Cosmic connections: the Universe and You with Lawrence Krauss

This lecture is brought to you by Science and Cocktails and ECSJ2017/Danske Videnskabsjournalister/EUSJA. hi hi can you hear me okay well it's going to be hard to follow that that was really the summary of everything I wanted to say but I'll try it's a real pleasure to be here this is an amazing event an amazing venue I just flew in this afternoon and and this is waking me up already so that's good so I hope to have fun tonight and tell you a story that's that will change maybe a little bit of your perspective of the place in the your place in the universe this by the way is the universe in case you wondered this is a picture from the Hubble Space Telescope and every dot in this image except for that one is a galaxy not a star there are a hundred billion galaxies in the observable universe each containing 100 billion stars and we're on just one of them and even that is an amazing discovery I wanted time to talk about that but a hundred years ago we thought there was one galaxy in the universe we now know there are over a hundred billion and that just gives a sense of how things are changing and every day we discover new and amazing things about the universe and what I want to talk about is how it's not just out there how you're connected to the universe in ways you may never have imagined but I want to begin this story as a story so like good stories I want to just say at the beginning it's the best of times and by that I mean that the Large Hadron Collider is operating in Geneva and has not created a black hole that destroyed the world so that's very good but at the same time it's the worst of times as we've seen in that last video and and and the important thing about cosmology and science is it can take us away from these local awful things because this too shall pass this is just a speck in a cosmic history so as miserable as this may be it's just a moment and so anyway let me begin by taking you first to a connection that was that was talked about in it's in the video a little bit but maybe put a little more content than just the fucking the the so I like art and it's great to see our here and it's wonderful that there's an artist doing this right now even as I speak one of my favorite artists is a sculpture Rodin and I was in the Rodin Museum in Paris once and I started to think about something I later wrote a book about it about the fact that when you look at Brennan's art that they're beautiful moments that are captured and and there's a famous statue that where dad has a kiss and I was looking at that and I think you're thinking that that kiss was immortalized in stone forever but of course it's not forever and the stone hasn't been around forever the stone has only been around for millions of years and I started to think about what is forever what's eternal is there anything that's eternal and nothing is but but the closest thing of course in some sense is our atoms and our atoms have been in a lot of interesting places I have my cocktail here which unfortunately is empty and no one has refilled it but in a case maybe that'd be a message that people I was getting that one that bubbles if you want to bring me another the but my mother used to tell me when I was a kid and I drank a glass of picked up a glass she said don't you you know don't touch that you don't know where it's been and she will be amazed by the real true story of every atom in your body because every atom in your body as I say is it's just been around on earth for four-and-a-half billion years but but it's been around a lot longer than that and in fact the actual atoms have not been around since the beginning of time in the beginning of the universe are only hydrogen atoms and and a little helium and some lithium which is important for some of you I guess but but but for the rest of us the carbon the nitrogen the oxygen is the important stuff and that hasn't been around for a long time and the first connection I want to bring was your connection to the cosmos what do you know is this one of the ones that bubbles okay okay good okay not the same one but it'll do it's a little stronger okay the talk may go on longer than I intended but um so this this is uh this was the first thermonuclear explosion on earth it was the mic explosion in 1952 November 2nd that 7:00 in the morning I think and briefly of course it wasn't done as a science experiment it was done as an experiment to destroy things and and and great okay here we go okay well I can have my work cut out for me okay I'm not responsible for what I do after those okay so it destroyed a Pacific atoll in a microsecond in this different thermonuclear explosion but interestingly enough in that in that microsecond every element that was ever existed in the universe was also created because thermonuclear explosions involved nuclear fusion and that's the process of power stars in the Sun and that's how your atoms came to you because the carbon the nitrogen and the oxygen the iron was only created in the cores of stars it wasn't created in the Big Bang and the question is how did it get to your body and it got to your body thanks to stars and stars that exploded this is uh this is an image from a nearby galaxy about set about 70 million light years away and it's a galaxy just like our own if it were if this was a milky way we'd be sort of located sort of there in a boring suburb not Christian or anything but but where the earth is around and the Sun is around our galaxy and but this is another galaxy and what you notice about this galaxy of 100 billion stars is maybe ten billion stars in the center but you notice this bright star here and this star is shining with the brightness of the entire center of that galaxy which is surprising because there are 10 billion stars in there so the first thought you might have is that this star is just in our galaxy and it got in the way of the picture but that's not true it's a star at the edge of that galaxy and it's shining with the brightness of ten billion stars why is that it's a star that's just exploded a supernova an exploding star the the brightest cosmic fireworks anywhere when a star explodes it shines brightly for about a month with the brightness of a hundred billion stars and stars and their lives some of them as exploding stars and it's important for us that they do explode because if they didn't we wouldn't be here because all the nuclear materials that are produced during the lifetime of that star are then it sent out into space now we actually can observe exploding stars fortunately for us stars don't explode too often once every hundred years per galaxy fortunately they explode however because they didn't we wouldn't be here now how can we observe stars that they explode only once every hundred years per galaxy the answer is the universe is a big and old place and rare events happen all the time I'll stand for you to finish that picture and then I'll move okay good anyway so once 400 years for galaxies well there's two ways we could study at first we could assign a graduate student to each galaxy because a hundred years it's about the right time for a PhD so that's okay and you know if the graduate student dies it's okay because students are very cheap so that we don't need it but there's another way and that is to realize that okay because the universe is big and old these events are happening all the time in tonight you won't be able to see if it's cloudy but if it ever gets clear in Copenhagen at night you could you could take a small hole with your hand and look up at the sky where they're no stars and take a hole that big and with the largest telescopes in the world we have in chile if you looked up in that dark spot you'd see about a hundred thousand galaxies in that little region and that means if you look at a hundred thousand galaxies in a given night and you work things out once every hundred years for Galaxy you'll see a few stars explode and astronomers do that they apply for telescope time and they look out and if they can see enough galaxies on a given night they'll always see a star explode and we can study those stars and we've been able to feed learn about them and we've been able to use them to study the universe that's in some sense a different lecture but these stars when they die they create other star systems this was by the way the most recent supernova that we've seen not in our galaxy because the last supernova that was seen in our galaxy was about 400 years ago and amazingly the reason for that is because most of our galaxy is dust and we can't see the exploding stars in our galaxy they get obscured by dust but if we look at other galaxies we can see them but this one was in a neighboring galaxy the Large Magellanic Clouds which is you can see in the southern hemisphere and this star exploded in February 1987 and there are other stars that have exploded this is the Crab Nebula there was a star that exploded about a thousand years ago that was seen that could be seen during the daylight on earth when the star explodes in our galaxy and it's interesting to me to think about this because this was in 1060 something I forget the exact year but there's no records in Europe of That star exploding yet in China it was there was a record Chinese astrologers saw a guest star in the sky and reported it to the Emperor and said it brought good tidings because of course that's what they want Emperor wanted to hear which is what religion is all about and um and but it wasn't recorded all in Europe and I think one of the reasons was also religion frankly because this the conventional wisdom in the in the Christian Church was that the sky was was not only God's creation but it was immovable and unchangeable and if you said you saw something new in the sky you'd likely be burned at the stake so it's not too surprising that it was never reported here but this was a nearby supernova but but interesting enough here's that supernova 1987 20 years later and you can begin to see a ring around and I think I'll expand it this is the material that's being thrown up by this star all the carbide the nitrogen and the oxygen the iron moving at about 10,000 kilometers per second and when stars explode they compress the gas around them and cause it to shine but they can also actually cause other stars to be created this is not a painting this is an actual image of a stellar nursery in our galaxy where after a supernova goes off it compresses the gas and other stars form and about five billion years ago a supernova went off in our region of the galaxy compressing the gas and causing our Sun what is now our Sun and solar system to eventually form 4.5 billion years ago and the material from that supernova not only made became part of the Sun but it eventually became part of the earth and all the other planets and every atom in your body as said in that video but it's true and it's the most poetic thing I know about the universe every atom in your body has been inside a star that exploded not just one star many stars because because in order to make up enough carbon and nitrogen oxygen lots of stars had to explode 200 million stars in our galaxy exploded before the thumb form and so the atoms in your in your body have been part and experienced the most violent thing in the universe and the atoms in your left hand could have come from a different star than your right hand but you were literally star children and I think that's a wonderful way to begin this because you have a connection an intimate connection to the cosmos it's not just out there it's in your bodies and your bodies provide us living histories of the history of the universe you like that okay folks you can applaud for that so I wanted so we are we are we come from the stars but I want to come a little closer and I want to talk about another connection that you have that you may not know about first of all this is a picture take it a nice sunset it looks like it's Los Angeles because the sky is red some used to be pollution but it's not that sunset happens have been taken on this place here in Mars the Mars is interesting to us because Mars is a dry planet now but it we think it originally had water as I'll show you and the ISTE question here is first of all we used to wonder where did the water on earth come from earth is a water planet but when the earth formed the temperature in the solar system in the region of the earth was about a thousand degrees so it was hard for for water to waters a volatile material and it turns out that most of if you work out we're being bombarded by comets asteroids meteorites every single day in one form or another and if you work out over the history of the earth enough material has been transported to the earth by comets to fill up all the words Earth's oceans so we thought for a long time that maybe that's where the water comes from but it there's a problem if you measure the content of the water in in comets and measure what's called the isotopic abundance the abundance of hydrogen and the next lightest or the heavy hydrogen called deuterium it's slightly different in the Comets than it is in the oceans on earth so we didn't quite know where the water came from maybe it was embedded in the earth originally to understand that we actually look at Mars because Mars unlike the earth doesn't have plate tectonics it doesn't it doesn't have volcanic activity most of the material on the surface the earth now wasn't always there because the earth is churning and that material goes inside and outside so there are very few very old rocks on earth but in Mars the material that's there has been there since essentially the formation the planet and if we could find water on Mars and measure its abundance we could learn about the water on earth but in the process of that we learned something interesting the question is where can you learn go to find rocks from Mars you don't have to go to Mars you go to a place that looks like Mars that's this place this is Antarctica the South Pole now why would you want to go to the South Pole to look for rocks from Mars anyone have an answer what I'm sure I'm getting lots of good answers but I can't hear them all but okay it's that the point is it's not very sophisticated notice that this is white okay and so it turns out material gets kicked out of Mars by meteors and comets and some of it falls to earth and some of it falls to earth here on this part of the planet but if you find a rock out there it's not very surprising but if you're in Antarctica and you are Nazca do I'm near the South Pole and you're going along the ice and you see a rock there's only one place it can come from up there so that's why we look for meteorites and Antarctica it's not because of anything sophisticated they're just easy to find anyone could do it I was going to go do it and if they wanted me to do it anyone can do it and interesting enough in this area the Allan Hills of Antarctica about 30 years ago this particular rock was found on the surface of the ice and it was ooh and it turned out to have the abundance have the right elemental abundance that we know it came from Mars and then it caused a great great furor about 20 years ago when it was cut into small pieces and put in an electron micrograph and when it would that was done these things were seen these small structures and President Clinton at the time had a press conference because these look just like the oldest fossils of life here on earth and it was our thought that maybe this was evidence of life on Mars now it turns out in the interim we've been able to show that that's not the case that these structures are actually much smaller than the earliest fossils of life on Earth scene gotten from Australia as it turns out and we and we think that you can create these kind of structures without biological systems but it but we've realized in the interim something very important all throughout the earth we found forms of life that exist in extreme environments they're called extremophiles and they can exist in boiling water and acid but interestingly enough those microbes can live in rocks for a long time even in dry and extreme environments that means that if there were microbes on Mars embedded in rocks they could easily survive the eight or nine month voyage through space so they got to the earth and that means that no planet is an island it means if there's life in one place in the solar system it's going to pollute the rest of the solar system at least all the accessible places in the solar system so the interesting question is this life evolved on earth and I can still use that word especially since we're not in the United States life evolved on earth about as soon as the laws of physics allowed about 500 million years after the year formed I'll have a ways to go anyway because before that we were being bombarded by comets and asteroids and the oceans were being evaporated but then Jupiter formed and basically ate up most of that material and things subsided but life formed on Earth extremely quickly and the question is that's a surprise to us how did life originate on earth we don't like know the answer although we're getting close but maybe it didn't originate in earth maybe it originated on Mars and was transported to her because early on and hit like in Mars it was hot and wet so if you want to know what a Martian looks like just look in the mirror perhaps now we don't know if that's the answer but interesting enough we've discovered as we've explored Mars and the surface of Mars evidence of with our Rovers which are a wonderful way to explore the planet in my opinion better than humans but we can talk about that but we've discovered evidence of even today water flows systems that look like there is actually liquid water today's still on Mars periodically and that's incredibly exciting because not only will be able to study that water but it gives us hope that maybe we'll find evidence of extinct or maybe extent life-forms on Mars but we don't have to go to Mars we can go to other the moons of Jupiter and Saturn this is a Enceladus a large block of ice which 20 years ago we just thought was a perfectly smooth white snowball but we've now discovered with the Cassini satellite the Cassini mission which explored Saturn Enceladus is a moon of Saturn that the ice isn't smooth at all and the fact there are water flumes and plumes that come up water volcanoes if you want because the gravitational pull of Saturn is enough to produce tidal forces that heat up inside Enceladus so Enceladus and IO are two ice moons that we now understand are not just dykes moons inside of them is a water ocean heated by the gravitational force of the big planets they're around and when when when the Cassini satellite flew through these detected would look like maybe organic materials and this material has been protected by a thick wall of ice maybe several kilometers thick and then there may be an ocean underneath it's a hundred kilometers deep and one of the exciting things we're going to do and maybe in the next two decades is send a mission to either E or Enceladus to maybe explore the surface and ultimately drill down and we may discover life here because all of the things that are important for life on Earth water organic materials and sunlight are prevalent not just here but everywhere in the universe we discovered organic materials the basis of amino acids on comets so it could be that we're not only not alone in the universe but we're not alone in the solar system now there aren't intelligent beings there but there could be microbes and if they're if there are life-forms inside of Enceladus those are exciting if we discover life on Mars that could be our cousins because we've been sending material back and forth by comets but if we discover life deep in the oceans of Enceladus that material has been protected and that could be another genesis of life and that would be very exciting because we find two independent genesis of life in the in the in our own solar system it means it's everywhere in the universe but ultimately we are connected in one way or another to life in our solar system so we are not just if we discover life on mars as i say it's our cousin so we're not just connected to the stars we're connected to the other planets and we could be martians so that's the next cosmic connection i want to make so we're connected to the stars we're connected to a potentially life on other planets but we're connected to each other in a way that you wouldn't maybe not imagine I wouldn't do an experiment everyone I want everyone to take a deep breath and then hold it in okay one two three take a deep breath hold it in you can't laugh while you're taking a deep breath keep holding it keep holding it okay let it out there was no reason for that I just wanted to see if you do it but but there sort of is every time you breathe in your being connected to all of humanity and throughout history who's this does anyone know this is Julius Caesar that's right the amazing thing is and it's one of the things I love to teach in an undergraduate physics class every time you take a breath you're breathing in atoms from the dying breath of Julius Caesar when he said ed to Brutus every single time you breathe you're breathing in atoms from Julius Caesar's dying breath it's amazing but it's true his atoms of his breath were circulated throughout the atmosphere and because of the processes that circulate things through the earth and the atmosphere and life we can actually calculate that maybe 10 or 20 atoms of his dying breath are in each of your breaths but that means not just fuel your Caesar but that means everyone throughout human history people we think of as scary as others are part of us they're not just others they're part of our bodies right now okay good this is a great this is clearly resonates with people who are stoned okay anyway but this is useful think of that think of this the next time you breathe in but I mean I use it all the time I spend a lot of my time I try when I can work which is increasingly rarely mostly on planes but if I'm alone at night and I'm working and I'm not getting anything done which is also usual I remember that each time I breathe in I'm breathing in some atoms that Einstein breathed out when he put the final dot on his general theory of relativity so this is wonderful you are breathing in atoms from virtually almost everyone who ever lived the good people and the bad people you're real to breeding in atoms from Hitler when you put the last note on what mine calm okay and speaking of what my mum said well I guess I can say this inner so when you drink a glass of water or alcohol you're drinking in atoms excreted by every slimy thing that's ever walked the earth in particular and this is really interesting for some of you if you have water take a drink right now or even alcohol take a drink right now every time you drink a glass of water you're drinking and in atoms from the sweat of your parents during their coupling that created you okay I remember the American comedian WC Fields I never said this before on a stage but this place it seems ok I remember WC Fields used to say about water he said water I never drink it fish fucking it and and now you know it's true you're drinking it when you come in and every time here's the yacht's younger me this is Lucy who was a wonderful ancestor of ours 3.2 million years ago after Australopithecus Lucy who we found and every time I breathing in not breathing in atoms at Lucy breathe out but it's not just Lucy these are stromatolite these are these are these are the earliest this is from Shark Bay Australia which you can see here these are fossil remnants of the earliest organisms that produced oxygen on earth the cyanobacteria that originally originally there was no oxygen in the atmosphere the earth all the oxygen you breathe all the oxygen you breathe was produced by the early organisms on life on Earth that's one of the reasons why when we look for life on other planets we're going to look for oxygen atmospheres which isn't a guarantee of other life but I'd be a strong signal because it's important for life history of life on earth that there was no free oxygen because oxygen is a poison it burns things and if there had been all the organic materials on earth would have been oxidized early on but they weren't the life created the oxygen every way so these things puffed out little bits of oxygen and over two billion years in the early history of life on earth the oxygen abundance built up until life figured out how to use oxygen by respiration so every time you breathe in you're not just breathing in battles from Julius Caesar and and and everyone else but also the atoms breathe out by the stromatolite over two billion years you're connected to everything that's ever lived on earth your connectr the Stars the planets and everything that's ever lived on earth okay and in fact when I talk about this about your what you what you're drinking when you drink in here's another experiment you can do take your finger and prick trick it and take a little bit of blood and go out to the ocean and let it drop of your blood go in the ocean interestingly enough if you come back a year later and take a spoonful of ocean water we'll be some atoms of your blood in it it gets distributed throughout the whole ocean you are literate Kenton so this is a quote from Shakespeare that you remember in Macbeth when they killed a king and he says will all great Neptune's ocean wash this blood clean from my hand no this my hand will rather the multitudinous seas incarnadine in english that means that that i'll turn the book ocean's red there's too much blood on my hands and of course it's true every time you bleed if it goes in the oceans you'll turn the oceans red in a very small way so those connections to everything on earth are remarkable and and totally unexpected I think and I hope that gives you a different perspective of your place but I want to point out now I want to talk about a different set of connections the kind of connections that relate you to things that are esoteric the kind of physics I do is very esoteric and people say what good is it and and and does it make a better toaster or a faster car it doesn't but it does help and I first began to think of this when I was stuck in in Los Angeles but the same could be said for coming here so I can I flew in at about 11 o'clock today from the United States and I came from the airport to - well that's the hotel I'm in but you shouldn't know that anyway and except for the beautiful women they should all know that now but anyway um no and so I one uses GPS then the good-looking guys - I guess no I'm just joking anyway um that's the problem of drinking before speaking it's really a mistake but and the point is every time you use your GPS you're using you're relying on remarkably esoteric laws of physics that you may not know so how does GPS work GPS works because there is a network of satellites around the earth and we use triangulation so these satellites are way above the earth and what we do is if is when in when your transmitter is detected by two different satellites those satellites calculate the time that it takes for the signal to go from the saddle lights of the earth and back and from that they can determine the distance to where you are and we have two of them or three of them or four of them they can pinpoint your position sorry and that's why we use we need to have several satellites in view in order to use GPS okay so those two satellites measure your relative the time it takes to get from there to there and back and and then very carefully but they have to have very accurate clocks to measure your position very accurately because light goes about one meter every billionth of a second so if I want to know your position to 10 meters accuracy say then I have to have a clock clocks on those satellites that are accurate to 10 billions of a second atomic clocks can achieve that kind of accuracy but we have to recognize that these satellites are out there so light travels of 30 nanometers per 30 centimeters per nanosecond that's 30 centimeters every billion to the second now these satellites are up and I'm going to use American units here I'm sorry but eight thousand twelve thousand miles above the earth most of them and they're traveling around the earth at 8,000 miles per hour and this means that esoteric laws of physics matter so to get accuracy of five ten to five 10 meters 20 to 30 nano second accuracy now relativity tells us that if I'm moving with respect to you my clock is thinking slowly with respect to you this is not observable on earth most of the time but if I want to measure things with accuracy of nanoseconds and things are moving in a thousand miles per hour I have to use this and in fact special relativity that tells me that the ratio of the time of two clocks depends upon this which is where this is the speed of the of the clock and this is the speed of light normally because we move very small slowly compared to the speed of light this is irrelevant but in this case it isn't it turns out that these clocks because they're moving on the earth very fast tick at a rate of seven microseconds per day more slowly than clocks on earth but this isn't the only effect Einstein also told us that if I'm standing up here my clock is ticking at a different rate than your clock because being at a different place in a gravitational field also means clock it clocks tick at different rates and these clocks are up at 12,000 miles above the earth so general relativity tells me if you plug things in that in fact because these clocks are this high they're ticking it turns out 45 microseconds per day faster than clocks on earth now this means that they go in different directions that these clocks are ticking relative to each other and relative to clocks on earth at a time difference of 38 microseconds per day but 38 microseconds is 38,000 nanoseconds and that means if the makers of GPS didn't include the facts of the curvature of space and the effects of special relativity things you'd never think you need to ever think about then your GPS would lose accuracy in two minutes in two minutes you'd be out by about a kilometer and so every day in order to get here or anywhere you go in your cars and use GPS you're relying on the fact that space is curved this esoteric result from general relativity that is remarkable so even if the most exotic aspects of physics creep in and change our everyday lives now this isn't this this this is meant to hypnotize you take a drink while you're doing it this hidden connection the fact that you're connected to a curved universe is even more it's something that that we're using in physics nowadays in a different way not only is space curved not only are clocks on these satellites taking a different rate not only is my clock here ticking at a different rate than yours there but every time I move around the stage I'm disturbing space because Einstein told us that space and time respond to the presence of matter and energy and when I move around and wave my arms like I often do I'm producing a curvature of space that's varying in time and in 1916 Einstein realized when he wrote down general relativity that when I do this I'm producing a moving disturbance and it causes a ripple in space when I shake my electric charge up and down I produced a disturbance and electric and magnetic fields that is responsible for everything in this room the lights I see those come from that kind of shaking electromagnetic waves result when I shake charges up and down and the electromagnet is light that's how I see but Einstein showed us if I shake am ass up and down I disturbed space I produce a disturbance and curvature in space and just like a ripple on a pond that that disturbance travels out in this case at the speed of light and what it means is every time I do this I'm actually changing the space in this room and every and I'm producing what we now call a gravitational wave and that means and there are tons of gravitational waves going through this room right now and when a gravitational wave goes through this room it much as if it went through this screen the length of the room gets smaller in that direction and larger in that direction and then smaller in that direction and larger in that direction and that's happening now those of you who've drunk a few of these notices right away but it effect is so small that we don't notice it why don't we notice it because gravity is the weakest force in nature it's hard to believe that gravity is so weak because we when you get up out of bed in the morning you feel it right away but that's all the atoms of the earth affecting a single atom in your body but gravity is the weakest force and and Richard Fineman gave an experiment to show how gret weak gravity is take a friend maybe not a friend to the top of a high building push them off it takes all of the atoms in the earth and their gravitational force to pull them all the way to the ground and maybe a hundred meters if it's a really high building but electromagnetism stops them in a fraction of an inch they don't even make a dent in the concrete because the reason I don't fall through this stage is not that it's solid it's mostly empty space but the electric forces of the electrons in my hand or in this case my feet are repelled by the electric forces of the electrons in the in the stage so just the electrical forces of the electrons in this stage are holding me up against the entire pull of the earth gravity is so very weak and that means the gravitational waves I create are so small you'd never be able to see them here's a three-dimensional gravitational wave moving through which looks nice but it doesn't have any information but those 3d images don't but the point is if this is there we'd like to be able to detect it if these ripples in space are occurring all the time are they really happening or is this a figment of our imagination and what amazes me is that we have built the most amazing machines to be able to detect these ripples in space here's the here is a machine the largest gravitational wave detector in the world the LIGO the laser interferometric gravitational wave observatory there's two copies of this this is in Hanford Washington there's another one in Livingston Louisiana exactly the same and what these things are are two arms two perpendicular arms each four kilometers long and if a gravitational wave comes down from above what will happen is the length of this arm will get a little bit smaller and the length of an arm will get a bit longer and then the length and that's then the length of this one will get smaller and that will be longer so all you have to do is measure the length of these two arms very carefully simple not so simple gravity is so weak that we calculate if the most cataclysmic we can imagine happening in the universe today the collision of two black holes solar mass black holes happening in our galaxy or some distant galaxies happen to massive objects more massive than our Sun colliding well they'll produce a lot of gravitational waves it gives the more intense the gravitational field around the object and the more catastrophic the event the bigger the gravitational wave signal so we can look for two colliding black holes solar mass black holes but the effect is still very small in fact we can calculate that if two black holes collide in a distant galaxy two solar mass black holes gravitational waves will be produced and they'll change the length of this arm relative to that arm fine amount we can calculate these alarms are four kilometers long and in order to be able to detect this signal we have to detect the fact that these gravitational waves will change the length of this arm four kilometers long compared to the length of this arm by an amount equal to one one thousandth the size of a proton now that should amaze you one one-thousandth the size of a proton what's even more amazing is we can do it we can do it and then I'm not an experimentalist and this is one of the reasons why because I never would have figured you could do this and in fact it's really hard to imagine that you can do it because if a truck hits a pothole over here it produces a bigger signal here so how can you how can you get rid of that while you build two detectors one in Washington or one Louisiana and if a patient wave traveling at the speed of light hits this detector and goes through the earth eight milliseconds later it'll go through the detector in Louisiana so what you look for is a signal in this detector and exactly the same signal eight milliseconds later in Louisiana and in September 15th I think 2015 we saw the first gravitational wave ever discovered in the universe this is this is the signal and it's a signal of two black holes colliding in a galaxy 1.3 billion light-years away causing space to ripple and vibrate back and forth it turns out with a frequency of about 300 cycles per second that means these two objects these two solar mass black holes one was 36 times the mass of the Sun the other is 29 times the mass of Sun they were orbiting each other a hundred times a second before they climb - think about that - solar mass objects orbiting each other a hundred times a second and what's amazing is not just that we can detect the signal but we needed not just the most sophisticated technology available on earth because even the quantum mechanical motions of the mirrors are bigger than one one thousandth of a size of proton so we have to use what's called quantum optics to overcome that but we have to use the most sophisticated theory we can do because if you see a random bit of noise how do you know it's colliding black holes you have to have a expected signal to compare it to and the mathematics of general relativity is very complicated and we needed supercomputers and over the last 20 years we needed those supercomputers only of two years ago did we have the technology in the experiment in the theory and so this template sort of smoother line is the template of what you'd expect if two black holes collided and we can compare the signal to the template and we see it's a beautiful thing and this was the signal seen in hanford eight milliseconds later this was a signal Tina in Livingston and the to fit exactly on top of one another and what we saw was a signal of two black holes colliding 1.3 billion light-years away and I'll show you the animation of this it says not the visual this is an artist's simulation but you can see when these black holes are moving around they're bending the space around them and they're causing the light around them to be perturbed so you're actually the stars behind them look like they're moving because the space is curving and this is a slowdown of the actual last two tenths of a second in the life of this two black holes as they collide and merge to form a single black hole and you watch in the last moment you'll see space jiggle and that's the generation of gravitational waves there see it jiggle now that's a signal we saw now the amazing thing there's two amazing things about this first that we saw but secondly it was a it was a 36 solar mass black hole and a 20 million solar mass black hole and they combined together to form one single black hole how massive was that 36 plus 29 36 plus 29 anybody who said 65 put up your hands you said 65 put up your hands knows more than just you okay you said 65 wrong because it's amazing it turns out they form the black hole of 62 times the mass of the Sun three solar masses disappeared where did those three solar masses go to into gravitational waves now that may not amaze you but it should because our Sun is burning a hundred billion hydrogen bombs every second to produce the light that we see and over the it's turning mass and energy e equals MC squared over the 10 billion light year lifetime of the Sun less than 1% of the mass of the Sun will turn from matter to energy in two-tenths of a second these objects turn three times the mass of the Sun into energy that meant stirring that two-tenths of a second that object emitted more energy than all the rest of the stars in the visible universe combined it's amazing that these things happen and we detected it now as amazing as that as these are interesting gravitational waves but the gravitational waves that are interest to me are going to be looked at by different machine this is at the South Pole we're looking for gravitational waves not from the collision of two black holes but gravitational waves that connect us to the beginning of time we think we're here because an event that happened when the universe was a millionth of a billionth of a billionth of a billionth of a second old when our universe expanded by a huge amount you know someone's trying to call me right now hold on let me just stop that okay we think at that time in universe was a millionth of a billionth of a billionth of a billionth of a second old our universe expanded by huge amount puffed-up from the size of a single atom to the size of a basketball or soccer ball if you're here in Europe in a short instant now if two black holes colliding produce gravitational waves if our entire universe expands like that it'll produce gravitational waves that are that are we hope we'll be able to detect one day and this is the machine we're hoping to use to detect them among others this is called the bicep detector it turns out that these leave and imprints these gravitational waves we think leave an imprint in the microwave background radiation that's coming at us from the Big Bang that's coming at us from all directions that we measured first 30 years ago and I've now seen more seriously in various other ways when we look out we see this radiation coming at us from all directions we call it the cosmic microwave background radiation that was emitted when the universe was about 300,000 years old which is when it became transparent to radiation and we look out we have pictures of the universe back at that time but embedded in those pictures may be a signal of gravitational waves that have come at us from the beginning of time and these kind of detectives we're looking for them it turns out these detectors are the South Pole they it's not cold enough at the South Pole to use them we have to send down liquid helium to use these detectors because it's not cold enough we send down that liquid helium in the summertime does anyone know why when when it's winter and Antarctic it turns out you can't send planes down there isn't that amazing I when I first learned that I was shocked we don't send planes dance act our arctor in the wintertime I mean we can go to the moon well that was faked but we can go down to the depths of the ocean we can go ever but we don't send planes Antarctic in the wintertime that's why this is one of my favorite images this is from the bicep detector and it's sub sunset something happens once a year at the South Pole so it means if you take this picture you're stuck there for the winter okay just why this picture was taken by a graduate student okay but it turns out that this detector and others like it that are being built may allow us to detect gravitational waves from the moment of creation which connecting us to the process of produced ultimately all the stars and galaxies we see today a process we call inflation and what's really kind of interesting is that we think that this process that caused our universe to explode in size actually caused space to continue to explode in most other places our universe basically was like a seed that condensed out of this rapidly expanding universe but that expansion continues even today and that means there may be other universes being created right now as other seeds collapsed on without a background expansion and inflation happens then our universe isn't unique there are many universes out there and it turns out when you leave inflation the laws of physics may change depending upon how you leave inflation and that means some universes may form with a lot of galaxies some universes may form with no galaxies some universes may form with just the right number of galaxies so it could be that all of the physics the properties of our universe are just one big cosmic accident that if that in a different universe with the laws of physics would be different we wouldn't be here that makes it sound like the universe well it basically says the properties of the universe are are the way they are because there are astronomers here to measure them that sounds religious but it's not it's cosmic natural selection because it says that our universe is one in which we could evolve it'd be fascinating to find ourselves living in the universe in which we couldn't evolve that would be a worth a book or two but but no one be around to read it and this idea of what's called a multiverse when I first wrote a universe from nothing five years ago was just a pure speculation based well-motivated speculation unlike God but one that was pure speculation metaphysics if you wish but what I find amazing is we're on the threshold of potentially being able to measure gravitational waves from inflation which if we could measure them would tell us about that inflation happened would allow us to probe that theory and see if indeed other universes are being created not we wouldn't be able to see them directly but we'd be able to test the physics that created our universe and know indirectly that those other universes are there just like over a hundred years ago we knew atoms existed but we never thought we'd see them if this is true we'll turn metaphysics into physics will know indirectly that these other universes exist and that we're not only not alone in our universe but that our universe is not unique and it amazes me to think that in my lifetime we may believe and know that where our universe isn't unique that we are in a sense connected not just to other all the stars in our universe in any way but to other universes by that act of inflation now this cosmic accident is similar I want to end with another cosmic accident which is related to my new book in more detail the greatest driver told so far relates to a fact that we are all here by another cosmic accident there's a bathhouse here and I wanted to go to it but it's going to be closed now so I can't but let's say you're swimming in water and you swim very fast fine let's say I filled that swimming pool with molasses well you wouldn't want to get in first of all but if you did go in and you tried to swim you'd swim much more slowly because the molasses would produce much greater resistance well it turns out that we think that that's why we're here that is an invisible field everywhere throughout our universe that froze in the early history of our universe and some of the particles in nature interact with that field so as they move along they experience resistance and they act more massive those particles interact more strongly with that field or more massive those are particles that interact less strongly with that miel field are less massive and those that don't interact with the field at all are massless light doesn't interact with that field but at a fundamental level all the particles that make us up are really massless they act like they have a mass because that field is there now that sure sounds like religion right because what I said was there's an invisible field everywhere in the universe and it's reason we're here and that would be religion but it's not religion because we can detect it or we can try and detect it how do we try and detect it perfectly in keeping with the video at the beginning of this program cosmic sadomasochism we spanked the vacuum we spanked it hard because it turns out in quantum physics if for every field in nature is associated with a particle and if we take enough energy and dump it into empty space in a single place we'll will take that field and we'll kick real particles out of it and if we call that field the Higgs field and we kick real particles out over we'll call them Higgs particles so where can we dump enough energy and empty space in a single point to kick out Higgs particles how can you do that you create the most complicated machine ever built the Large Hadron Collider in Geneva Switzerland you go to Geneva and there's the lake the fountain is over here if you land at the airport which is right here which I did a little while ago you look out and you see just countryside beautiful countryside but underneath the countryside is a tunnel 26 kilometers around and in that tunnel we accelerate particles at 99.999999 98 percent the speed of light in that direction and particles at 99.999999 9 8 percent the speed of light in that direction and we try and collide them two places this is the French Swiss border right here they go around thousands of times every second without passports don't tell Donald Trump will be upset but we then try and collide them in and in fact July 4th is a big day in the United States for no real reason but in no cosmic reason anyway but July 4th now has a cosmic reason for celebrating because of July 4th 2012 the Large Hadron Collider reported 50 events that walked like Higgs ah's and quack like Higgs is and therefore we thought were Higgs particles and in fact in the intervening 5 years all the data has told us that they have exactly the properties of Higgs particles we discovered that there's an invisible field in the universe and that this amazing story that we're here because of that invisible field is really true I mean it was so amazing that I was certain it was wrong I'd written three papers which I had in my drawer waiting for it not to be discovered so I could show it was wrong because I thought nature would find another way to do it it seemed kind of slimy to have this invisible field everywhere but that's exactly the kind of invisible field that could have produced inflation so it gives us further motivation to think that inflation happen but that means that we are here by a truly cosmic accident if you look at in the winter time in a window and look at the icicles on a window say save this icicle here imagine that you were a civilization that evolved on that icicle that grew up to that icicle to be physicist and they discovered the laws of physics are different along the spine of the icicle then along the perpendicular direction and they described those laws theologians would explain why that direction was special why it was meant by God Wars will be fought over whether it was that direction or that direction all of this would take on incredible significance but seen from the outside we see it's just an accident icicles can form in all different directions it's just an accident our existence here in the universe is the same kind of accident if this Higgs field hadn't frozen the way it did in the early history of the universe and had frozen in a different direction the forces and the laws of physics we feel would be different and in fact we wouldn't exist but imagine that physicists on this ice crystal figure out that you know there's nothing special about this direction that all the sorts of different directions could exist and they figure it out at 4:00 in the morning and it's 6:00 in the morning the Sun rises and the ice crystals melt and they go away that could be us because we've discovered the Higgs field but we've also discovered given the properties of that field we've measured it could be unstable it could melt in the future and if it melts in the future then all the particles that now have masks will become massless again and that means no structures will exist all the stars and galaxies and everything that we feel connected to will disappear and that could be our future don't look get too nervous don't sell your diamonds because even if this were to happen and we're not sure what happened it won't happen in a year or in a decade or in a million years or a billion years or a billion billion years it'll happen in the far future but in the far future the universe could return to the state it was originally in one that was not in which life as we now see it was not possible so those people think the universe is designed for us it's no more design for us than that direction is significant we are a cosmic accident and that's okay that's remarkable we should feel thankful the universe doesn't isn't any more designed for us than it was designed for that crystal to exist in that direction this idea of understanding that the universe is not necessarily the way we wanted it to be its humanity and its best one of the wonderful things about being here besides being with all of you and in this amazing venue is this connection between art and music and science that's happening right here tonight because that's the beauty of science it's not the technology I mean science creates technology but I almost think of it as an unfortunate thing because the real beauty of science is the same as the beauty of art music and literature what science does is change our perspective of our place in the cosmos change our understanding of ourselves that's what we get when we read a good play or see a piece of art or hear a new piece of music it's forces us to reflect on ourselves in a new way that's the beauty and the force our beliefs to conform to the evidence of reality instead of the other way around is wonderful to take cherished beliefs and prove them wrong is wonderful because it means we're learning and that's what makes civilization worth being called civilization the fact that the universe isn't designed for us has a long history and I want to end by just going back to the person who first showed in the context of life that the universe wasn't designed for us Charles Darwin so one of the most beautiful bits of science writing in all of science writing history is the last paragraph of his origin of a species that reads as follows there is grandeur in this view of life with its several powers having been originally breathed into a few forms or into one and that what this planet has gone cycling on according to the fixed law of gravity from so simple a beginning endless forms most beautiful and most wonderful have been and are being evolved in that beautiful way he showed how from a simple beginning the incredible diversity of life on earth could arise not by planning but by natural selection bees aren't designed to see the colours of flowers if they didn't see the colours of flowers they couldn't reproduce they couldn't get the nectar and reproduce it's so simple to see something that looks like it's designed the appearance of design can be an illusion and not just as it's true for life we now see that the even for the universe the appearance of design is an illusion just get over it and but at the same time science changes and scientists themselves are myopic and in 1863 he said in a letter to Joseph Hooker it is mere rubbish thinking at present of the origin of life one might as well think of the origin of matter now in 1863 that was garbage but I get paid to do it now because things have changed because the greatest story ever told has gotten better because we keep opening our eyes to the universe we keep getting surprised by the universe and we'll keep on getting surprised by the universe and being human will continue to be more interesting but only if we keep our eyes open only if we're willing to keep asking questions and stop if we stop asking questions if we're afraid of what we'll learn if we're afraid of others all of that will stop and while it's an issue in my country I think it's an issue more generally I am concerned in the current world about this fear of the unknown of this fear of others about this fear of what science may tell us and that people would rather bury their heads in the sand and not support not just science but art music and literature and the response to that is the best response to that I know is by this guy Robert Wilson who is the first director of the first large accelerator in the United States the first really big accelerator the Fermi National Accelerator Laboratory in the 1960s he was asked by Congress will that accelerator aid in the defense of the nation and he said no sir I don't believe so it is only to do with respect with what you regard one another the dignity of men our love of culture it has to do with our Weaver good painters good sculptors great poets I mean all the things we really venerate in our country and our patriotic about or should it has nothing to do directly with defending our country except to make it worth defending and that you can applaud to that because we've dead now but it's a wonderful audience that is why that is why we can't afford to stop supporting curiosity-driven science research we can't afford to stop supporting art music and literature my country the current budget there's huge cuts in all of that and the money is going to build a wall to keep us out from invisible hordes but what makes the United States make great let's make Denmark great what makes the world worth living in is not the walls we build are the arms we sell but the questions we ask and our willingness to keep open eyes and look at the universe so the universe may be miserable the universe we may be insignificant but we shouldn't be depressed because those connections that we've made to the cosmos tell us about it amazing accident that brought us here today nevertheless it allowed us to evolve brains that can ask questions that can turn and ask questions about the early beginnings of the universe and look out to the farthest elements of the cosmos so instead of being depressed you should enjoy your brief moment in the Sun thank you very much thank you

Channel: Science & Cocktails

Views: 64,674

Rating: 4.7536535 out of 5

Keywords: Science and Cocktails, science&cocktails, Copenhagen, Christiania, science talks, science communication, science popularization, science lectures, science conference, ecsj2017, Lawrence Krauss, cosmology, theoretical physics, School of Earth and Space Exploration, Space, Cosmos, Origins Project, Arizona State University, science education, does God exist, is there a God, God, atom, Universe, the big bang, Earth, A Universe from Nothing, black hole, yt:cc=on

Id: XIzJMTPvCEk

Length: 65min 26sec (3926 seconds)

Published: Mon Jul 10 2017