welcome to the Big Bang class of 2013 it's great to have you here professor Cox it's great to have all of you students from riding here it's great to have all you folks who are watching online right at the moment the Big Bang class of 2013 is part of the same program as the Big Bang Fair which is taking place at excel in London it is in fact one of the biggest celebrations of science math engineering and technology for all young people in Britain it takes place at the excel on the 14th to 17th of March tickets are free and you can book them online at the Big Bang fair co uk Professor Brian Cox teach lectures at the University of Manchester he also is a particle physicist who works at CERN in Geneva where the big back where the big hadron collider is so professor Bryan Potts without further ado very welcome to ryan Community College thank you thank you and I should say congratulations I know you entered the competition I'm delighted to be a fantastic music and I just wandered around your labs which I also thought were wonderful I spoke to a lot of you I should say how many of you are thinking of being scientists at some level quite a lot of you I mean there I I want to talk really about I've got to stand in a particular place actually they told me so that the camera can see me so I usually wandered around understand here I want to just I will talk about strana me of course because that was my my first love it was really the thing that inspired me to become a scientist I always thought I was going to be an astronomer but I thought I'd start with a couple of pictures I've got a series on the BBC at the moment called wonders of life which really was an introduction to me or a reintroduction into biology and I was surprised how much as a science biology had moved on since I studied actually back in 1980s sometime so probably when your parents studying biology and I thought I'd show you a couple of photographs of some of the strange animals and the interesting thing for me about biology from a physicists perspective was learning about how those animals came to be the way they are because as you know you only have to look outside now we live on a planet that is absolutely covered in different forms of life or of course human beings which are the most complex things we know of in the universe but there's also trees and there are blades of grass and there are birds and then there are things like this have you ever seen one of these things before you've seen do you know what it's called yes sir it said does anyone know what this thing's called an aye-aye that's it it's a kind it's a lemur which is a kind of a primate so in some senses it's quite closely related to us and monkeys and gorillas but this thing is very unusual because of this oh you can see there that long spidery fingers I've got another picture of the aye-aye here admire look at that it's one of the strangest things look at those fingers there now the question is why why does this think I fingers I've seen the film at UT and there's a question so what about over there what do you know why it's got those fingers anyone there that that's right did the answer is that it uses it it's like a woodpecker so this animal it lives in Madagascar there are no woodpeckers in Madagascar but there's food in the trunks of trees so what the aye-aye does it he gets this middle finger out which is twice as long as its other fingers and it taps on the tree bark and it listens until it hears a hollow sound when it hears a hollow sound it gnaws through the wood with those bizarre teeth which are actually teeth like a rodents teeth they continually grow which is different to other primates and when they burrowed into the bark they get that long finger out again stick it in the bark and get the grub what is the answer to that how can he be the something is so perfectly tuned to its environment well the answer is evolution the answer is that over millions of years and we think actually that the lemurs of Madagascar have been isolated from other the other primates that live in Africa the 60 million years or more and some changes little changes in their DNA caused at some point one of these are the ancestors of these animals to get a very slightly longer finger and that would have given it a slight advantage in might have meant that it could access a bit of food other lemurs couldn't have which means it was more likely to have children and those children would have had the gene that had the slightly longer finger and over time over thousands and tens of thousands and millions of years you get this animal that's bizarre and perfectly adapted to go and live in the trees in the forest Madagascar a strange animal indeed here's another example that I thought you might find fascinating this is the largest land crab in the world and you see that these things climb trees why have you ever seen a crap the size of that before the reason is they live on just a few islands and one in particular called Christmas Island which is part of Australia although it's right up near the coast of Indonesia it's a tiny little place and and on that place there are no predators at all there are no big mammals there are no cats there are no there are no dogs or any kind of animals like that so the crabs have become dominant on the island and so the biggest crab which is the biggest predator on the island has been able to get bigger and bigger and bigger and these things are quite intelligent and actually when I was filming with one of these things he went into my bag which I'd left down and stole money out of my bag and ran off so they're also they're called robber crabs or coconut crabs because they do this and actually I heard a story of a girl on the island who apparently had one as a pet and put it on the lead and dressed it up in clothing like a little doll so very strange animal indeed I just wanna flip through these if you watch my program the other night you would have seen me hold this thing it's called a catfish its evolved in a very different way it's a predator that lives in dark silty rivers actually in the Mississippi in the United States and it size and no use because the rivers full of silt so what it's done is its evolved its sense of touch and smell and in fact the whole of the fish is essentially a giant tongue and it can taste tastes with such precision that it can map out where its prey is in the river just by sensing chemicals across its whole body and that's how it hunts and finally for no reason at all I thought I'd show you in acting which is actually going to in the program this Sunday I think it's a three-month-old lion cub beautiful thing the interesting thing from the line clubs well the reason we film the lion cub is because although it looks quite different to me it is extremely similar in many ways and indeed its eyes are almost identical to ours it uses the same chemicals in its eyes and in fact as you look across the whole animal kingdom even to animals as bizarre as an octopus or a catfish or even insects then at the basic level their eyes work in the same way as ours so beautiful little lion cub by the time they're 12 months old they're too big and too dangerous to go near essentially so you can only touch them and Stroke them when they're about 2 or 3 months and then they soon get into fully grown lions so the question for a scientist and is really those things are beautiful we can look at them we can classify them we can understand how they behave but the question particularly fer for physicists and biologists are interested in the fundamentals of life is how how how was it how did it come to be the earth is populated by so many wonderfully diverse organisms and from a physicists perspective you want to go back all the way to the beginning so this is a picture of the origin and evolution of the universe as we know it now now we made a spectacularly precise measurements of the age of the universe recently actually the current number is thirteen point seven five billion years old there's got decimal points off after it plus or minus not point 1 billion years actually so there's even errors I know when you if you're doing your experiments in the science lab then you're encouraged to see what is the error on this measurement if I can measure some Finnish 3 centimeters long is there an error of a millimeter or so in that measurement well we've measured the age of the universe with errors to thirteen point seven five billion years tremendous achievement so the picture is that thirteen point seven five billion years ago the universe began why we don't know we don't know the answer to questions such as what happened before the Big Bang I get asked that a lot the answer is we don't know it's out there it's current research but we do know that the universe was extremely hot and extremely dense and extremely small thirteen point seven five billion years ago in fact everything we can see in the universe today we think at some point was compressed into something smaller than this room and actually probably smaller than your head and in fact probably smaller than an atom and I'm going to show you in a minute how big the universe is at the moment so it's a tremendous thought but what we know is the universe expanded and cooled ever since and as it cooled complex things began to well initially crystallize out I want to tell you about one of those complex things in a minute but it's a strange thought that we know fairly well at the moment and this is one of the things that you can learn as you go on in science to GCSE and a-level l2 university is just how precisely we understand how things began to crystallize out and just from that ball of energy thirteen point seven five billion years ago we get today things like DNA and planets and stars and people how do you go about finding out one way is to look up at the stars the other way is to build machines that can explore the universe by recreating the conditions that were present close to the Big Bang I'll show you one of those in a minute but I mentioned that I just say just show you how big the universe is and this is the best way I know of doing it so this is a picture of a piece of the night sky so there's the moon so it's clear tonight it might be clear tonight you go you look at a full moon then it's that big there's a piece of sky which is that big relative to the full moon so a tiny piece of sky it's actually another way of thinking about is if you get a five pence piece and hold it up just about arm's length perhaps a bit further away then you'd cover a tiny piece of the sky and a picture has been taken of that tiny bit of sky so the tiniest five pence piece covering up a little piece of sky it's called the Hubble Deep Field image it was taken by the Hubble Space Telescope which is in orbit around the Earth and I'm going to zoom in on that piece of sky so that's actually the constellation of Orion if you know if you know a bit of astronomy you go and see Orion in the winter sky so we're going to zoom into the piece of sky and this is the most detailed picture ever taken of our night sky of our universe it was taken from the Hubble telescope in orbit around the earth it was taken over thousands and thousands and thousands of seconds so the Hubble kept going round kept taking a picture so you get more and more detail and this is the picture it's called the Hubble Deep Field image now that piece of sky was empty as far as we could tell from the surface of the earth so imagine look into the by kist most boring piece of sky you can that's what it looks like when you take a very detailed picture of it and you see that it's not empty at all in fact every point of light in that picture other than about two or three a galaxies they're not stars there are about three stars in our galaxy in this picture the rest of them are other galaxies and I think about what a galaxy is they're Islands of a hundred thousand million stars or more billions of stars in fact our nearby galaxies the nearest one called Andromeda which you can see if you go somewhere dark on a very clear night you can just about see with the naked eye as perhaps got a trillion stars in it imagine that a trillion Suns so each one of those point you can see some of them you can see that there they're not blobs they're little spirals and these are galaxies there are over 10,000 and of them in this picture that's that piece of that five pens please bit of sky 10,000 when you extend that over the entire sky there are hundreds of millions of galaxies in the observable universe the most distant ones in this image by the way are some of the most distant objects ever seen so light travels that what 186,000 miles a second so what's that 300,000 kilometres per second 300,000 kilometers per second is taken over 13 billion years for some of the lights from these to reach us third can you imagine at 13,000 million years driving at 300,000 kilometres per second so they're a long way away so the universe what I'm trying to tell you is very big indeed billions of galaxies trillions and trillions of stars and as I said what we now understand is that some point 13.7 billion years ago all that was compressed into something much smaller than this room incredible discovery so it expanded and cooled and got more complex how do we know what happened how do we know how it started and how it was billionth of a second after it began where we can build experiments just like the experiments I saw in your science lab to do it this is the one that I work on which I'm sure many of you I should ask you do you know what this is called who knows what this is yeah it's CERN it's the Large Hadron Collider this is the biggest scientific experiment ever built and the red circle there this is drawn on a picture of essentially France with a bit of Switzerland at the top the border is somewhere around there if any of you've ever been lucky enough to go skiing in France you might have flown into Geneva you might have landed at that runway that's an airport just to get some sense besides of this experiment it's written all in red because it's Underground so you can't see it from the air it's about 100 meters on the ground and it's a big tunnel 27 kilometers in circumference it's job is to take protons which of which you're made they're building blocks of atomic nuclei the building blocks of take single protons and he accelerates them to 99.99999 99.999999% the speed of light incredibly fast they go round there 11,000 times a second when they go in at full speed and his job is to smash them together so it takes one lot of protons and sends them that way around very fast the other set around that way and smashes them together in those collisions you recreate the conditions that were present around a billionth of a second after the universe began just for an instant and our job as physicist is to take pictures of those collisions and it's like going a time machine it's variously once again a time machine sending it back to the start of the universe and taking a picture of what it was like by the way I don't wanna give you too many numbers but we can make 600 million of those collisions every second 600 million collisions every second bang bang bang bang for little Big Bang's remarkable achievement and we've taken pictures of them we take pictures of them using cameras as you would but they're big cameras this is a picture of the camera that I work on it's called Atlas and I just want to show you can you see that there that's a person right stood next to the camera and there's another one there so this thing it wouldn't fit in this room you see the numbers it means anything at all it's 44 meters wide 22 meters in diameter and it weighs 7,000 tons but it really is a digital camera those little mini big bangs happen right in the middle and this thing takes pictures millions of pictures a second this is a picture of see these big bits here these big wheels they're designed to detect a particular kind of particle called a muon actually and this is a picture of those wheels when they were being installed this is the Large Hadron Collider that machine which stretches remember 27 kilometres around France and Switzerland that's me by the way little white hat on so you get some sense of the size of this thing and that's a picture of this machine when it was being built that's a you see there there's a real person there's a physicist stood there with his with his yellow hat on and building this thing here thing in there those little collisions happen this is a picture of one of the most famous collisions that were generated just about a year ago actually this is famous because we think this is a creation of a particle called the Higgs particle now Higgs particles are very strange they're one of the reasons we built the Large Hadron Collider and we found that they exist and they're very weird indeed the idea is that every bit of space in the universe is filled with them so that doesn't mean space out there just to space out there between the stars it means this room right and in fact it means the space inside you so inside you inside everywhere everywhere in the universe there is a sea of these Higgs particles and our theory was that we get substance mass so you look at our hand it's a solid thing it's made of matter the theory was that it's like that because you're little particles you're subatomic particles that make up your body a bumping into the Higgs particles and in that process of rattling around inside a write off all these Hicks particles that are distributed all across the universe they get mass and that's the reason the fundamental reason you're solid sounds like a very weird theory indeed gets even weirder actually if you ask where did they come from the answer is they condensed out into the universe about a billionth of a second or less after the Big Bang like water condenses onto a window so if you look at a window on a cold winter's day you see ice forming on there on the window in a similar way we think these Higgs particles condensed out into empty space you're interacting with them now which is why you're solid and that is probably one of the first pictures ever taken of a Higgs particle being created in the Large Hadron Collider remarkable thing one thing I want to say and I want to emphasize through this little talk is that the LHC will be there for a decade two decades or more its job now having discovered these weird things is to investigate them in detail now you're what 11 12 13 14 years old and if you fast forward what six years seven years eight years the LHC will still be runnin you can then be a research scientist in just eight years from now on the Large Hadron Collider a lot of universities in Britain my University of Manchester included what UCL and Imperial in London Oxford Cambridge others others universities send people at the age of forty be 21 or 22 so just eight or nine years to CERN to work on these things so I hope one of my hopes is that at least one of you in this room might be in ten years time or nine years time investigating the properties of these mysterious particles we need to know how they behave now we know they exist we don't know in precisely how they work why they work why all this stuff condensed down into the universe a billionth of a second after it began why questions that scientist ask so one of you put your hand up who will it be who would fancy working at CERN and there's plenty yeah it can be more than one either there are plenty of research scientists needed it sir wouldn't that be fascinating that by the way there are other things CERN is looking for it's looking for things like extra dimensions in the universe that sounds strange doesn't it this room is three dimensional so three dimensional means you need three numbers to specify where something is so if I wanted to get over there into the corner and after walk a certain distance that way certain distance that way at a certain distance that way we think there may be or it may be possible that there are other dimensions in the universe they might be curled up they might be about a millimeter above our heads but because light doesn't travel through them we can't see them fascinating they may be discovered at CERN lots of interesting questions so I'm glad that about what 20 of you or something out 25 said you might fancy working they're still gonna be there when you're doing your PhD s if you do degrees in physics or engineering mathematics and so that's CERN one of the great discoveries actually in the last 100 years of physics which was made last year let's move on outwards so I talks about the Big Bang 13.7 5 billion years ago we've talked about what happened first billionth of a second which were investigating absurd these Higgs particles and things fast forward on and about five billion years ago just a bit less and a cloud of dust and gas which was actually made probably by stars that had lived and died and condensed into our solar system now our solar system is a place that we're exploring now in detail and again I'm going to show you a few pictures and give you some ideas of what you might want to work on his solar system exploration in the next ten years or so and but this is the heart of the solar system the Sun it's worth reminding ourselves how large and powerful and remarkable the Sun is and this is a real picture another computer graphic taken by a spacecraft whose job it is to observe the Sun you can fit a million earths into there so to get some sense of scale a million earths inside it surface is about six thousand degrees centigrade or Celsius which is quite cool actually the core 15 million and the atmosphere bizarrely is over a million degrees that's one of the great mysteries we're beginning to understand why you would think of it's rather strange the surface is 6,000 degrees the atmosphere is a million degrees so there are great unsolved mysteries things that we don't know about the way that stars work what we do know is it's burning hydrogen into helium so it's assembling the simplest element in the universe into a more complex element helium and in the process releasing energy it's burning 600 million tons of hydrogen every second into helium fusing it together to make 596 million tons of helium it's losing 4 million tons of mass a second as energy which is why the Sun shines and it despite the fact that it's so big it is so hot and so bright in the sky so there's the Sun move outwards and I wanted to show you this because I think it's a beautiful photograph this is a photograph well a movie of Earth but it's an interesting movie of Earth because you see their Aurora the Northern Lights so it's a it's a movie from a spacecraft in orbit around the pole Earth's pole that will be the South Pole because you can see Australia rolling into view there this is the wind from the Sun interacting with the Earth's magnetic field there's magnetic field protects us it's the thing you detect with a compass protects us from that wind from the Sun but at the poles it gets that the wind from the Sun can get in and it can shake the molecules in the atmosphere of the earth the oxygen and nitrogen molecules and they give off light when they and that's the light you see as the Northern Lights I thought this was a beautiful picture to show of the earth so the question is we understand roughly how the universe evolved from a billionth of a second after it began we understand how solar systems form indeed we've seen many of the solar systems forming how did life begin I started the talk by looking at the eye eye and the catfish and we talked about us how did that begin another one of big questions the answer is we don't know but again this is an area that research is very active in now so if you're interested in biology rather than physics or chemistry or astronomy biology is moving at a creasing ly fast rate and there are really strong firm theories about how life began don't know for sure one of the theories is that there may have begun about 3.8 billion years ago we know that quite accurately actually so not long after the earth formed we see evidence of life appearing on earth one of the theories is it began deep below the oceans of Earth in what are called hydrothermal vents but these are pictures of these vents very very deep you're talking miles kilometers below the ocean surface and it's where little volt undersea volcanoes essentially from the heat from the Earth's core driving up through the ocean floor to make these structures where you get super hot water minerals all sorts of things like carbon all the things you need to make life a cooked almost in these environments and one of the reasons that we think that life may have began deep below the ocean 3.8 billion years ago is remarkably in a way these conditions are recreated in every cell in your bodies so every cell in your body now if you look at your finger or you look at your arm while you look at your friends in next to you the cells in their bodies at doing some of the chemistry that we think occurred on the earth 3.8 billion years ago it's not the chemistry of the earth today the earth was a very strange place 3.9 billion years ago the oceans were very acidic there was no oxygen in the atmosphere because there were no plants to put the oxygen into the atmosphere and yet in a way our cells in our bodies are recreating those conditions what's the answer well the theory goes that that's because life began in those strange conditions all that time ago and that's the way it's always done it so it's almost right to say that when life left the vents it put a bag around this chemistry and took it with it and in a sense you are that bag around the chemistry of the early Earth fascinating ideas theories at the moment but I just met a friend of mine actually I should say at UCL the other day at UCL in London while the universities in central London who's built a little reactor the built a little thing which is recreating these conditions as best as we can as far as we know to see what happens now he's not expecting to anything to crawl out of his test tube but what he is expecting possibly is to see complex molecules the molecules somewhat like the molecules that make up you and me emerging from that little reactor very cutting edge research and over the years that's going to become more and more interesting so I suspect that this area of biology the origin of life is going to get more and more interesting more and more people are going to do it and again in ten years time we're going to need biologists who are interested in the origins of life to go and explore that and just before I finish and take some questions I want to step out a little bit more and keep on this theme of life exploring the solar system in this context to see if we can answer the question are we alone in the universe it's kind of related to those vents because the idea one of the modern ideas in biology is that everywhere what's a theory everywhere you find conditions like that you find life life is inevitable if you get water you get volcanic activity you get the right mixture of things and the right length of time is that right or is it that life is unique or very rare in the universe and earth is a unique place well there are other places in the solar system we've already found where conditions may exist that are similar to those vents this is a picture of Saturn beautiful photograph here's another picture looks like computer graphic it's not it's a photograph taken from the Cassini spacecraft which is in orbit around Saturn now it's been there for many years taking pictures like this and I was talking so I know it one of the one of someone in the lab earlier actually we're talking about Saturn's rings and you see the Rings they're very famous beautiful structures this is a picture ed John the rings are a hundred kilometres a hundred thousand kilometers thick they're made of water ice primarily but they're only if you look at the thickness there it's about 2 or 3 meters imagine how delicate that is one hundred thousand kilometres in that direction 2 or 3 meters in that direction and this is one of the moons of Saturn which was in the picture called Titan fascinating place and there's Titan again again this is not a computer graphic that someone's taken a picture from Saturn in this gaze Cassini is another little moon up there actually see the intricacy of the Rings the interesting thing about Titan is this this is a close-up of Titan this is an atmosphere it's like Earth's atmospheres blue sky that's what you see there the gases in the atmosphere much thicker than the Earth's atmosphere now Titan is a very cold place but it's interesting because we've landed on Titan we landed the European space probe Huygens parachuted through this atmosphere a few years ago now and it landed on mushy wet ground now it wasn't water because it's very cold on Titan it was actually methane so you have a barbecue in the summer you might use one of those gas canisters with methane in these temperatures methane can be a lick quit so Titan is a place where there are rivers of methane there is methane snow falling on the surface there are oceans of methane and people are already speculating that possibly there might be some kind of very strange forms of life on Titan could it be there's lots of liquid there's a lot there are rivers and there are oceans and it's a very strange place but a place that's not covered in water that's covered in methane although there may be some evidence that there may be remains of water perhaps below the surface a very interesting place but we do find water around Saturn this is the black-and-white photograph of a moon and called Enceladus which is quite a small moon it's not much bigger it's about as big as Britain actually it's quite a small place but a Cassini swept over the surface of in salad that's a Saturn by the way so Cassini swept over there over the surface of Enceladus and took pictures and this is one of the photographs it took this is a billion kilometers or more away from Earth this little place look at these plumes rising up from the surface those are water those are jets of water spraying up from the surface of Enceladus which tells us that there must be at least frozen water and perhaps pockets of liquid below the surface of Enceladus could this be a place where we find simple microbes might be too small but it's interesting because there's water there but this is a place where we are very certain there's a lot of water this is a place that we're going to explore with a space mission again in the next 10 15 or 20 years there are plans to send a very dedicated mission to go and look at this moon this is the moon of Jupiter called Europa and this is actually a computer animation of Europa and Jupiter but made from real photographs that were taken by a space probe called Galileo there was an orbit around Jupiter this moon has got an icy crust it's the ice is probably around a hundred kilometers thick but we know that below that ice there's an ocean of liquid water and there's more water in the oceans of Europa than there is in all of the oceans of the earth combined and we think there may be hydrothermal vents it's below that ocean on Europa so one of the great challenges and this is perhaps for 30 40 years in the future so when you're in you're in your 50s perhaps you're a senior scientist at the European Space Agency or NASA and you will be designing missions to burrow through that ice how would you do it no one's really come up with a good idea how would you burrow through 100 kilometers of ice to get a submarine into the oceans of Europa to see what's down there there may be living things in that ocean we don't know it's a challenge to you no one's thought of a way of doing it but everybody wants to go there because as an ocean waiting to be explored and finally before I take some questions nearer to home and nearer to you in time is the exploration of Mars this is the picture of Mars this is one of Mars polar caps their ice caps there's carbon dioxide ice in those caps there's also water in those ice caps so we know there's water ice on Mars and at the moment we're on Mars with a rover called curiosity if you go to NASA's website you can see live pictures essentially every day there are new pictures from curiosity its roving around the surface of Mars to look for signs of water to understand the geology of Mars paving the way for the next missions and this is the photograph curiosity took when it landed beautiful photograph it looks like science fiction again but that is a photograph from the surface of Mars is another one curiosity took a picture of itself you know when you if you've got a mobile phone camera and sometimes just somewhere interesting so you take a picture of yourself curiosity took a picture of itself with its camera just like that I'm on Mars junk email it back home it looks like it can be a graphic that curiosity's head basically where it's cameras are and it took a self-portrait by taking lots of pictures if you could try it probably you take lots of pictures of yourself and then get a computer and assemble all those pictures together curiosity took that picture of itself it looks like it's in a desert somewhere on earth but it's not that was taken a couple of months ago on the surface of Mars by the Curiosity rover what I find fascinating about this is that curiosity is looking for we're beginning to think now that certainly are almost certainly but we know there was water on Mars we know there were oceans and rivers on Mars billions of years ago the Mars has lost its water because it was smaller than the earth and but we don't know where the water went it could be that there is liquid water below the surface of Mars it's one of the things curiosity is interested in how did the wars where did the water go how did it vanish is it still there in some sense there's a European mission part of which is being built in Britain called ExoMars which is going to go to Mars in this decade or just perhaps towards the next decade depending on how they well other funding goes essentially but we need people like you we need British engineers and scientists to work on that mission around the time you're 20 years old that mission will be touching down on the surface of Mars its job is to look for life perhaps there was life there that's now died out perhaps there are still microbes beneath the surface of Mars and that I think is one of the most if I were you I would be very interested in exploring the surface of Mars in the next 10 years or more and finally could it be that in the next 40 or 50 years we step outside the solar system well this is an animation from the European Space Agency of a journey to our nearest star a nearest star it's actually a triple star system called Alpha Centauri there are three suns in orbit around each other two bright Sun like stars very similar to our Sun actually and one small star called a red dwarf which is called Proxima Centauri and just a few months ago we found that there's an earth-sized planet in orbit around one of those stars it's called Alpha Centauri B and so this is an image of what it might be like to journey to that start our nearest star it's only four light years away it only takes light four years to reach us from That star it is possible people can conceive already of building spacecraft that could journey to That star we know there's an earth-like planet around one of those stars although it's too hot to support life it's very cool the star but we now suspect that there may be a solar system around those planets because usually if you find one planet you find more could there be a solar system as complex as ours around a nearby star quite probably that's one of the great challenges for the next 10 or 20 years so that's why I'd like to finish what I wanted to really show you is that we've answered a lot of questions we know how old the universe is pretty much we know how the universe evolved pretty much when our solar systems form pretty much we have theories about the formation of life but there are a huge number of fascinating and fundamental questions many of which should be answered in your lifetime which means that you are the people to answer those questions and now I'm happy to answer your questions thank you very much I know thank you very much professor we know we've got some questions out there on the floor I'm sure you lots of you've got lots of interesting questions you want to ask professor Cox don't be shy about putting your hand up just wait for the microphone to come over to you somebody bring a microphone over to you so that you can ask a question so we can all hear the question but we'd like to put the first question we'd like to let the foot person to have the first question professor Cox as a person who got us to do the original competition and that Zachman he's got a question for you Rosetta's act over here Zach well thank you for applying through the competition because it's been wonderful to visit your school so I want to thank you first for inviting me here ok so if the universe is constantly expanding what does it expanding to it's a great question it was it was if the universe is expanding what does it expand into the standard answer as best we know at the moment is that it doesn't expand into anything because it's space itself it actually space time if you talk to Einstein that's expanding so it's not the right picture to think of a big bang in a pre-existing space like a like imagine this room is the space and the Big Bang cappers in the middle of the room it's not like that at all it seems that as far as we know space and time began at the Big Bang and they've been stretching ever since and so a kind of a related idea it did this very difficult to picture these ideas but they're fun right it is where did the Big Bang happen right you can make you think well we're in this big box of the university a fan over there over there over there it happened everywhere because all the space that's here now in this room was there was made as far as we know at the Big Bang so the Big Bang happened everywhere so it's not expanding into anything it's very difficult to picture that what I should say is that the theory that deals with this that the underpinnings called Einstein's theory of general relativity he wrote it down in 1915 and it's still our best theory of space and time and the theory upon which all these interesting and strange ideas rest you'll learn that it's quite tricky because it's all about curved space but you learn it in a physics degree so if you do a physics degree you start learning about these ideas just you learn about them because the maths is a bit hard to be ranked because it's all about curvy space was that doctor who isn't it curvy we could be wobbly Spacey timey that's what it that's a basic so it's a great question rageh is there a possibility of something exiting universe so like a planet yeah outside the universe yeah well yeah I mean interestingly I just mentioned it very briefly looking for extra dimensions so I don't depends how you define the word universe I mean you could just say it's everything that exists and then obviously you can't have anything outside it but and one of the theories is that we imagine that we're not in this three dimensional space imagine that we just forget one of the dimensions so imagine one sheet so imagine we lived on the surface of a sheet of paper right and imagine the forces of nature particularly light travelled on the sheet and then there's another for scolding the nuclear force the strong nuclear force that sticks your atomic nuclei together imagine that only works on the sheets as well and imagine there's another force called the weak nuclear force imagine that only works on the sheet then what would happen if there were another sheet another universe if you like is floating a millimeter away let's say well you wouldn't see it because light is confined to your sheet you wouldn't feel it because the forces don't come off the sheet there so it could be there now if that's true then we can try and do experiments and so how would we possibly detect it not really well known but there are some signatures of these extra dimensions as they where you can see at the Large Hadron Collider at CERN it's a very speculative stuff so it could be I find this remarkable that there's another universe a millimeter away from your head in a big sheet stretching out infinity in all directions and you just don't perceive it because the forces that are existing exerted arms that hold us together don't travel from one sheet to the next there call them there's all sorts of theories are things called string theory and also that these are called brains so you often see these BR a n yes like brains like membranes and so if you ever want to look on the web you can look for things like M theory which is membrane theory in a way some people say it stands for that where you see all these theories about different sheets and different universes so it's fun stuff it's completely unintelligible please it's good good fun might not be intelligible to you you'd after you'd have to be a really if you like mathematics and you want to practice a lot you want to be a theoretical physicist these are the kinds of things that theoretical physicists are beginning to think about we've got some questions Brian Cox professor Cox has come through from the TS various links today but one of them is from Cameron botting a he's in year 7 and he's at the Henry Beaufort school in Winchester in Hampshire and he asks you work on the Atlas experiment and CERN what exactly is this experiment well Atlas I mean I showed a picture of it in my tool kit sir essentially which one of the four cameras that sit there and take the picture the collisions at the Large Hadron Collider it was built I should say there are physicists from now on Atlas there is something like 35 different nationalities working on Atlas some of it was built in the UK so at that so universities that the you know when you first encounter University it the one of the people here that the one who goes to universe that you'll go there and you'll be taught but you'll be told by people in the main that do research and a Manchester for example we have a big research group myself included who work on Atlas and in the university there's not only the teaching the lecture theatres there are lamps where we built parts of that experiment so we built it there and we took it to Geneva we install this and we make sure it works so the universities are an interesting place to be because you're surrounded I you can wander around you can go to the lectures we can also go and see that your teachers the lecturers who are doing their experiments I mentioned another one with a friend of mine at UCL he's got this ancient earth in a box or he's looking to see how you know how life may have begun in in the university so that's one of the great joys actually of go in there that you can see you see where atlas was built or parts of it were builds if you're going to get in join in actually I mean sometimes when you get to your fourth year we want people to come and do a bit of movie work so you can get involved you start as you go through your university career you start getting involved in the research so the ancient earth is it is is a model of what we could have how life could have started yes it's a wonderful thing it's a tank about that big but it's a little hydrothermal vent but going there bubbling away trying to see what happens so that's what you do with science you want to know how life began you you you you have a theory so you try and recreate those conditions and see what happens it's not likely that you'll make life but you might make complex compounds that the building blocks of life that sounds really exciting it's a sort of thing I'd want to get involved in do we have some more questions on the floors guys can I just ask you keep your hand up till the camera come until the microphone comes to you if you've got a question to ask yep okay so we've got a question over here for a young man over here you tell us your name as we start the question for professor Cox keep your hand up there so we all know it's coming to you time stop when did time start well again and so the standard theory is that space and time began 13.7 5 billion years ago the Big Bang however it's you know the next question is why what happened before the Big Bang and so in that picture you say well there is no time so is it you can't ask the question that's quite unsatisfactory so there are people and again this is this is the future of theoretical physics in many ways who say well maybe you're maybe the universe has been around forever but you've still got to explain why it looks like in our bit of the you it was very Health's and very dense and it's been expanding and cooling ever since so people start building theories about well could it have been I mentioned these were so T about these these brains these sheets that we think of maybe two of those bump together and separated and that looks like a big bang if you're living in one of the sheets the speculative stuff but there are huge problems with our picture of the universe and questions like that brilliant questions that we don't really know the answer to so it's going to take the next generation of the next generation so worth remembering that really that there was no such science as cosmology which is the you know the talking about the origin and evolution of the universe really before Einstein which is 1915 so we're only talking about a science that's at most a hundred years old we didn't know about the Big Bang until the 1950s and 1960s so really you know we're talking probably just about in your parents lifetime or certainly your grandparents if you talk to your grandparents we didn't know there was a big bang when they were at school but we now know there was a big bang but we don't know so we going quite fast but imagine what in your lifetime where we're going to get to I mean in 20 30 years time we've had virtually double the actually heard the amount of time that we've had so far to work these things out so let's take another question over there we've got a guy who was playing in the band at the back there Hayden do you want to ask you a question Hayden I think you've been burning with this question for quite some time to ask for fess okok so let's hear it and I'm interested in astronomy and cosmology so how would you say to get started that's a great question because that's what I when I was your age that's basically what I was asking I was interested in astronomy the way to get into astronomy and cosmology is to do physics at University and the way to do physics at university is to do physics and maths at a-level and anything else you want and so and I should say actually because I've said it before it's really important I wasn't very good at maths at school and I didn't think I was very good at maths and what I found was that maths for me and for many of my colleagues actually work at CERN in astronomy now is something you need to practice at and so I think many people find it the most difficult thing that they do at school it's not in itself I don't think you have to be well I know you don't have to be some kind of great mathematician to be a really successful research scientist but what you need to do is you need to practice at maths no none I found that's why I had to do it actually it wasn't till I got to university I just about managed to scrape through a level and then I got to university and it suddenly I realized that because I was doing a bit more of it I understood how to do it so that's my advice my advice if you only astronomy or cosmology you do physics and maths and you just practice at maths and and it will come to you even if you you might be one you might one of those people it comes naturally - which is wonderful and many people aren't though but but virtually everybody can do it if they do a bit of practice so let's take another question we've got a question from Pablo here at the front guys as a guy here at front good question for you and if there are another substance to create life except for water and if so like are there any other places that you know of which contain our life forces is it that's a really a fundamental question in biology actually at the moment so people ask the question what what do you need what's necessary for life and what are the things that might just have added on to life on Earth and so you need we think you need water and what is a strange thing it is a very complicated liquid indeed and again there's research now a lot of research gone into how water works is simple in some sense it's h2o hydrogen oxygen bonded together but actually the way that those molecules interact is very complicated and and so we think that life is at water is necessary for life we think that carbon is necessary because it forms four chemical bonds and so it can make these long-chain molecules which are necessary things DNA things I have incredibly complex molecules and nitrogen is another thing that we think you need for life and but then there are questions like you need iron for life and we have iron in our blood is that necessary oh that probably not it's probably one of you so it's a very active area of research what was possibly thought now as I kind of mentioned is that in in these vents in oceans which with other oceans on Europa on Jupiter's moon as well as here on earth you you get everything that you might think you need so you have hot water you have acids and alkali you have the rock which has got minerals and you have nitrogen and carbon and oxygen gases like hydrogen sulfide so maybe you need sulfur so so it looks like the conditions are common in the universe for the origin of life the question is we need to find it somewhere else in order to know that it happens somewhere else that's why Mars if you're interested in that one of the best things you can do you do the experiments like we're doing at UCL now or you can go and look on Mars and see if life appeared there as well thank you so we've got a question what's on my shoes oh sorry the question comes from outside here another one this is from grace he's also near 7:00 in Parkside middle school and she asks is why is there oxygen on earth but not in space it's a brilliant question I mean that there is oxygen well that there's oxygen on planets and not in the atmospheres though so the discovers carbon dioxide all over the place for example but free oxygen oxygen molecules in the atmosphere what is it 20-some percent of our atmosphere is is oxygen o2 and that got put there by photosynthesis so it wasn't there before life and it's not stable in the atmospheres of planets so you need to constantly replenish it so on earth photosynthesis does it so plants take carbon dioxide they take water and they rip electrons off the water in the process of photosynthesis which breaks the water apart and the oxygen our atmosphere is coming from water so it's coming from broken-up h2o that's where how it gets into the atmosphere so um you need photosynthesis to do it and which is interesting because what we can do now are we just about on the edge of having the technology - look we were detecting planets by watching them pass across the face of distant stars so imagine from Earth you see a planet float across the surface of the star you see the light of the star dimmer bit and that's one of the ways we detect planets in different solar systems out there in the universe and that the light comes through the atmosphere and we're just about able now to use that light to do what's called spectroscopy on the atmosphere which allows us to tell what the atmosphere is made of so we can start measuring the constituents of the atmosphere on planets around other stars and obviously the first thing we're doing is looking for oxygen and so in the next few years we're going to start having data where we can start to do that again it's one of the things that you could work on you could be one of the people that works on the atmospheres of planets around distant stars who'd have thought that but we can do it and if you see oxygen there you think well likely there's photosynthesis there so there are plans some of that planning I think it's amazing we can actually find out there are other planets now around other stars yes like the one around Alpha Center I'd be is it after this week she's other and to be able to measure the constituents that atmosphere amazed right on the edge so we're just about able to do just beginning to be able to do that and we'll get better and better over the next few years and decades so do we have some more questions here got a question from young lady over here Holly okay what happened when you drop the yogurt in the hydrants it was cool in when did I do that I don't know my teach my old teacher asked me to ask I hope y'all goodness in I don't remember the Hadron Collider I think Oh the Hadron Collider that was I think that was a joke I don't think I did baby no because so you can't drop yeah the thing is that those tubes are sealed tubes where the protons go around and that they're more empty than space actually so you've got to get it's called a very high vacuum so you can't pour anything into the tube because then it would stop working because it's very interesting actually you think that these protons they like electricity really so you've got these usually we had electricity you have a wire and the electrons go down the wire well these are protons they're going around but then there's no wire they're in a tube so it's a very delicate it's a funnel they can you imagine how you manage to send them around 27 kilometres perfectly controlled inside these tubes all these big magnets to do it so it's very high precision so so I don't know I do have a vague memory of someone saying something about yogurt in the Large Hadron Collider but it would it would have been a joke I seem to remember remember hearing sometime that the actual magnets the electromagnets built in CERN some of them were designed and built in Britain come on yes that's cool yeah and and the detectors as well I mean Britain's the em I think the second largest contributor to CERN after Germany so so we a lot of it is British actually and that's the thing it's not you think you know it's in France in Switzerland so it's kind of not part of odds we're the second largest contributor we own that just happens to be that it's in in France and Switzerland but that shouldn't stop you visiting ever because you're perfectly welcome to visit and it should not stop you wanting to work there because it's a British experiment as much as anything else it just happens to be somewhere else and there's some great in the museum there some of those great original bubble chamber detectors are special is it's a fantastic yes you can make is 1954 so if we got another question up from the floor there guys should we go - there's a Yuri Kino he's very keen there he really wants to answer they know Alex let's see if we can keep your hand up Alex so we can see you are very very light tone over to you how do you get the pictures back from curiosity on Mars so quickly oh they go from I mean you're only getting them back at the speed of light that they're sent back by radio transmission but there's actually that there are spacecraft in orbit around Mars so the Rovers now can relay there's the signals up to the ups of the orbiting spacecraft and the orbiting spacecraft and send them so one of the first things that NASA and the European Space Agency did was get these big these big spacecraft into orbit which take a lot of pictures but can also relay pictures back so you don't have to rely on the on the rover itself you just need to get it up to these are the other spacecraft so it's almost like communications network around Mars now and a lot of Rovers there I mean there's still an opportunity and she had one call well my name is Colin but there are two little ones that have been there for a long time and it's still operating I've seen see what's he long called yeah anyway there's many what it's called I know we've got a question from the young lady Hunstanton a hand got but you've been dying to ask this question she's asked it several times in lessons yeah and I can't answer it so Lydia if we do you want to put your hand up so we know who you are Lydia and if you'd like to ask you a question when you've got the microphone there we know you've been asking and there's there hasn't I haven't been able to answer these unless until heaven you can what is dark energy and how is it full ha there's a great reason you can't answer it because the answers don't know and that's what it does if it exists we we know what it does which is that so the measurements recently and again this is only over the last 10 years or so tell us the universe is accelerating in its expansion so the thing is that you wouldn't have expected that what we it's before then before the measurements were made you think the universe begins in a Big Bang and it's flare everything's flying apart space is stretching if you like and then because of gravity because all these things like galaxies in this they all attract each other and so the gravity should be slow in the expansion down because the only force there is gravity which is attracting attracted attracted it's breaking the expansion but what turns out to be the case is that it's accelerating so the rate at which the universe is expanding appears to be getting faster and that's quite a firm measurement now and it was of great surprise so the Einstein knew that you could arrange for this and in Einstein's equations back in 1915 there's a little thing in the equations called the cosmological constant which you can put in and essentially that does this it accelerates the expansion of the universe but then Einstein took it out and actually once said it was his greatest mistake so he thought it was a thing that doesn't really exist it now it serves that it does exist and we really don't know what it is and interestingly though one of the great questions this Higgs thing I talked about at face value the Higgs field would do that so you say blend so this is very nice the trouble is there's so much energy in the Higgs field that it's it should blow the universe apart it's the number is something like 10 to the power 120 times too much now I don't know if you know that notation means 10 with 120 knots after it so that's a big mistake I mean you cannot make if you get a calculator and do any sum you can think of you can't get it that wrong your calculator won't do 10 with 120 knots after it so there's something horribly wrong with our understanding of the way subatomic particles work and the way that gravity works and the way the universe expands and nobody has a clue so again great thing for someone like you to work on it needs someone to come along with a very good idea and say no this is it this is why so we've got this too bizarre pieces of evidence one is the universe is accelerating the expansion and anything is as far as we understand quantum theory it should be accelerating a lot faster and I mean a lot faster have blown itself apart billions of years ago but it obviously hasn't what's going on ways don't work to do there isn't oh can I take one more question from that comes from the TS website and this comes from class five at All Saints maple are we at the center of the universe know that at least I can answer that no and the point is there is no center it goes back to the question I think you asked it was is one of the of their about the Big Bang guy and what we were talking about where did it happen it happened everywhere so everything is receding from everything else because it's space that's stretching so all space was there at the Big Bang and it's always been here and it's always been stretching so there's no Center it's just a slight same way as the it's like saying if you look at the surface of the earth just the surface where's the start well there is it's a surface so there isn't the start it's like that with the Big Bang I think professor Cox we could go on asking you Quakers you know I'm asking you questions but I'm getting the signal here because it's close to time so we give professor Cox a really big round of applause I know we'd really enjoy it thank you thank you I just want to say it's been a real pleasure it's wonderful to see so many so many of you so interested probably everyone's interested in science number of hands that went up saying you want to be scientist I hope at least what I've done this give you a flavor the point about science is there are great unanswered questions some of the fundamental questions but we kind of begin to see how am I answer them so please go and answer them because we need someone to answer them so that's you so thank you thank you very much yeah
