two stars colliding is pretty dramatic but first of all most stars don't collide very often but stars are even two stars like our Sun colliding probably would not produce gravitational waves which are strong enough to detect but maybe maybe there are huge black holes stars that have collapsed and are so dense that amass the size of our Sun would collapse down to the size of Kiev be so dense that one teaspoon full of material would weigh billions of tons if those objects exist in our galaxy or other galaxies and they collided maybe we could attack gravitational waves so over a period of 25 or 30 years people built detectors and this is the first large gravitational wave detector it's in the United States in Hanford Washington there's an identical one in Louisiana one is in the north and one is in the south of the United States there are two of them for reasons I'll describe they're identical and what they are are two tunnels at right angles each three kilometers long and in principle if a gravitational wave came down from above what would happen this tunnel would get a little bit smaller and that tunnel would get a little bit bigger and then this tunnel would get a bit longer and that one will get a little bit shorter so in principle it's really simple all you have to do is measure the length of this tunnel on the measure of the length of that tunnel and watch a change easy not so easy because you can calculate the effect of a gravitational wave from two black holes colliding in our galaxy or nearby galaxies how big would the effect be and this is why I'm a theorist and not an experimentalist because it turns out you'd have to measure the length of this tunnel which is three kilometers long you'd have to measure a change in the length as a gravitational wave came by that length would change by an amount equal to one one thousandth the size of a proton one one thousandth of size of a proton who could do that we can not me but amazingly this detector was built to be able to do that first it didn't it it only got to 1/100 the size of a proton and it was turned on for ten years and no one saw anything but then it was improved and in 2015 I think it was turned on and it and it had the necessary resolution if these black holes were colliding this should detect it now there's an important lesson here because a man named Ray Weiss who I used to know when I did my PhD at MIT it's a university in the United States then Ray was a professor there and he designed this detector the first detector and and when you turn on a very complicated machine you want to tune it up make sure it's working so he told his students ok we'll just do it we'll turn it on and we'll see if it's working don't take data just want to get it working and the students did something very important which all students should work do don't listen to your professors yeah that's applied ok they took the data and one hour after it turned on they saw the signal of gravitational wave signal from two black holes colliding in a galaxy 1.3 billion light-years away now think of that the signal turned out to last two tenths of a second which is the amount of time it took for these black holes to collide I'll show it to you in a moment so two-tenths of a second that signal have been traveling for 1.3 billion years if they turned on the detector two hours later they wouldn't have seen it it's amazingly lucky and as I said this morning to a different group accidents are incredibly important in science and the fact that that was there and it just happened to turn on at the right time was amazingly fortunate now how can you measure a difference in length at that small while you use physics of course and here is what you use lasers and you measure basically a distance by measuring the time it takes a light beam to go from one end of the tunnel and bounce off a mirror at the other end of the tunnel and what what we take is a is a laser beam and split it and then have it come back and as the two ends the tunnel changed it you you eventually as you'll see on here you'll see a a wave but if one of these waves travels a little bit farther than the other waves will interfere with each other and if you design it exactly right so these two waves will negatively interfere you'll have nothing you'll have a dark spot on the screen because the peak of one wave will interfere with the trough of another but if the length changes a little bit then the interference pattern will change and you'll see here in a second you'll see what wasn't a dark spot turned into a light spot and and be using this technique of interferometry you can never measure very small time differences and very small length differences now it's much more complicated than that you actually have to run it back many times you have to use an incredibly powerful laser and you have to get rid of lots of backgrounds because we're measuring time distances that are very small so if a truck hits a pothole 20 miles away from that that machine it will produce a bigger effect than this that's why there are two of them because there's lots of noise in each of these detectors but we have one detector in Washington and one detector in Louisiana and gravitational waves travel at the speed of light so you can calculate that it would take about eight milliseconds eight one thousandth of a second for a gravitational wave to get from one detector to the other if it's traveling in the right way so all you have to do is look at those two detectors and there's lots of noise but you look for a signal that's identical in the two detectors separated by eight one thousandth of a second and that gets rid of a lot of the noise that's the first thing so only in 2015 do we have the technology and by the way mirrors are vibrating due to quantum mechanical effects by a much bigger effect than we're looking for so you have to use very complicated new kinds of atomic physics called quantum optics to play with the laws of quantum mechanics so the motion of the mirror in this direction is reduced and it and it and and it uses the the highest-level technology we now have ten years ago it would have been impossible that's for the experiment but for the theory we have to calculate what we think a gravitational wave what effect the gravitational wave would do that's also very complicated because two colliding black holes the mathematics of calculating the gravitation waves is very complicated only when we had large supercomputers could we predict a signal so only in 2015 did we have the theoretical machinery and the experiments of machinery they all came together and an hour after the signal after the detector turned on here was a signal this is you see half a second this is a signal in Washington this was a signal in Louisiana separated by eight one thousandth of a second when you put the two on top of one another that identical and the the noisy curve is the data the other curve is what you'd predict for two black holes colliding and you see the prediction and the observation agree almost exactly this is a gold-plated event you could never ask for an event this beautiful and it happened right away it's amazing gravitational waves exist we see them and you may say big deal but the fact that we see them tells us something amazing about the universe let me show you a movie this is just an artist's rendering of what it would look like of the two black holes if we could see it here are two black holes we can from the comparing the signal to the prediction it turns out we know that one black hole had a mass of 36 times the mass of the Sun and another black hole had a mass of 29 times the mass of a Sun and the amazing thing is so we've got two objects that are almost 30 times the mass of the Sun and just before they collide they were orbiting around each other 200 times per second it takes us a year to go around the Sun these two objects are moving around each other almost at the speed of light 200 times a second they're going around and they produce a signal that has a frequency of 200 and then 300 and then 400 in the audio range you'd actually hear the signal and if I had a microphone there this this will actually also play the signal you can actually hear it it's in the audio region but what you see here is space looks a little weird that's because the black holes are so massive that if we looked at them if we could actually see them which we can't the space would Bend around them and heels and when I make the movie go you'll see that the stars move that's because the light is bending around the black holes as it moves so watch this had slowed down it the whole process takes two-tenths of a second but you'll see what happens and at the very end you'll see space jiggle and that's the gravitational waves so let's watch it so you just this is just the image of gravitational lensing as space is bending around the black holes if if we could see it and this is very slowed down these are actually moving around each other 200 times a second or so but in the last moment watch space there's beginning to jiggle at a frequency there was that was the signal and it lasted two-tenths of a second and it caused space on earth to jiggle a very little bit but we could measure it this is a triumph of the human intellect that we could first know that Einstein could predict the gravitational waves exist that we could build a detector that could do this that people would have the courage the intellectual courage to spend 30 years of their life building a detector that may see a signal that doesn't exist because we didn't know if there were black holes like this in our we thought there might be but we didn't know it's one of the greatest triumphs in my mind of the human imagination and we should celebrate that we're alive during this time now maybe the fact that we can detect this doesn't impress you I hope it does but if it doesn't this should impress you nature is stranger than we can imagine in a sense and I told you that there was one black hole of mass 36 times the mass of the Sun and one black hole of mass 29 times the mass of Sun they combined together to form a black hole 36:29 how massive is the black hole that they form your students 36:29 36 and 29 come together to form a black hole what's the mass of the black hole who said 65 who's hit 65 no one said 65 wrong they form a black hole of mass 62 times the mass of the Sun where did the other three solar masses go into gravitational waves mass got turned into energy now that might not impress you but our Sun will last 10 billion years burning hydrogen fuel with maybe a billion hydrogen bombs going off every second turning mass into energy over the lifetime of our Sun less than about one one thousandth of the mass of the Sun over ten billion years will turn from mass to energy so for ten billion years our Sun will burn powering our civilization and everything on earth for ten billion years and one one thousandth the mass of the Sun will be turned into energy when these two black holes collided in two-tenths of a second three times the mass of our Sun got turned from matter to energy meaning that more energy was released in that collision in that 2/10 of a second than is released in all the rest of the stars in the visible universe and we would never have known about it if we didn't have that gravitational wave detector now that is amazing okay you don't look enough amazed so I'm going to show you something else now since then we've detected more gravitational waves not just from colliding black holes but there are other objects that are very dense when stars collapse if they're very massive after their nuclear nuclear fuel burns they collapse and if they're very massive they collapse into a black hole but if they're not that massive what happens in a period of about one second the nuclear fuel finishes burning the core of the star which starts out to be about the size of the mass of the earth collapses to the form to the size of Kiev in one second and then it becomes so dense basically becomes one giant atomic nucleus of mass number 10 to the 56 at that point nuclear forces take over and it can't collapse any more so the star collapses the inside suddenly it can't collapse there's a shock wave that goes out and blows out the outer part of the star into what we call a supernova all the elements that make up your body were produced in stars because the only elements that were produced in the Big Bang were hydrogen helium and a little bit of lithium but carbon nitrogen oxygen iron all of that was produced in the core of stars and the only way could get into your bodies was if the stars were kind enough to explode which they did over the last 13 billion years so that material all you are Stardust you are made of stars but there was a there was a problem everything up to iron is produced in stars what about the elements heavier than iron gold platinum all the way up led what about that well they're not produced in the cores of stars where were they produced well that wasn't an open question when I was your age lots of debate well there was an idea and it was a really exotic idea maybe if you have a star collapse and a supernova what's left over after the outer part blows out you have an incredibly dense giant atomic nucleus it's so dense that it turns out the protons turn into neutrons and you have what's called a neutron star the density of neutron star is about a hundred billion tons in a little teaspoon full of material and we know there are neutron stars in our galaxy we can we can measure them one could calculate that every now and then two stars many stars are in binary pairs and it is still amazing to me that when one star explodes it doesn't blow the other star away sometimes and you could have two neutron stars orbiting each other when those two neutron stars collide they're very dense you produce gravitational waves but unlike black holes which are just holes in space there's nothing that comes out if two neutron stars collide gravitational waves come out but so does a lot of other stuff gamma rays and x-rays ultraviolet radiation visible light radio waves all of that comes out from that incredibly dense collision so what's amazing is last year the gravitational wave detector LIGO and another Virgo detected a gravitational wave event that had the signature of two neutron stars colliding and they sent out an alert to the whole astronomical community and all the telescopes on earth gamma-ray telescopes x-ray telescopes ultraviolet telescopes visible light telescopes radio waves detectors all looked in that direction to see if they could see the event to see if our predictions of what would happen when a gravitational wave winner when two neutron stars collided if those predictions were correct and here's what we saw this by the way is a neutron star so this is this is not a real one but if this is New York City here and you can imagine this is what a neutron star to look like it'd be the mass of a Sun about the size of New York and this is a simulation of the event that was detected about a year ago of two neutron stars colliding now stuff is coming out because these aren't black holes there's material here and as they collide and if I have the sound you'd hear a little twerp now gamma rays and rate a relative a suggest sermon and x-rays as radioactive materials come out and decay then they turn into all different radiation then the material hits the interstellar medium and produces excitations as visible light all of those things were predicted they were all seen and this solved a problem that had been around since I was a student how many of you have something gold right now maybe a gold ring or a gold necklace that anyone some people good okay don't your heads and simply up your hand it's okay so our civilization has been profoundly affected by the desire for gold it's changed lives people get killed people try and win it people destroyed civilizations in the desire to get gold so human culture has been dramatically changed by the presence of gold since antiquity and I find it credibly interesting because where does the gold come from it turns out the ideas we thought we had 30 years ago was that the place that gold is formed is when two neutron stars collide because the heavy elements have many more neutrons than they have protons and where can you get all those neutrons when two neutron stars collide there's all this energy and maybe you can build up the elements after iron then the idea was a process called the art process and other processes that might produce gold well we were able to observe with the MIT with the telescopes that we pointed towards the objects that produce these gravitational waves the x-rays that came from radioactive materials that would be produced in the collision of those nuclear neutron stars that would produce gold and we saw that in the course of a few days more than one earth mass of gold was created so when you now look down at your gold ring that's where it had to come from one of the most exotic things in the world when you're holding gold you're holding the results of the collision of two neutron stars the densest objects in the universe other than black holes and we now know that's the case because we could measure gravity waves from two colliding neutron stars so maybe gold is valuable at least from a cosmic sense we are not just star children but we are the children of the most exotic wild events in the universe because neutron stars don't collide very often very rarely but the universe is big and old and that means rare events are happening all the time stars explode once every hundred years per galaxy but there are so many galaxies out there that every second a star is exploding somewhere in the universe so we can use that if we look out at the universe and try and detect strange things now now that's where gravitational waves are now but I want to spend the next few minutes talking about where gravitational waves will be because I want to talk about something that's of interest to me which is another source of gravitational waves well the other way this is the Milky Way seen at night in a beautiful spot and somewhere out there where neutron stars that collided and produced material that ended up being in our region of the solar system when our Sun began to collapse and then and the solar system began to collapse around it it's remarkable that that happens still amazes me ok there is another way to look for gravitational waves from a very different source this is the South Pole this is a detector that looks at radio waves not radio waves from stars but radio waves from the Big Bang microwaves actually it turns out that there's radiation called the cosmic microwave background radiation that was that is a remnant of a time when the universe was only 300,000 years old at that time matter and radiation were the matter was so hot it was 3,000 degrees that matter and radiation were in equilibrium but after that time the matter cooled down neutral atoms formed and the neutral atoms were transparent to the radiation so the radiation could move throughout the universe unimpeded and in 1965 or so that radiation was detected for the for the first time by two people who didn't know what the hell they were doing they had a radio telescope and they looked up and they saw noise they didn't know what the noise was they they cleaned out it was an outdoor telescope they cleaned it out it had a white dielectric material which was pigeon droppings they cleaned that out the noise went down but it was still there and it bothered them till some physicists down the road at Princeton University told them they discovered the noise from the Big Bang and those people who discovered it and didn't know what the hell they were doing won the Nobel Prize because you don't have to know what you're doing to win the Nobel Prize you just have to do it okay they discovered the afterglow of the Big Bang the first definitive evidence that the Big Bang really happened and the Big Bang did really happen and if you meet anyone who does who doesn't thinks it happens ask them if they also think the earth is flat because there's as much evidence for one as the other okay so we build detectors now and this is in the South Pole why because the South Pole is dry and high and so you can the atmosphere allows the radio waves the microwaves to come in in a certain region in the frequent of the frequency band very effectively so this is this is at the South Pole there's a detector called bicep and then there's another telescope called the South Pole telescope they're looking at this this is it's interesting to me this is um this is liquid helium which is delivered it's cold at the South Pole in case you wondered but it's not cold enough in order to make these detectors work you have to cool them down to almost absolute zero and so we have to we have to ship down liquid helium to the South Pole in the summertime this is the summer why this surprised me when I first learned it maybe it won't surprise you but it really surprised me when I first learned this many years ago don't send planes down to the South Pole in the wintertime because we're worried that if the plane lands it won't be able to take off again so that means if you're down in the South Pole and it starts to be winter you're stuck there for the whole winter this that's why this is one of my favorite pictures this is this is a picture from the this telescope at sunset sunset happens once a year in the South Pole because in the summer the Sun is always above and the winter the Sun is always below so this is that this is the moment when it begins to be winter which means if you take this picture you're stuck there for six months which is why I was probably taken by a graduate student because now the ones we send down they're innocent but this detector and others like it may detect gravitational waves from the Big Bang and I want to talk about that a little bit and I'll even have an equation because I felt that there are students and faculty so I should have at least one equation in this so here's here's what we think happened at the beginning of time the universe is expanding it's getting bigger and bigger and bigger and if we go back to a very short time after the Big Bang a millionth of a billionth of a billionth of a billionth of a second after the Big Bang we think something very strange happens for reasons I'll talk about in a moment we think that the size of the universe increased dramatically in a millionth of a billionth of a billionth of a billionth of a second the universe increased in size in volume by 10 to the 80th it went from the size of the entire visit what is now the visible universe today went from the size of being about the size of an atom to the size of a basketball now if gravitational waves are produced when when extreme movement it matter happens when our whole universe goes burp that should produce gravitational waves but in a very particular way and I want to tell you I want to show this is the the equation part so some you can sleep now and then in a second you can wake up there's a miracle it's not really a miracle but there's something amazing right now maybe some of you who work in physics departments are working on on the development of quantum mechanic imputing to use the weird properties of quantum mechanics and manifest them at human dimensions because we tend to think quantum mechanics only operates at small scales in fact you are all remnants of quantum mechanics if inflation happened because inflation happens because quantum fluctuations become us do we think what happened during inflation is that there was some field like an electric field but a different kind of field that gets stuck in a certain place and it stores energy and there's energy throughout space and the field gets stuck it's like a it's like super cooling water on a cold day like today you'll see when cars go on the road you'll see liquid water it's because the cars are stirring it up even if it's below zero it'll still be liquid but the minute the cars stop stirring it up suddenly it freezes forms black ice in that moment when it freezes it it releases energy because the preferred state it wants to be is ice and you've been stirring it up and giving energy and when it freezes it suddenly releases energy it's called a phase transition we think in the early history of the universe that our universe got stuck like water it was in a phase that stored energy and then when that energy was released all that energy got turned into heat and particles and the hot Big Bang happened but during this time when that energy was stored that's when space suddenly expanded very fast now how do we know when the transition happens if the universe is staying there if there weren't for quantum mechanics it could stay there forever the phase transition might never happen but quantum mechanics tells us that things are fluctuating all the time and fields quantum fields fluctuate all the time and I'm not going to go into this much they they change this field is wiggling back and forth depending upon the expansion rate of the universe it turns out and if it's wiggling back and forth in one place in the universe it can wiggle so far that it falls over the edge and releases its energy so here inflation ends a little bit before here but if inflation ends a little bit but here before there it turns out the density here is a little bit lower than it is here the energy that's released is more here than there because this happened later than that and that means you have small fluctuations in matter and energy but those small fluctuations in matter and energy if you have produce a little more matter here than there it's denser here and there that collapses to form a star and planets and people we would not exist if it weren't for those quantum fluctuations you are quantum fluctuations you're remnants of quantum fluctuations if this is true it's a it's a it's something we don't talk about enough but it's an amazing it's an amazing remarkable mirror miracle and we can calculate how much it is it doesn't matter but it really means that if this is true then all of the stars and galaxies and planets and aliens and people that and everything came from quantum mechanics in the earliest moments of the Big Bang but gravity we think is also quantum mechanical and if there are fluctuations in other fields they'll be fluctuations and gravity in the early universe during inflation and those fluctuations during inflation will get frozen in as gravitational waves after inflation ends so the picture of the universe that we have if this is right and this is hard to read but it was from a scientific American article I wrote a long time ago and I spent a lot of time with the artist so you have to look at it but but we think there was the Big Bang that inflation happened in the universe suddenly blew up and then it started getting bigger and bigger and this is the time of the Cosmic Microwave Background and what happens during inflation you produce gravitational waves of all frequencies a period of one second ten seconds a century a thousand years a million years what happens well let's say you have a gravitational wave that has a period of one second but the universe is one tenth of a second old well the gravitational wave that doesn't start to vibrate yet space doesn't start to vibrate because it's not there's not enough time for it to start to vibrate but when the universe becomes one second old the gravitational wave starts to vibrate space starts to vibrate and then that gets dissipated away it disappears with time then maybe I have a gravitational wave with a period of one century when the universe is 100 years old that gravitational wave starts to vibrate and then it dies out and then maybe I have a gravitational wave of period 1,000 years when the universe is 1,000 years old it starts to vibrate but then let's say I have a gravitational wave of a period of 300,000 years which is the moment this microwave background forms that will produce a remnant signal in the microwave background and here's how the microwave background happens because there are free electrons the universe is hot and electrons are free they're not in atoms radiation is all around it and the electrons scatter the radiation to us and that's what we see is the microwave background but if you have a gravitational wave of period 300,000 years when the universe is 300 thousand years old that looks like the whole universe for that electron and if the gravitational wave comes by the universe gets a little smaller in that direction and a little bigger in that direction as far as the electron is concerned and that means the universe looks a little bit hotter in that direction and a little bit colder in that direction and that means the gravitational their electron will scatter more radiation coming from this direction than that direction and that means the radiation we see will be polarized if you think about an electron and you see more radiation intense radiation coming from this direction in that direction you can calculate that the the scatter radiation will be polarized so if we can look for polarization in the microwave background it'll be a signal of a gravitational waves because the gravitational wave will squish space in this direction and expanded it in that direction it turns out the polarization was a little more complicated but I'm not going to go into it here so what we could in principle do is look at the hot spots and cold spots in the microwave background and this we've been able to actually measure these hot spots and cold spots we've been able to measure what we think are the fluctuations coming from the Big Bang in this microwave radiation a Nobel Prize was given for that for this measurement the hot these hot spots are about one one ten thousandth of a degree hotter than those cold spots so it's hard to measure but it was measured but if we can also measure the polarization of the radiation maybe we could see gravitational waves so this is the polarization should be random if there are no gravitational waves if they're gravitational waves it doesn't look very different it's really hard to see the difference it's about ten thousand times harder to see the polarization from gravitation due to gravitational waves than it is to see the temperature difference but experiments are being built at the South Pole now that may be able to detect that and if they detect that they will be seeing gravitational waves not from black holes at 1.3 billion light years away but they'll be seeing gravitational waves produced when the universe was a millionth of a billionth of a billionth of a billionth of a second old they will be measuring what the universe looked like at the time of the Big Bang and will be and this signal can only come from inflation and if that's the case we'll be able to experimentally measure what happened when the universe was born and what makes that interesting to me is not just that we're able to do that but it turns out because inflation predicts that the universe gets much much bigger much quick more quickly our visible universe could just be a small part of what we now call a multiverse and it could be that one region ends inflation now creating the universe we see but there could be other regions far away which have still inflating and haven't yet ended inflation and there could be many many different universes and in each universe the laws of physics could be different when you once Uli's inflation this is this idea called a multiverse lots of theorists are thinking about it but it sounds like religion or philosophy not science because who could measure other universes we'll never be able to measure them directly but if we could measure gravitational waves from inflation we could see if inflation happened and we can infer indirectly that there are other universes we can infer indirectly that maybe there are other universes in our universe our galaxies and other universes there may not be we could turn metaphysics into physics and anytime you could turn metaphysics into physics it's a success because metaphysics is just talk physics is real on the scale of things religion is down here and and metaphor thank them that's true metaphysics is here and physics is here and anytime you can go in that direction it's a good thing so we're on the threshold in your lifetime maybe of being able to detect a signal from the Big Bang and maybe begin to learn about the origin of our universe that's the the astronomy and physics of the 21st and 22nd centuries and you will be able to participate in it and so I think when we look at this night sky as I say it inspires me I hope it inspires you but it's just the tip of a cosmic iceberg what we can see is far from all that there really is earlier today I talked about dark matter but the universe is full of things there's far more in heaven and earth than are dreamt of in our imagination and if we keep looking we'll be surprised and I hope in your lifetime you will have many many surprises thank you very much [Applause] thank you thank you let's and spoken across into a new direction and now we are continuing our program and now we can possibility to ask professor Krauss yeah like any longer than I think questions yeah I took longer than I thought as often happens but let's start time for some questions are things that alright it's miss time these have about oil to won't take too long people have to go to the bathroom but we'll take some questions like did I see a hand is there a microphone or do you want people you must go to the you have to go to that microphone so people can hear you and has to be in English or if it isn't someone has to translate now you must go and position the corneas ok microphone hello yeah so it's ok with English okay so can you hear me I can hear you but ok ok so it's possible I would like to ask three questions maybe let's see if your first ones any good yes ok the first question about the detection of the black hole : so if this event was detected right after the turning the detector on so that probably means that this event is quite an often in an hour it's a very good session I'm gonna give you I'm gonna allow you one more after that because it was a very good you're right we predicted what's amazing and it still amazes me as well as people thought that these black holes might exist and we and in order to be able to get the National Science Foundation to give a billion dollars to build it they have to say well probably if this detector gets to the sensitivity we might detect an event every few weeks or every month we think they're that frequent but it was a lie I mean it wasn't a lie it was the best idea we had but no one knew we were right what's amazing is as far as we could tell there may be in seven or eight more events that have been seen they probably occur on a level that is about what we thought every month or so they were very lucky to see within the first hour but they've seen a few more but that but the best event they've ever seen the gold played an event the best one so far has been the very first one so it was just blind luck it was you know a lot of science happens by luck as much as as anything else and they were very very lucky but so we think that indeed we now know and we didn't know before there are galaxies and the universe is full of objects that are solar mass and bigger than our black holes and maybe that will explain why there are large black holes in the center of galaxies it's it's a whole new field of study that is just beginning second question second question if I understand correctly from the construction of the detector it can only say that the gravitational wave they exist but not to direct the direction so how can you say about the direction good well with one you can't but if you have two on different sides of the earth and you measure time differences between the signals seen here and the signal seen there so let's so there's one in hanford but there's another one in europe called virgo and with the newt with the neutron star if you measure the time difference you can sort of tell what quadrant of the sky if you do three you can do better you'd use triangulation just by measuring time differences between this signal that's sitting on that signal you could say which direction it's coming from and so when virgo with original detector you couldn't tell really very clear you could tell which hemisphere but with for the neutron star event which was seen by virgo as well as like oh you could actually do a region of the sky and the more gravitational wave detectors that come online the better we'll be able to do in but you're right with one detector you can do only marginally you can sort of tell where and that which hemisphere it is okay but but from the amplitude and the period we could tell how far away it is we could because we solve Einstein's equations and we know how massive the stars are and we can see from the strength of the signal how far away the star the star must have been so that's how they know it was 1.3 billion light years away but we don't know where it was really but it's a very good question I think I'm only gonna give you two because they're two more people behind you you can look wait and you can come back to the third okay okay thank you and I think it will be interesting if you say what is your affiliation and in a sec okay my name is Andrey the Sapolsky from the Institute of Physics yes academia science of Ukraine that's a question okay what is your affiliation please my name is Eugene and what what did you ask me what is the relation organization actually I have already finished University ten years ago so okay I'm just working well welcome back yeah your question please okay the first short can I sign your book after the lecture yeah okay that was easy and now is it now as a question mr. Krauss what do you think about our possible possible encounter with extraterrestrial civilization is it dangerous for us like for example Stephen Hawking said about that it can be like well Stephen said lots of things look the likelihood the likelihood of ever ever interacting with an extraterrestrial civilization is small even if they exist first of all we don't know we may be alone in the universe we don't know we don't know what the probability of of what we don't we don't yet know how life forms here on earth we have ideas about about about what process has led to the development of life and then we don't even know what the likelihood that intelligent life forms is so it could be very very rare but even so the universe is very large even our galaxy's very large and I once worked out in one of my books the likelihood of detecting life in our galaxy even if it exists intelligent life is still very remote so I'm not worried first of all I think it's highly unlikely but even if we did detect it I I think I disagree with Stephen and and other people who are worried about this because I think the highest likelihood is detecting civil if you could detect a civilization that was intelligent it would probably have been technological much longer than us which means that it would not be interested in us at all I mean we wouldn't be a threat my moreover who the hell cares because they're not going to come visit us we we may we may find out about extraterrestrials but but they're not sending spacecraft to us we just can't send spacecraft throughout the galaxy at anywhere near the speed of light it's just impossible okay and so we're not being we're not people aren't being kidnapped with weird sexual experiments by aliens no matter what you read in the newspaper and so I don't think it's a worry at all and I think Richard Fineman put it well he said the the experience of extraterrestrial sightings UFOs is probably much more likely due to the known irrationality of humans rather than the unknown rationality of aliens okay no don't worry okay good okay well good afternoon dr. Krauss thank you so much for the lecture actually and my name is Igor I'm still studying at school so good maybe my question will be a little bit stupid but no no there nope nope okay so I read that Hawking radiation is like a hypothetical versus yeah so how could we theoretically detect it well okay so Hawking radiation what what Stephen Hawking did that made him famous in the scientific community was the realization that classically black holes are are so dense that not even light can escape why because well from Earth in order to adore escape the gravitational attraction of the earth you have to send something up at a speed of 11 km/s any of the introductory physics students here could calculate that I hope because you know this isn't the United States and and so but if I added a little bit more mass to the earth than the escape velocity will increase and if it gets more massive still the escape velocity increases and if I get enough mass in a small enough region the escape velocity is faster than the speed of light but nothing can travel faster than the speed of light so not even light can escape light comes back on itself so nothing can escape a black hole but what Hawking discovered is due to quantum mechanical processes near something called the event horizon of black hole particles can actually escape and the black hole will evaporate for a solar mass black hole the time it takes it to evaporate will be far longer than the age of the universe but for a small black hole it can evaporate in in an instant but the problem is the only black holes that evaporate quickly are the small black holes but you can't see small black holes unless they happen to be in the room and there aren't any so the likelihood of ever directly detecting Hawking radiation is almost zero it remains a theoretical prediction and it's but it's a very important theoretical prediction and I've worked on it because if if black holes do radiate then there are various paradoxes that happen because a you can have material fall into a black hole and then you don't know what's in there and then the black hole disappears and where did all the information go in quantum mechanics the information can't disappear but if the black hole disappears that the information has disappeared so it appears to violate the laws of quantum mechanics and that's why many of my colleagues are fascinated by the idea of black hole evaporation because it appears to violate the tenets of quantum mechanics and maybe we'll learn something about quantum gravity but unfortunately it's likely to remain pure theory and that's why right now there's much more heat than light if you are being talked about and and most of it is just talk yeah thank you thank you very much thank you it's a good question okay good evening my name is Mihal I'm from Institute of physical technology from kpi I want to ask you a question about warp engines or Alco or al khabiri engines in previous 30 years there was bunch of series about this kind of stuff and I want to ask you a question how do you think my can be achieved some results in this in following years or maybe case in a century sure I wrote about that many years ago in the physics of Star Trek book that I wrote the idea is you know you you've heard a Star Trek right okay so the problem with science fiction it well it's not the problem the problem with real life is that we can't travel faster than the speed of light and the galaxy is big so we're 30,000 light-years from the center of the galaxy and therefore if we want to explore the galaxy take 30,000 years to get there that does not make for exciting television 30,000 years a long time so they had to come up with something that allows you to go through the galaxy faster than the speed of light they called it warp drive and it was easy for the writers but it's not so easy in the real world but it turns out when we say that you cannot travel faster than the speed of light we're lying we have to be a little more careful you cannot travel through space faster than the speed of light but space can do whatever the hell it wants and space can expand at far distances faster than the speed of light so if you could manipulate space with general relativity you're allowed you could be standing still and still moving at the same time we're doing that right now we're standing still relative to each other but relative to an audience in a university on a planet around a star at the other end of the visible universe we're moving away at the speed of light and that audience in that theater in that planet around that galaxy they're also at rest so their arrest and we're at rest but we're moving in the way of the speed of light why because the space between us is expanding so fast so if you can manipulate space in principle you could imagine traveling faster line and this is the idea is quite simple so you want to get from here to the nearest star it takes a hundred thousand years for a rocket to do it say let's say cook with conventional rocket Voyager will take that long to get in there a star but all you have to do if you can manipulate space is to arrange for the space between you and the star to collapse in a fraction of a second and the space between you and the earth to expand in a fraction a second and then you're there at that you didn't move but the space did all the work and now you're near the star near four light-years away from the earth it sounds easy not so easy in principle the law the equations of general relativity allow that to happen the question is is it possible in practice and the answer is probably not if you could do it the amount of energy that would be required is large it's changed we used to think it'd be greater than the mass of the visible universe then it was just the mass of the galaxy now maybe it's just the mass of the earth but it's not practical even if we could do it we don't know how to do it we don't we don't know how to create the type of energy in the laboratory that would Mase pace expand we can create the type of energy that make space collapse that's us but the kite that makes it expand we don't know if in principle that can be created the laboratory but even if that were the case by the way just to make take away all your hope you still can't travel faster than light namely let's say I want to go from here to the nearest star well to make space collapse between me and the North Star I'd have to populate it with the right amount of energy but the only way I could do that would be to have with rocket ships dumping the energy there and those would happen at lower that you know they can only travel slower than the speed of light so to set up the experiment would take a hundred thousand years then poof what would happen like that but from the time you started the experiment till the time you made it happen you never you don't win anyway so it's wonderful for science fiction but I wouldn't go into business trying to make one okay okay good thanks a lot sure thank you I'm so just Mullins mr. Krauss we have a limited time before alien connection and maybe we can they give more small answer okay much smaller answer I talk too much is what he's saying okay I'll be quicker yeah hello my name is Yuri I hope you enjoy being here in gear I'm enjoying talking to you mentally I'm not thank you I'm not physicist I'm an engineer that's okay so my so my question would be more practical when we have some waves in air for example it changes the density of oh that's good yes okay go on so when we have those gravity waves it should have changing the density of the matter of the space it does that's why space gets hotter in one direction then another cosmic background it should affect the optical properties of the light and probably this sensor would not work well it wouldn't work it your point is well-taken on every time I thought about gravitational waves I got confused for the same reason you think that the light would change in such a way that you wouldn't see the effect but because the two beams are going through two different gravitational fields they change it if one beam could never do it but because the two are experiencing different gravitational stresses they will interfere differently and if that's the reason you get interference because for a long time people even Ray Weis have convinced himself that maybe the effect wasn't real that the effects would cancel out but because the two beams are going through two different two different gravitational trajectories they do interfere but it's a very good question you should become a physicist okay I think you'll try thank you okay yes you can put it down there we go okay hello my name is Angelica I am said in Applied Physics in this University and Wow enormous numbers but don't you think that your researchers are it will take place in more mostly in philosophic not in physics in what that what that what I did wrong I think it's more philosophical than physics I hope not no because the difference between philosophy and physics is again if you can measure it it's physics and if you can make predictions philosophy look I know people know I've made fun of philosophy often and I like to because it's easy but but the point is philosophy is useful for a reflexion about trying to think critically about what we understand but making predictions physics is a very mature field and and we can make very mature predictions that can be tested at the level of 10 decimal places and so that's not philosophy and so we can make put the fact that we can predict the fluctuations in the microwave background to one part in 100,000 s we can calculate it what is that but it becomes philosophical if we begin to make predictions about the origin of the universe right now that's that leads to a whole bunch of philosophical questions and those are interesting to ask but what interests me far more than those philosophical questions is the the physics answers I mean we can philosophize about what happened before the Big Bang or whether there are many big names it's wonderful to talk about but who the hell cares what I'd like to know is could we measure what happened at the Big Bang that's what interests me and I don't know if I'll know the answer and I don't know if we'll ever know what happened before the Big Bang but we'll never know unless we try and so we just keep trying that's all thank you and my second questions a question okay okay okay we have a big bang and then a star dust yes I think that it's a little bit stupid to search gold just a nurse don't you think so it's stupid to have called just on earth gold just a nurse I don't understand what you said if if we have gold from the Big Bang we have we don't have any gold for the Big Bang we have to call the only place gold is created and the heavy elements we think are the collision of neutron stars and and that was a that was a prediction and what's amazing to me is that prediction was verified explicitly when we observed the collision of those neutron stars exactly the radiation that came from the decay of radioactive nuclei that was predicted was seen so it's amazing that our theoretical ideas about where gold and the other elements heavier than iron were created was exactly validated by observation that turned philosophy into physics answer the question at Los Deacon our lecture okay we're probably okay yeah okay we've got it well maybe we should end at 3:30 is that okay if we end at 3:30 just so people know they're getting restless can we and it will end in ten minutes okay so Noam and then I'll answer questions in private but you're not stuck here yes good day professor Krauss hi it's a great pleasure to have you here it's a great pleasure being my name is Alexander and I'm not a student I just came here from work good luck my work place the distortions of the space-time that we measure are your face closer to the microphone sorry no distortions of the space-time that we measure are extremely tiny tiny yeah and also we should hear a lot of noises produced by driving cars around the detector maybe I mean there's an incredible I mean it's amazing that you can in the midst of all that noise you can see the signal it's again if you'd asked me if I ever thought they could do it I was sure they couldn't no I I just as I know scientists look for patterns modeled before of the known type known types of collisions is it possible to to find a signal to detect a signal from unknown type of collisions for example aliens may be making fun ways no it's a very good question the answer is if there's a very there's an old story that I like to tell while it's a famous story none of you have ever experienced this but let's say you get drunk and you're in a bar and you walk out of the bar and and you're hobbling around and you've lost your keys where do you look you look under the light post why not because the keys are going to be there but it's the only place you'd be able to see them yeah so if we're physicists what we do is we always look under the lamppost the first thing we do is we look for what we expect okay cuz that's easy the second thing once you know your system is working and you know what to expect then you could begin to look for the surprises so the answer is yes maybe we'll see something we didn't expect in fact everyone hopes that but we don't know what we don't expect and so we just look but the answer is in order to be separated from known sources of noise in our on earth you'd have to see the same signal and many detectives at the same time and if you saw something that was you know very very different than a gret that then a colliding star then maybe it would be a signal from an alien civilization but you know what there's a lot easier ways of signaling I would do this with my laser beam okay it's a lot easier to do that then make a gravitational wave but maybe but maybe sufficiently advanced civilizations can manipulate space enough to do that who knows you never know till you look so it's a good question okay thank you so much yeah sure hello my name is Vlad I'm not a student anymore I have a question regarding doom for more videos to please sorry Mitch University National Aviation University I'll ever since 10 years ago to man it okay okay doesn't matter what matters to him doesn't have to be okay dooms close in how much time it shows right now how much time what it shows right now how much time I didn't understand how much time watch dooms clock Oh Doomsday Clock oh yeah okay I'm right okay well I've been involved in something called the Doomsday Clock I I headed the Bulletin of the Atomic Scientists for many years or at least the committee this group of sponsors and it's now two minutes to midnight which is as close as it's been any time since 1953 so what we said is that the the threat of nuclear war and climate and the effects of climate change and maybe other kinds of terrorism is is very great right now and we think it's a very dangerous time in the world now what do we meet why do we do that not to scare people but to tell people the only way we're going to change things the only way we're gonna change things is if you get it interested and you get worried and you make your government's change the only way they'll deal with climate change is if the public starts to complain the only way they'll start that they'll do nuclear weapons agreements as you may know my idiot president has just abrogated an arms control agreement with Russia the only way that's going to change is if the public gets involved and the only way the public's gonna get involved is if they begin to worry about it so one of the reasons we produced the Doomsday Clock since 1947 is that the first people who set the Doomsday Clock where Albert Einstein and Robert Oppenheimer and I was honored for a decade to head that group I no longer as of about five months ago I no longer had that group so I don't know what the Doomsday Clock will be set at next year but I was very honored to be involved but the point wasn't to scare people it was to just get people into it get people to act because it's only the government's don't lead they follow even dictatorships follow and the only way to make changes have the public make the change and so that's why we did what we did okay hello I'm on the second year studying here in kpi University my name is Melanie Kola and I would like to ask you a question about string theory can we prove the string theory using using gravity waves well look the point is in order to in order to prove well in physics we don't prove things by the way we disprove things now I can never prove an ideas right I can only prove it's wrong what's left over may be right but it can always a change but the only way to to disprove string theory would be if it made a prediction but since it hasn't made any predictions then it's hard to disprove it and it's not a fault of string theory it's just it's a very complicated idea that may or may not have anything to do with reality but because it deals with a phenomenon that are so esoteric that even if we understood the math and we don't yet then it's not clear we'd be able to make predictions that could be technical maybe if we could probe the very beginning of the Big Bang at the level I talked about maybe we begin to test physics that might be relevant to string theory but I wouldn't hold my breath right now calling string theory a theory is really an insult to the word theory that's nothing against string theory but theory and science is something that's been tested oh like the quantum theory theory of gravity I mean these are ideas that have been tested over and over again string theory is really a hypothesis it's a very fascinating mathematical hypothesis that maybe relates to the universe in which we live and has good is well motivated on certain grounds but it's far for unfortunately it's not even yet well enough to fall to find to be able to provide tests that we can do to know if it's false so it's not yet even a theory Thank You philosopher and thank you for your species was really interesting thank you and thank you for the question please just a moment I want to say that we have a limit of time Maxim for four o'clock and I my house' to your questions will be more shortly and i'm gonna go in public for another three or four minutes until i get to that young lady and then who's standing there unfortunately you guys I don't have time but I'll answer your questions in private but but sorry so after after the young woman in the heart sweater that's where we'll end so let's go please ok ok next question hi - stem I'm from this planet ok yes but I am from the kapowie I mmm physics Chemical students ok how long I'm interested astronomy amateur astronomy I have one question probably tell theoretical physics yes yes electrical physics already believe in the exist of graviton but how how can we prove the existence gravitons is a question yes actually that's it okay I'm gonna mean faster now I'm going to anticipate your question it quantum mechanics every wave is associated with a particle if gravitational waves exists then the quantum gravitational wave called graviton should exist now what's really interesting is there's no experiment you can do on earth to measure gravitons we think but the universe may allow us to measure gravitons and in fact if you could measure gravitational waves for inflation i and a colleague of mine Frank will check who won the Nobel Prize have shown that you could prove gravitons exist in principle if you could measure gravitational waves from inflation we think you can show that gravitons exists so that may be the only way to show experimentally the gravitons exist that's why I'm so interested in that that's the quick answer I'll answer more after that but I want to get through ok yes ok thank one more questions one question well I can't let you ask another question now because I want to get to you hey hey you don't get mad because I'll be here you can ask me the question of private afterwards okay okay mm-hmm hi I'm a student of KPI and my question is about the false vacuum false vacuum yes and actually when you were talking about that where did the universe get the energy to actually push the state of construction consideration of energy well the neat thing was okay look when when the heave ment mentioned the word false vacuum what when I showed you inflation I showed you that you were we were stuck in a state and then it released the energy that's what we call a false vacuum in physics okay so universe gets stuck in some state that isn't the true ground state of the universe where did the energy come from turns out it's great it's the ultimate free lunch because it turns out that while the well empty space has energy in that case that gravity has negative energy and the to balance and you can have zero total energy so the total energy of the universe can be zero and that's why I wrote a book called the universe from nothing because it turns out the total energy of our universe may be zero the positive energy due to galaxies and everything else or in early times due to the energy of empty space can be countered by the negative energy of gravitational attraction the two can add up to zero and if you look at our universe it looks like the total energy is probably zero so it's the ultimate free lunch you can get a universe full of a hundred billion galaxies from nothing without violating any laws of physics and without any supernatural shenanigans okay okay that's the quick answer yeah hello my name is Dima and I want to ask you about sounds of Big Bang which some mechanics here but didn't get that was Big Bang like how does related to radio waves and how can they even accurate well I not sure I had it should you 100% but the point is that when the Big Bang happened after the Big Bang the universe was very hot and then over time it cooled down and matter and radiation were in equilibrium because you couldn't have atoms because every time you a proton captured electron and would get kicked out again by the radiation so you had I annihilated radiation but when the universe cooled to a temperature of 3000 degrees protons the nuclei of hydrogen could capture electrons to make neutral hydrogen neutral hydrogen is now transparent to that radiation so the radiation that existed at that instant has now been able to move through the universe unimpeded so that radiation which was 3,000 degrees has cooled now to a temperature of 3 degrees and if you asked what frequency would the radiation having a temperature of 3 degrees be it would be in the microwave band so we look at microwave radiation and we see it in all directions and that's the remnant of the radiation that the hot Big Bang radiation that got decoupled from matter when the universe was three thousand degrees in temperature which happened at a time in the universe was three hundred thousand years old and that's why that picture of that microwave background radiation gives us a picture of what the universe looked like when it was three hundred thousand years old that's the quick answer okay thank you sure two more questions okay I am a physics student and my question is regarding say the phone please wait sorry what No okay sure how many polarizations are in the gravitational waves oh well gravitational waves have two polarizations days then I have another question we old you know I knew that was a trillion it's already done right um is it tens of like particle and has been - yeah I know turns out gauge invariance reduces all the extra degrees of freedom just like the photo yeah I mean I know you have a smart question so I'm gonna give you a smart answer the photon should have three degrees of freedom is after all it's a vector field vectors have three but but it turns out the symmetries of nature something called gauge invariance reduce one of those degrees of freedom so photons have only two polarizations it turns out there's a much bigger set of gauge invariance for gravitational waves that take something that should have eight or nine degrees of freedom and and because it's a tensor and reduce it to just two polarizations and that thing is called gauge invariance okay that's the mathematical answer to your question okay so once you use the group of symmetry one what is the group of symmetry well you know the important halves you want it's conformal it well it's it's the general coordinate of variances of general relativity which is which is what which is a gate turns out to be a gauge symmetry I know what is the gauge group of symmetry oh and well at bsl-3 C I guess each term is hey well we can talk about that okay there's something that anything to anyone here so we'll have that calm oh you say about on the classical fertilization please not about religion assertion okay let's last question okay it better be a good one you said that multiverse mesh may exist if there are any other universe many modern science predict how what makes it look like what might be like what might what be like I'm sorry I didn't hear what well what what may be other universes be like who the hell knows no seriously because this is all speculation right now and and it could be it could be that there's only one set of laws of physics and then the same after inflation there's only one possible state that the universe can come into and every universe it forms has the same laws of physics or it could be that they're all different it could be that there are every possible kind of laws of physics exist anywhere we don't know once again the only way to know is to try and do the experiments to try and understand the nature of inflation and the only place to find them to understand the nature inflation may be to look for gravitational waves from the Big Bang or to look for new exotic physics and particle accelerators so the answer is it's anybody's guess and it's your job in the next generation to find out thank you very much - thank you [Music]

Channel: ВТЗН КПІ ім. Ігоря Сікорського ВТЗН

Views: 161,980

Rating: 4.7316594 out of 5

Keywords: Kiev Polytechnic Institute (College/University), КПИ, НТУУ, КПІ, Київський політехнічний інститут, Киевский политехнический институт, krauss, phisics, gravitaion, waves

Id: p976iXeDH7w

Length: 87min 33sec (5253 seconds)

Published: Sun Nov 25 2018