:01:27. > :01:33.Welcome, now as you can see we are joined tonight by an audience, as
:01:33. > :01:38.ever, chosen for their cuss yosity, I will be say theing that by chat
:01:38. > :01:44.to go our guests, Helen Czerski, Alok Jha, what are you speaking
:01:44. > :01:48.about? Massive experiments are they worth it. Gravitational waves
:01:48. > :01:52.travelling before us now. Marcus Brigstocke, how are you? I'm happy
:01:52. > :01:57.you said expert guests and included me. Expert guests and Marcus
:01:57. > :02:02.Brigstocke, how are you? A bit of balance in me! What are you talking
:02:02. > :02:07.about tonight? Nothing. That is a big issue in physics. We will also
:02:07. > :02:12.be saying hi to Mark Miodownik, he will be doing an experiment in a
:02:12. > :02:16.few moments. What better way to kick off Science Club than
:02:16. > :02:24.concentrating on Einstein, a man who changed our understanding of
:02:24. > :02:28.the universe, with his thinking about time, gravity, his thinking
:02:28. > :02:32.still goes on now. We like to look at things from as many different
:02:32. > :02:36.angles as we can. Alok Jha asks the difficult questions about funding
:02:36. > :02:40.big physics experiments. Are you implying we shouldn't fund things
:02:40. > :02:45.that have some sort of immediate application. Absolutely. Following
:02:45. > :02:48.in Einstein's footsteps, Mark Miodownik pulls a fridge to pieces.
:02:48. > :02:52.And comedian, Marcus Brigstocke, gets a crash course in the concept
:02:52. > :02:57.of nothing. When I think of nothing in space, I think of literally
:02:57. > :03:02.nothing, a blank space, you know, Nick Clegg's political future!
:03:02. > :03:08.also ask is it possible to measure the speed of light using cheese on
:03:08. > :03:14.toast. It will all make sense as we go on. You can get exclusive pics
:03:15. > :03:19.and helpful Daoudyles which the web sieltd -- doodle on the website.
:03:19. > :03:23.Here is background on Einstein. The story of physic, is, for the most
:03:23. > :03:31.part, a tale of ever-increasing confidence.
:03:31. > :03:36.In the early 1600, an Italian got the ball rolling, by measuring and
:03:36. > :03:40.observing balls rolling, Galileo also turned pendulum, and dropped
:03:40. > :03:45.different-sized objects off the leaning tower of Pisa to see what
:03:45. > :03:49.would happen. Despite upsetting the Pope, apparently he made God cross,
:03:49. > :03:53.his work became the rock on which modern physics is found.
:03:53. > :03:58.Later, free from angry Popes, Isaac Newton moved things on by
:03:58. > :04:05.abandoning balls and embracing apples. Why, he wondered, did they
:04:05. > :04:09.always fall downwards, not sideways or up? By 1687 he had an answer. It
:04:09. > :04:14.was a force called gravity, which worked on balls and apples. And
:04:14. > :04:19.planets, holding them in nice, predictable orbits around the sun.
:04:19. > :04:23.In the 1800s, James Clerk Maxwell cast his eye over more mysteries,
:04:23. > :04:29.he showed how electricity and magnetisim are related, and can be
:04:29. > :04:33.combined as one force, electromagnetisim.
:04:33. > :04:41.Physics, it seemed, had mastered the universe. All that was left was
:04:42. > :04:44.to plug a few remaining hole. But by 1900 the holes were getting
:04:44. > :04:49.bigger. The latest discoveries didn't build on the old ones,
:04:49. > :04:54.things like X-rays and radioactivity were just plain weird
:04:54. > :05:00.and in a cad way. Lord Kelvin saw dark clouds hanging over the
:05:00. > :05:05.subject. Then, in 1905, a Swiss Patten clerk started a full on
:05:05. > :05:10.storm. 26-year-old Albert Einstein tore up the script. First he
:05:10. > :05:15.claimed life is a kind of wave, but also comes in packet, particles. In
:05:15. > :05:19.the same year he published his famous equation, e=mc2. It says
:05:19. > :05:22.that mass and energy are equivalent. If that wasn't shocking enough, he
:05:22. > :05:26.released the mind-blowing results of a thought experiment. Hold on to
:05:26. > :05:31.your heads. It starts with the assumption that the speed of light
:05:31. > :05:35.in a vacuum is constant. Now imagine that someone watches a
:05:35. > :05:40.spaceship flying very fast. They would see a ship's clock running
:05:40. > :05:45.slower than their own watch. And the ship will actually shrink in
:05:45. > :05:49.size. But for the astronauts inside, all would be normal. Einstein said
:05:49. > :05:54.that time and space can change, they are relative, depending on who
:05:54. > :05:58.is observing them. This is special relativity.
:05:58. > :06:03.His ideas shattered traditional physics, he had opened a door on to
:06:03. > :06:07.the weird world of the quantum. Where cats can be both alive and
:06:07. > :06:12.dead, where God plays dice and where everything is uncertain.
:06:12. > :06:16.His famous equation, led to nuclear energy, without special relativity,
:06:16. > :06:21.the Large Hadron Collider would be pointless.
:06:21. > :06:25.General relativity predicted both black holes, and the Big Bang. An
:06:25. > :06:28.idea now endorsed by both church and science. Galileo would have
:06:28. > :06:32.been pleased. Well done Albert.
:06:32. > :06:40.Our main guest tonight, not only understands Einstein's they arey,
:06:40. > :06:47.but is building on them to advance our knowledge even further. She's a
:06:48. > :06:52.professor of fisks and astronomy, and studies the black holes and the
:06:52. > :06:57.way objects distort the space conten yum.
:06:57. > :07:01.Welcome Janna Levin. How are you.
:07:01. > :07:05.We're a century on from those initial discoveries of Einstein,
:07:05. > :07:09.surely he's old news by now? know, the theory is pretty
:07:09. > :07:14.complicated, it takes a long time to work out solutions, just because
:07:14. > :07:17.Einstein said something like space time is curved, gravity is a curved
:07:17. > :07:20.space time, doesn't mean we immediately know all the
:07:20. > :07:24.implication of that. How much of a revolution is it all the things he
:07:24. > :07:29.was saying? It was incredibly revolutionary, he re-thought the
:07:30. > :07:37.whole way we view the world. It was, in some sense, kind of
:07:37. > :07:43.unprecedented change in par dime and world view. We measured briefly
:07:43. > :07:50.an icon, he was the world's view of what a scientist was? It is hard
:07:50. > :07:53.sometimes to understand why Einstein became so famous, it isn't
:07:53. > :07:57.because so many people grasp or think about the ideas on daily
:07:57. > :08:01.basis. It was probably also the concept that the mind could triumph,
:08:01. > :08:06.in a time when maybe the world wasn't doing so well after two
:08:06. > :08:12.world wars, and a lot of economic strive. And the hair didn't hurt?
:08:12. > :08:16.The hair was awesome! He became very, very celebrated at the time,
:08:16. > :08:21.turning up on red carpets? really is the hugeest thing you can
:08:21. > :08:26.point to. In the 100 years since, and in 3900 years since Newton,
:08:26. > :08:30.there is no question that what Einstein is that big, it is not
:08:30. > :08:34.exaggerated.S What the fundamental, if you had to pick of all the
:08:34. > :08:39.things he tore up, what is the most fundamental change? We no longer
:08:39. > :08:41.think of space and time as absolute, time is not some stage on which the
:08:41. > :08:45.events of the universe are unfolding. Ined stead, time is
:08:45. > :08:48.something that depends on where you are in the universe, and if you are
:08:48. > :08:54.near a black hole, or the earth, or how fast you are moving, relative
:08:54. > :09:01.to somebody else. That is a major shift in really how we think about
:09:01. > :09:06.the nature of reality. But, of course, Einstein wasn't just some
:09:06. > :09:10.crazy-haired theorist work on a blackboard, when he wasn't looking
:09:10. > :09:17.at the universe, put his mind to more mundane matters. Mark
:09:17. > :09:21.Miodownik has the story. In the mid-1920s the big problem Einstein
:09:21. > :09:28.was tackling had nothing do with the laws of physics. But, instead,
:09:28. > :09:34.keeping food nicely chilled. Albert, along with his colleague,
:09:34. > :09:39.filed several of their own patents on domestic refrigerators. It
:09:39. > :09:43.worked on the same fundamentals as your fridge at home, and this one
:09:43. > :09:47.here. You can see those principles in action, with this thermal camera,
:09:47. > :09:51.where cool things like my spectacles are much darker than hot
:09:51. > :09:54.things, like my head. As expected, the inside of the fridge is cold,
:09:54. > :10:00.that is because the heat has been removed from everything, including
:10:00. > :10:03.this egg. But where has it gone? The first law of thermodynamics
:10:03. > :10:08.tells you it can't disappear, it has to go somewhere, it comes out
:10:08. > :10:13.the back of the fridge, that is why the back of the fridge is hot. If
:10:13. > :10:17.you leave the fridge door open it won't cool your house down, energy
:10:17. > :10:22.can't be removed, it is just moved. The real genius of the fridge is
:10:23. > :10:30.how the heat gets extracted, that is down to the stuff inside these
:10:30. > :10:40.pipes. The refridgeant. I have some isobutane, exactly what
:10:40. > :10:41.
:10:41. > :10:44.is in the fridge. Then blow on it, it gets instantly
:10:44. > :10:48.freezing cold. What is happening is the liquid is evaporating, in order
:10:48. > :10:55.to do that, it needs to get heat from somewhere, it is taking it
:10:55. > :11:00.from the lid. Because eyes sow butane has a low boiling --
:11:00. > :11:04.isobutane has a low boiling point, the cooling process happens, it
:11:04. > :11:09.happens even when you lick the back of your hand. This process goes on
:11:09. > :11:14.inside your fridge, rather than a themable of water, it draws heat
:11:14. > :11:24.from your food. It may be the world's smallest ice-cube, but it
:11:24. > :11:25.
:11:25. > :11:30.is an ice-cube. In a fridge it happens in a sealed system of tubes,
:11:30. > :11:38.rather than evaporating, it gets recycled. These tubes are the high-
:11:38. > :11:41.pressure side of the fridge, it keeps the fridge in a liquid state.
:11:41. > :11:45.I'm just getting rid of the insulation, this play as very
:11:45. > :11:49.important role in a fridge, the inside needs to remain cold, and
:11:49. > :11:52.the outside, as we have already said, gets hot. It is sucking the
:11:52. > :11:58.heat out of the food, we don't want the two to talk to each other.
:11:58. > :12:07.We are getting through to the inner layer of tubes, the cold side of
:12:07. > :12:17.the fridge. It is pretty cold. What they do, is they allow the
:12:17. > :12:19.
:12:19. > :12:23.refridge rant, to stay cold. The compresser allows it become a
:12:23. > :12:26.liquid. They brought an experiment into a refrigerator, when they
:12:26. > :12:30.entered people's homes there were problems. Einstein read about a
:12:30. > :12:33.family living in Berlin, two parents and several children,
:12:33. > :12:38.poisoned in their own home, all because the compressor in their
:12:38. > :12:43.fridge had leaked. Accidents like this were becoming increasingly
:12:43. > :12:46.common, because the fuels were toxic or flamable. The death of the
:12:46. > :12:50.family deeply upset Albert. He thought there must be a solution.
:12:50. > :12:55.He set out to redesign the compressor, this is what he came up
:12:55. > :13:00.with. I know it look like a milking machine. It was ingenious, unlike
:13:00. > :13:07.anything that had come before. It used a liquid metal as a pissen to
:13:07. > :13:12.to compress the refrigerant, it was a sealed system, and less likely to
:13:12. > :13:16.leak. It did the same job as a compressor, without any mechanical
:13:16. > :13:20.parts. It never made it to the showroom floor. As the political
:13:20. > :13:25.situation in Europe became frosty, it was harder for Einstein to put
:13:25. > :13:34.his idea into practice. In America a chemist came up with an
:13:34. > :13:38.alternative, safer refrigerant. The doflt of CFCs, he inhaled them to
:13:39. > :13:43.show their safety. They dominated the industry for 70 years and found
:13:43. > :13:49.their way into every home across the world. We know now that CFCs
:13:49. > :13:57.are not toxic to humans, they don't mix very well to the ozone layer,
:13:57. > :14:01.we have gone back to using hazardous refridge ld rants. What
:14:01. > :14:11.happened about Einstein? It never got to the economiesic market, it
:14:11. > :14:13.
:14:13. > :14:19.did get used in nuclear reactors to cool uranium and plutonium.
:14:19. > :14:22.This will lead us on very nicely to our unsung scientist feeture, our
:14:22. > :14:25.chance to acclaim some of these scientists who have done fantastic
:14:25. > :14:28.work, who wouldn't be with the giants of the field, and maybe we
:14:28. > :14:34.think history needs to get better attention to. As for the fridge
:14:34. > :14:39.itself, it never went into production? It didn't. What
:14:39. > :14:43.happened was that initial the CFCs were cheap and convenient and
:14:43. > :14:51.fitted into the current technology, of a that went, and until we worked
:14:51. > :14:56.out that CFCs were very damaging to the ozone layer. We went back to
:14:56. > :15:01.the poisonous stuff? It is in the modern fridge. It comes to the
:15:01. > :15:06.unsung heros Hall of Fame. We know the big hitters, like Newton,
:15:06. > :15:14.Einstein, Darwin and the Galileos. But, you want to nominate, not
:15:14. > :15:18.Einstein, but...That Fridge was Einstein's fridge, but his friend,
:15:18. > :15:23.Leo Sillard, the student, he have the one that spotted the Nazis were
:15:23. > :15:26.starting to regulate uranium. He wrote to Einstein and said we
:15:26. > :15:31.better tell Roosevelt that a nuclear bomb is possible and the
:15:31. > :15:35.Nazis might get one and we should start one soon. He wrote the letter
:15:35. > :15:42.and Einstein signed t later in life he invented this idea of radiation
:15:42. > :15:52.treatment for cancers. He goes in there. Who would you include?
:15:52. > :15:52.
:15:52. > :15:57.going to nominate Carl Swarcfield, his legacy isn't as broad, but
:15:57. > :16:02.during World War I he was a German infantry soldier, working on the
:16:02. > :16:08.Russian front. Between gunfire he was reading Einstein's newly
:16:08. > :16:14.published general theory of relativety. He was the first one to
:16:14. > :16:19.really understand that a possible candidate for curving space time
:16:19. > :16:23.was the black hole. He wrote to Einstein and said despite the war
:16:23. > :16:27.and gunfire I wandered through the land of your ideas. Einstein was
:16:27. > :16:32.impressed with this solution and couldn't believe it was done so
:16:32. > :16:36.quickly and elegantly and he helps them to get published. Einstein
:16:36. > :16:39.believes black holes aren't real. This debate wages after Carl's
:16:39. > :16:42.death for decades until people realise that actually the death
:16:42. > :16:48.state of stars are black holes, if they are massive enough.
:16:48. > :16:54.There's Carl. I'm going to add the guy you
:16:54. > :16:58.mentioned, technically not adding him here this is Thomas Midgely. He
:16:58. > :17:01.invented CFCs which revolutionised it, and then destroyed the ozone
:17:01. > :17:06.layer. That was his second invention, what else did he invent?
:17:06. > :17:11.The other thing was leaded petrol. The guy had lead poisoning, he had
:17:11. > :17:18.to recover for ay, and then went back to sold it to the public, by
:17:18. > :17:21.inhaling it in front of TV cameras. Would he be among one of the
:17:21. > :17:26.greatest polluters in the history of the planet? He's the candidate
:17:26. > :17:31.we know of. I'm not putting him there I'm putting him here, they
:17:31. > :17:36.are still there and remembered by history, but we're not going to
:17:36. > :17:41.shift them to the glowing wall there. If there is detail that we
:17:41. > :17:43.haven't covered about Einstein, we have our aftershowers Science Club
:17:43. > :17:48.after the show, physicists will be waiting for your questions.
:17:48. > :17:54.While you are watching, you can get exclusive pictures, surprising
:17:54. > :17:58.facts and helpful doodles by following us.
:17:58. > :18:02.Our universe seems to be made of up stars, planets and gas, that are
:18:02. > :18:06.clumped together. With vast gaps inbetween them, and even at an
:18:06. > :18:09.atomic level it is pretty much all space. When we sent out Marcus
:18:09. > :18:19.Brigstocke, who knows nothing about physic, to make a film for us. It
:18:19. > :18:23.
:18:23. > :18:28.seems suitable that the question he Like most people, I grew up
:18:28. > :18:32.thinking that space was full of nothing, a vacuum, as empty and
:18:32. > :18:38.cold as George Osborne's smile. You know, it is just the void, with
:18:38. > :18:43.some stars in it and stuff. It turns out that nothing lies at
:18:43. > :18:53.the heart of physics. And figuring out what nothing is has vexed
:18:53. > :18:53.
:18:53. > :18:56.physicists like professor Jim Alkalilly for decade. What did
:18:56. > :19:02.scientists think was up there before Einstein They thought the
:19:02. > :19:06.whole of the universe was filled with the ether, the stuff that is
:19:06. > :19:10.invisible to us, but allows light travel through. That is the only
:19:10. > :19:13.way they could figure out light could reach us from the stars.
:19:13. > :19:19.think that? That is wrong, Einstein came along and said there is no
:19:19. > :19:24.such thing as the ether, he proved it, that was his theory of
:19:24. > :19:34.relativeity. There is nothingness, Einstein said so? Jimmy's taking me
:19:34. > :19:36.
:19:36. > :19:41.to space. The nearest thing to space, in this laboratory.
:19:41. > :19:45.M This is a vacuum chamber, you close the door and suck out all the
:19:45. > :19:52.at tomorrows from inside there, to get -- atoms from inside there, and
:19:52. > :19:55.get as close as you can to empty space. You suck out the atoms and
:19:55. > :19:59.inside there is nothing? Firstly, you can't do all of them, but if
:19:59. > :20:04.you could, there is other stuff going on there. The walls are
:20:04. > :20:08.radiating waves, or particles of light, called photons. You can't do
:20:08. > :20:13.it here, but in space, then you can have nothing? Even in deep space
:20:13. > :20:19.there are still particles, photons, flying about. Even if you could get
:20:19. > :20:24.rid of them, if you manage taking two atoms, this far apart, with
:20:24. > :20:28.nothing inbetween them, that nothing isn't complete nothing. If
:20:28. > :20:35.those atoms can feel each other, if the electrons can repel each other,
:20:35. > :20:38.they are exchanging particles. Photons. Empty space always
:20:38. > :20:47.contains something. It is unavoidable. So you can't have
:20:47. > :20:52.nothing? No, nothing doesn't exist. Really? You haven't read Richard
:20:52. > :20:57.Little John's column! Those tripy sounding particles are not alone in
:20:57. > :21:02.the void. Jim reckons there is a whole party going on out there.
:21:02. > :21:09.Empty space is also filled with forces. The force of gravity is
:21:09. > :21:12.something, and Einstein, in 1915, explained how the universe was
:21:12. > :21:16.acting under graphty. He thought gravity was causing everything to -
:21:16. > :21:19.- gravity. He thought gravity was causing everything to collapse in
:21:19. > :21:23.on itself. We now realise that actually the universe is expanding
:21:23. > :21:29.ever more quickly, and the thing we think that's causing that to happen
:21:29. > :21:33.is something else that we think exists in space, something called
:21:33. > :21:38.vacuum energy. To show me this vacuum energy, Jim
:21:38. > :21:42.has borrowed what appears to be an appliance found in every office in
:21:42. > :21:52.the land. I recognise this, because this is a photo copier, isn't it?
:21:52. > :21:55.
:21:55. > :21:58.Almost. It sound like a photocopier when you witch it on, but this is a
:21:58. > :22:03.sophisticated machine called a cloud chamber. What it does is
:22:03. > :22:09.detect particles. There we go, it is firing up! What you can see in
:22:09. > :22:13.the surface are lines that appear and desappear. Those are particle
:22:13. > :22:18.tracts, particles from outer space come in, they collide with the
:22:18. > :22:22.atmosphere and atom on earth, and prodrues these tracks. What this
:22:22. > :22:26.has to do -- produce these tracks. What this has to do with empty
:22:26. > :22:31.space, even though you have no energy at all, nothing at all, you
:22:31. > :22:35.can still make a pair of particle, an electron and anti-electron.
:22:35. > :22:41.what Jim seems to be telling me, is that the same kind of particles
:22:41. > :22:44.that turn up in the cloud chamber, can pop up everywhere, even in the
:22:44. > :22:47.most distant, barren corner of the universe. When you say nothing, you
:22:47. > :22:52.don't mean the same nothing that I think of when I think of nothing.
:22:52. > :22:58.When I think of nothing in space, I think of literally nothing, a blank
:22:58. > :23:04.space. Nick Clegg's political future. When you say nothing, you
:23:04. > :23:09.know that in any chunk of space, that is a constant state of
:23:09. > :23:14.activity and change? This quantum energy, the quantum fluctuations of
:23:14. > :23:17.these particles being very busy. That looks like it is the
:23:17. > :23:21.explanation for one of these deepest mysteries of physic, which
:23:21. > :23:31.is, what is out there in empty space. What is driving the universe
:23:31. > :23:32.
:23:32. > :23:36.to make it expand. So, nothing is something, and that
:23:36. > :23:40.something may explain the bizarre observation, that the universe is
:23:40. > :23:43.inflating all around us. And just as it couldn't get any
:23:43. > :23:48.stranger, Jim has left me in the dark with this man, who believes he
:23:48. > :23:52.knows why we live in an expanding Cosmos.
:23:52. > :23:56.When we look How can you tell a picture like this, that the
:23:56. > :24:01.universe is expanding faster and faster.
:24:01. > :24:05.We see the galaxies in those image, using telescopes like this to
:24:05. > :24:11.measure distances to the objects as a function of time. What we can see
:24:11. > :24:15.is the amount of distance per unit time is changing. And the universe
:24:15. > :24:23.is accelerating in its expansion. We think what is driving that is
:24:23. > :24:28.something called dark energy. is, as used by the Dark Lord Darth
:24:28. > :24:33.Vader. Dark energy is a term we use for anything that could be
:24:33. > :24:36.explaining this acceleration of the universe. The most favoured
:24:37. > :24:41.explanation we have is something called vacuum energy. If it carries
:24:41. > :24:45.on being this vacuum energy then it will never stop accelerating, and
:24:45. > :24:50.you will end up with a universe where galaxies are flying apart
:24:50. > :24:57.faster than the speed of light. In about 60 billion years we will have
:24:57. > :25:06.what they call the big rip. If we are right, space itself will start
:25:06. > :25:10.to dismantle. Ladies and gentlemen, Marcus
:25:10. > :25:15.Brigstocke. I want to thank you for doing that
:25:15. > :25:18.film for us, it was probably the least enlightning science film ever
:25:18. > :25:24.made in history, from your face alone it was clear you went in with
:25:24. > :25:28.nothing, and came out with less. mean, I thought, one grows up
:25:28. > :25:33.thinking there is a nothing out there, that there is an empty space,
:25:33. > :25:37.and there isn't, at all. That's all right. But when you see that we are
:25:37. > :25:42.being bombarded by things, all of the time. You know there are forces
:25:42. > :25:46.acting on you, even as a punter and non-scientist like me, you know
:25:46. > :25:49.about that. But actual things, passing through this roof now and
:25:49. > :25:53.hitting us. We're all right, but, you know. They are quite tiny
:25:53. > :25:57.little things, some are passing through us and not hitting us at
:25:57. > :26:00.all. Mostly right through us. many hundreds of thousands of
:26:00. > :26:05.millions are going through my thumb right now, it is happening all the
:26:05. > :26:13.time. How many fields are we sitting in right now? Electric
:26:13. > :26:17.fields, magnetic fields, gravitational field s. The Higgs
:26:17. > :26:21.fields? Presumably. When everybody says this used to be fields, it is.
:26:21. > :26:25.They love. That I learned that, and that the universe will rip itself
:26:25. > :26:28.apart. That was nice, that was a fun thing to learn, that the
:26:28. > :26:33.universe is just gradually going to rip theself apart. Obviously, like
:26:33. > :26:36.all of these things, I really did find it fascinating, it has led to
:26:37. > :26:40.millions and millions of other questions in my mind. I find the
:26:40. > :26:46.whole constant expansion of the universe, the basic first question
:26:46. > :26:50.for me is, well expanding, but into what? I'm stumped by that
:26:50. > :26:56.immediately. Expanding into what? It has been explained into nothing
:26:56. > :27:03.because it is going round and I can't get that. It can be infinite
:27:03. > :27:09.and expanding. Not in here it can't. There isn't room enough. Why not
:27:09. > :27:12.ground this with an emnint scientist, it is an every day
:27:12. > :27:17.problem. How many people have headphones with them at the moment?
:27:17. > :27:21.This is essentially what it is like in your pocket at the moment. Nice,
:27:21. > :27:24.top-quality example. This, why does this happen? It is so frustrating,
:27:24. > :27:29.it drives me crazy. It happens to me all the time. There is fis he
:27:29. > :27:35.cans in that? I would say one way of talking about that is to say
:27:35. > :27:42.that there is many more ways that can be tangled than not be
:27:42. > :27:49.tanninged. Many fewer ways for it to be smooth and untangled. It is
:27:49. > :27:54.entrophy, it says the larger number of ways of doing something is
:27:54. > :28:01.entrophe, the chances are higher to have it knotted. Anyone here,
:28:01. > :28:08.tangled, tangled. That is a mess, to be honest with you. Anyone
:28:08. > :28:13.unhang -- tangled. I keep mine in a pouch! That is to tragic. A little
:28:13. > :28:19.pouch, and they are made of a different thing so they are easier
:28:19. > :28:28.to unknot. This won't work now. hope it doesn't. There we go. My
:28:28. > :28:32.knotless pouch, now who looks foolish! It is still you.
:28:32. > :28:35.What complex mathematics, knot theory? They are knotted in
:28:35. > :28:39.different ways, it is not a magic thing that you put it into the
:28:39. > :28:43.pocket and it comes out the same knot. Knot theory there is a whole
:28:43. > :28:48.branch of mathematics that tries to understand the complexties of the
:28:48. > :28:51.way things become knotted. It can have application for things like
:28:52. > :28:54.quantum gravity, and spring theory. Which are about the foundations of
:28:54. > :28:58.the universe. It is the most frustrating thing, that. Because
:28:58. > :29:03.you think that's just happened without me touching t I put it in a
:29:03. > :29:07.bag or pocket, therefore, when I hold it, there is probably one way,
:29:07. > :29:12.if I get hold of the right bit and pull it, it will come out straight.
:29:12. > :29:15.Never once have a lucked out with that, hence, the poach! It is the
:29:15. > :29:19.same argument why your room gets messier rather than cleaner unless
:29:19. > :29:25.you do something. I have a woman comes in. Adding artificial energy
:29:25. > :29:30.to the system. Cheating! She's not artificial, she's real. Do you pay
:29:30. > :29:35.her through the book, or cash thing? It is a Jimmy Carr
:29:35. > :29:39.arrangement, she's from Guernsey! You might think that Einstein's
:29:39. > :29:45.theory affects you in any way, it is all about planets and space, you
:29:45. > :29:55.are wrong. Here are some numbers. Your head might be only 175cms from
:29:55. > :29:56.
:29:56. > :30:02.your feet, but time ticks fast up there. 678quadrillionths of a
:30:02. > :30:08.second. By the end of your life, it is 484billionths of a second older
:30:08. > :30:13.than your toes. Say you took a job at the top of the Empire State
:30:13. > :30:22.Building, that is 8.4 hours day, 260 days a year, for 46 years, you
:30:22. > :30:32.would have worked a colossal slight of a second longer than the people
:30:32. > :30:42.
:30:42. > :30:52.If the sprinter ran 100ms in 9.58 seconds, he would finish six
:30:52. > :31:00.quaddrillionths than those starting If you try to break the land-speed
:31:00. > :31:05.record, then, you would have gained three trillionths of a second.
:31:05. > :31:11.Spend your whole life at that speed and you would half a measure of a
:31:11. > :31:17.second ahead of everyone else. Higher up, as well as going over
:31:17. > :31:25.100-times faster than the eurosta, the International Space Station is
:31:25. > :31:34.over 4 ,000ms above oured head. Spend your entire life up there,
:31:34. > :31:38.and you will be a second younger. Proof that science really can --
:31:38. > :31:42.415,000 miles above our heads, spend your life up there you will
:31:42. > :31:45.be a second younger. Proof that science can really explain
:31:45. > :31:48.everything. It was discovered by Maxwell that
:31:48. > :31:51.the speed of light drops out of electricity and magnetisim.
:31:52. > :31:54.Suddenly there is this huge discovery that electricity and
:31:54. > :31:58.magnetisim, and these electromagnetic fields are light.
:31:58. > :32:02.If you run at a train, it is coming faster than if you run away from a
:32:02. > :32:05.train. Life is not like that. The fact that it is the same, weather
:32:05. > :32:09.you run towards a light beam or away from a light beam, is so
:32:09. > :32:14.strange that everyone thought it was a wrong result. And what
:32:14. > :32:17.Einstein did was say, actually, I think that's right. Everything we
:32:17. > :32:21.see and every measurement we have made, and all we know about space
:32:21. > :32:26.is because of light? Yes. More or less. Are there other ripples we
:32:26. > :32:30.should be looking at? If we are talking about Einstein, we have to
:32:30. > :32:34.talk about gravitational lifts, the idea that if very massive things
:32:34. > :32:37.were to collide, like two black holes, which is the favourite
:32:37. > :32:42.candidate. That they would cause space to ripple around them, like
:32:42. > :32:47.fish swirling in the pond and the water would ripple. Those waves are
:32:47. > :32:49.in the shape of space, if you were standing beside the black holes you
:32:49. > :32:54.couldn't see them and if they collided you wouldn't know, and
:32:54. > :32:59.then all of a sudden you would be squeezed and stretched as they
:32:59. > :33:02.travel through you, and they travel at the speed of life light.
:33:02. > :33:07.space squeezes and stretches, do you feel yourself squeezing and
:33:07. > :33:10.stretching? If it is strong enough you would. If it is strong enough
:33:10. > :33:15.to overcome the electrochemical bonds that hold you together.
:33:15. > :33:19.are they so elusive? They are so weak, so, you know, I can fight
:33:19. > :33:23.gravity with my little arm, the whole of the earth is pulling on me
:33:23. > :33:28.right now, and I can easily overcome it. Gravity is incredibly
:33:28. > :33:33.weak. So, you need something like two massive black holes smashing
:33:33. > :33:38.together. Even then, it's so incredibly weak by the time it gets
:33:38. > :33:42.to the earth, that for a long time people thought there would never be
:33:42. > :33:46.any hope of actually experimentally getting there. We have yet to?
:33:46. > :33:50.have yet to, but the ambition has been decades in the making and we
:33:50. > :33:54.are on the verge. When scientists such as Newton were coming up with
:33:54. > :33:57.theories they could test them immediate lo. Einstein's ideas were
:33:57. > :34:02.so advanced, he had to wait for the technology to catch up to test his
:34:02. > :34:07.they are hey. They have all been proved correct with one outstanding,
:34:08. > :34:15.that is gravitational waves. We went to see how the hunt for this
:34:15. > :34:17.most elusive of physical effects is progressing.
:34:17. > :34:26.Gravitational waves are really elusive things to detect, because
:34:26. > :34:31.of the effect they have on the world around us.
:34:31. > :34:34.General relativity, predicts that mass gravity can warp space time.
:34:34. > :34:41.And that's what gravitational waves are, they are ripples in the fabric
:34:41. > :34:45.of our universe in space time. So here's the problem, a
:34:45. > :34:49.gravitational wave can be passing through me right now, stretching
:34:49. > :34:53.and squishing the space time around But if it is stretching and
:34:53. > :35:01.squishing what is around me, it is also stretching and squishing me.
:35:01. > :35:04.So the difficulty is, that from my point of view, nothing has changed.
:35:04. > :35:09.The business of catching gravity waves is, therefore, incredibly
:35:09. > :35:19.difficult. It requires big, expensive
:35:19. > :35:23.
:35:23. > :35:27.experiments. This is the laser interfrometer,
:35:27. > :35:34.wave experiment. It cost $365 million to put together. That makes
:35:34. > :35:40.its boss, the man under pressure to prove instein right. You see two
:35:40. > :35:45.long arms, there is one down there by you and one past me. They are
:35:45. > :35:48.4kms long each, we shine light down a laser down both of the arms and
:35:48. > :35:52.measure the lengths of those arms. We measure the difference between
:35:52. > :35:55.one arm length than the other. gravitational wave came through,
:35:55. > :36:03.here now, what would LIGO do? Imagine it were coming straight
:36:03. > :36:05.down from the sky. It would make one arm a little longer and one
:36:05. > :36:09.shorter, and that would reverse with the in coming gravitational
:36:09. > :36:13.wave. We measure the difference between the two arm, we would see
:36:13. > :36:16.one arm getting longer, the other getting shorter and back and forth,
:36:16. > :36:23.it would trace out the same wave form as the gravitational wave.
:36:23. > :36:32.are using the laser as a ruler, these two arms are giant rulers in
:36:32. > :36:35.space time. That is right. LIGO's 4km arms can detect movement a
:36:35. > :36:39.thousand if diameter of the smallest nucleus. That is looking
:36:39. > :36:47.at the entire width of the Milky Way, and noticing something the
:36:47. > :36:50.size of your thumb move. In 2005, Joe's team set their trap for
:36:50. > :36:53.Einstein's theoretical wave, all they had to do was wait. Before you
:36:53. > :36:57.built this, you must have been able to make predictions about the sorts
:36:57. > :37:05.of waves you thought you would see. Have you, were you right, do you
:37:05. > :37:11.know? We haven't seen, we haven't detected any waves yet.
:37:11. > :37:19.For seven years the detectors have been working. Waiting. For the
:37:19. > :37:24.universe to light up. For LIGO to detect a gravitational wave, it
:37:25. > :37:31.needs a powerful source. A massive collision between neutron
:37:31. > :37:37.stars, or black holes would do it. So would a supernova from a nearby
:37:37. > :37:42.massive star. The resulting gravitational wave would have to be
:37:42. > :37:49.big enough that at its current sensitivity, LIGO, would be able to
:37:49. > :37:51.watch the wave go by. Do you know why haven't you seen
:37:51. > :37:57.anything, you built it because you thought you would see anything,
:37:57. > :38:01.what happened? So, in a particle physics experiment, you shine a
:38:01. > :38:05.beam on to a target, or shine a beam into another beam and you
:38:05. > :38:08.create the events, and then you can count them. We are not a particle
:38:08. > :38:12.physics experiment, nature has to send us the advance, nature has to
:38:12. > :38:15.create the sources. We have estimates about how many of the
:38:15. > :38:21.sources are out that there that we can detect. It was a bit of a long
:38:21. > :38:26.shot that we would be able to see one, with the initial LIGO
:38:26. > :38:32.sensitivity, that is why we have to look for a better detector.
:38:32. > :38:37.isn't giving up yet. LIGO is getting an upgrade, to advanced
:38:37. > :38:43.LIGO. The new optics in Joe's laser rulers, have some of the smoothest
:38:43. > :38:47.surface on earth. The thing about these waves that
:38:47. > :38:52.really gets me, is they are really subltle. We have these great big
:38:52. > :38:55.long arm, and even then to measure the difference in space time, we
:38:55. > :38:59.need it to be really accurate, because it is such a tiny tiny
:38:59. > :39:02.difference. These will make this detector much more sensitive to
:39:02. > :39:08.able to detect even smaller differences? That's right, and it
:39:08. > :39:13.is very pretty, too, isn't it. are stunning.
:39:13. > :39:19.I feel like I'm looking at the cleanest thing I have ever seen. It
:39:19. > :39:24.look atomically perfect. When LIGO's laser is bounced between
:39:24. > :39:28.these flawless optics, Joe will be able to look out for much longer
:39:28. > :39:31.wavelengths. Increasing the sensitivity of the instrument, and
:39:31. > :39:41.allowing a wider range of potential gravitational wave sources to be
:39:41. > :39:43.
:39:43. > :39:46.seen out there in the universe. We have been joined by Helen, who
:39:46. > :39:50.made that film for us. Helen, they have been seven years looking and
:39:50. > :39:52.they think they won't see anything for five years? They are in the
:39:52. > :39:57.process of upgrading it. This experiment has actually been going
:39:57. > :40:01.on for a long, long time. The idea to test for this started in the 50s,
:40:01. > :40:06.people have been refining their methods, and this last upgrade they
:40:06. > :40:10.think they are going to get it. have two arms heading out at a 90
:40:10. > :40:14.degree angle, you send light bouncing out 4qms and back again,
:40:14. > :40:17.if that doesn't -- 4kms and back again f that doesn't happen it is
:40:17. > :40:22.because space time has been distorted? You set it up with one
:40:22. > :40:26.laser beam, you split it into two, those are identical. So you send
:40:26. > :40:30.them down identical arms and back. If one of those arms changes length
:40:30. > :40:34.and the other one doesn't, or if both change, when they get back
:40:34. > :40:39.they won't match up any more. You know you have seen a change in
:40:39. > :40:42.space time. They are refining it, in five years they think it will be
:40:42. > :40:45.refine today see something there, or be ready when something arrives?
:40:45. > :40:48.To be ready when something arrives. It could have happened a billion
:40:48. > :40:53.years a we are just sitting here waiting. We have five years
:40:53. > :40:58.relative to a billion, we have to hurry. If there is any detail about
:40:58. > :41:05.special relativity we haven't word, we have our afterhours science club
:41:05. > :41:09.standing by, we have a top physicist standing by to answer
:41:09. > :41:14.your questions. Alok Jha poses a thorny question, can we afford big
:41:14. > :41:16.ticket physics experiment. We try to track down Einstein's brain.
:41:16. > :41:19.One thing you will keep hearing when we discuss this sort of
:41:20. > :41:22.science, is the speed of light being a constant. It is incredibly
:41:22. > :41:25.fundamental to the whole thing. It is a fundamental fact of the
:41:25. > :41:29.universe. As such we should be able to take ownership of that, we
:41:29. > :41:33.should all be able to measure the speed of light. Mark, you were
:41:33. > :41:38.going to show us show. Exactly would presume this is technically
:41:38. > :41:42.done with telescopes and planets? You can do it that way if you want.
:41:42. > :41:46.The big science, whatever way you want. We can do it by making cheese
:41:46. > :41:50.on toast. That is because radio wave, X-rays, and microwaves, are
:41:50. > :41:54.all types of light. Same speed? Same speed. It is not unreasonable
:41:54. > :41:58.to use a microwave to do the experiment. And that brings us to
:41:58. > :42:04.what a wave is. And so, here is a wave, and it's a certain length,
:42:04. > :42:10.that is this wavelength, it goes that length a number of time per
:42:10. > :42:15.second, that is the freakcy s you times the freak -- frequency, you
:42:15. > :42:20.times the frequency by the length. We will put it into the microwave,
:42:20. > :42:23.I can't touch the cheese. This is genuinely a fun thing to do around
:42:23. > :42:28.a cheese phobic person is wave cheese in their general area. This
:42:28. > :42:32.is not a childhood thing? It is actually disturbing. You actually
:42:32. > :42:36.have a problem with it? I have always had it. I should have been
:42:36. > :42:43.more sensitive to, that generally this show is cool with that kind of
:42:43. > :42:51.stuff, but it is funny to do that. I'm sorry, I'm being insensitive.
:42:51. > :42:54.That goes in. Put that in the Mick crow wave. It is non-standard
:42:54. > :42:59.because we have small wooden blocks? We have taken the thing out
:42:59. > :43:04.that goes round. Because when the wave is bouncing back and forth in
:43:04. > :43:14.this, it gives it hot spots and cold spots. If we get it going.
:43:14. > :43:16.
:43:16. > :43:23.is a student of physics here? You, fabulous. I'm a this eroatition.
:43:23. > :43:27.You have used a ruler? This side. Here we go. Lovely, that's perfect.
:43:27. > :43:33.You can see the hot spots and it has been left over the cold spot.
:43:33. > :43:38.Should we go for the centre of the piece there. If the theory is
:43:38. > :43:47.correct, it should be half. really aren't good with a ruler,
:43:47. > :43:52.are you! We don't care about the bread. Think of the budget this lab
:43:52. > :43:57.works on. Let's go for 6.5. That means the wavelength. For a
:43:57. > :44:06.microwave that is a fairly big wave. It is micro, though, because it is
:44:06. > :44:09.13cms, which is 0.13 of a meeter. 0.13 of a metre, we we are half way
:44:09. > :44:13.there, what about the frequency? need to make an observation
:44:13. > :44:18.independent of that, otherwise we will have our numbers compounding.
:44:18. > :44:21.Can we not use him, he almost blew it in the first part. I saw the
:44:21. > :44:28.things. What we need is someone who can make an observation on the back
:44:28. > :44:38.of the microwave, so you can see the frequency, could you read that
:44:38. > :44:44.
:44:44. > :44:49.number? 200 450 -- 2,450 megaherts, that is the frequency, which is
:44:49. > :44:53.2.45X10 to the 9. We have to multiply those two to get to the
:44:53. > :45:02.speed of light. I can tell you are doing that in your head.
:45:02. > :45:12.Rainman. Somebody get a phone out. Do you want me to type it in.
:45:12. > :45:14.
:45:14. > :45:17.times 2.145. That will be by ten to the eight. 0.3185. That is 3.2
:45:17. > :45:21.times ten to the eight metres per second. I'm definitely asking this
:45:21. > :45:31.one, does anyone know what the actual speed of light is. We have
:45:31. > :45:34.
:45:34. > :45:43.19 physics students here. 2.9 792. Not in that detail! To one decimal
:45:43. > :45:47.point it is 3.0 by ten to the eight. 0.2 off. That is remarkable with a
:45:47. > :45:51.simple experiment and get that close. I'm going to test this, if
:45:51. > :45:55.you average it out, if you have someone of those, bread and cheese
:45:55. > :45:59.at home, try it. Send me pictures of cheese on toast, clog up my
:45:59. > :46:05.account with that kind of thing and the average value. Very good, give
:46:05. > :46:11.Mark a round of applause. Einstein did a lot of his here toising with
:46:11. > :46:15.thought experiments, just -- they areising, with thought experiments,
:46:15. > :46:20.technology has caught up with his thinking and allowed us to test the
:46:20. > :46:29.theories, it doesn't come cheap, can we afford some of the huge
:46:29. > :46:32.science experiments. Alok Jha examines the issue. The big ideas
:46:32. > :46:36.in physics need big experiments, whether you want to understand the
:46:36. > :46:46.tiniest fundamental particles, or work out dark matter in the
:46:46. > :47:11.
:47:11. > :47:14.universe, you need progressively Are the price tags you need for
:47:14. > :47:24.experiments like these on fundamental science, are they just
:47:24. > :47:27.
:47:27. > :47:37.a bit too high? In Texas, like nearly 15 miles of -- lie nearly 15
:47:37. > :47:39.
:47:39. > :47:42.miles of disused tunnels. This was going to be the
:47:42. > :47:52.superconducting, supercollider. But after ten years work, Congress
:47:52. > :47:53.
:47:53. > :47:58.pulled the plug on all funding. Project director Roy watched $2
:47:58. > :48:04.billion come to nothing. How much bigger would this have
:48:04. > :48:12.been compared to the large hide dron collider? Basic skiez is three
:48:12. > :48:16.times larger the hide dron collider at SERN. Why did it try up? A new
:48:16. > :48:24.President, the Cold War had ended. Congress needed to control spending,
:48:24. > :48:27.as now, it needed a symbol for its responsiveness to the issue. We
:48:27. > :48:32.became a spectacular version of that symbol. I have no doubt, had
:48:32. > :48:42.we continued on the plan we were on, that we would have discovered the
:48:42. > :48:55.
:48:55. > :49:01.Higgs a decade ago, or more. In the UK, Sir David King was
:49:01. > :49:05.Government science adviser to the Blair administration. He questions
:49:05. > :49:09.whether megaprojects like the recent quest for the Higgs boson
:49:09. > :49:15.will ever repay their investment. The theory of the Higgs boson has
:49:15. > :49:20.been around for 40 years plus, new discoveries, which will take us in
:49:20. > :49:24.new directions are yet to emerge from SERN. Are you implying we
:49:24. > :49:28.shouldn't fund things that have some sort of immediate or medium-
:49:28. > :49:31.term application? Absolutely. Why limit ourselves to particle physics.
:49:32. > :49:37.We have a whole range of challenges ahead of us in the 21st century.
:49:37. > :49:41.And the question is, whether we should now divert funds into
:49:41. > :49:48.meeting some of these other challenges. Energy technology, for
:49:49. > :49:52.example, brain science, are we funnelling enough if into research
:49:52. > :49:55.over Malaria. There are all these issues around the world where I see
:49:55. > :49:59.a shortage of funding. This very exciting physics we are talking
:49:59. > :50:07.about now has to be played against all these other demands in the
:50:07. > :50:11.research field. You can see Sir David's point, we are in the middle
:50:11. > :50:15.of a global recession, is it really right to divert so much money away
:50:16. > :50:24.from these big problems, and into something like fundamental physics,
:50:24. > :50:34.where, frankly, sometimes it is hard to see what the point is.
:50:34. > :50:35.
:50:35. > :50:38.But there is another way to pursue physics, that is quite affordable.
:50:38. > :50:48.The perimeter institute at Waterloo in Canada, is devoted to the
:50:48. > :50:52.cheapest form of science, pure theory.
:50:52. > :50:59.Every day dozens of the world's finest minds are paid to come
:50:59. > :51:04.together and make like Einstein. They sit, and they think.
:51:04. > :51:10.Neil is director of the institute. Do you think that Theoretical
:51:10. > :51:15.Physicists have a bit of an image problem. You assume Theoretical
:51:15. > :51:22.Physicists are slightly strange, don't like to talk to people.
:51:22. > :51:25.Bang Theory. For example! Yes. Theoretical physics has this
:51:25. > :51:29.reputation because, and to some extent it is deserved. There are
:51:29. > :51:37.many strange people who to it. You have to be incredibly focused,
:51:37. > :51:42.incredibly driven, have a lot of hutzpah to imagine you know what
:51:42. > :51:45.happened at the Big Bang. theoretical fistics is so hard to
:51:45. > :51:49.grasp, how can you know if this work gets any worthwhile results?
:51:49. > :51:53.It is very hard to predict the impact of the kind of discoveries
:51:53. > :51:58.being made here. The one thing I would predict with some confidence,
:51:58. > :52:04.is that an entire institute like this, will, in ten or 20 or 30
:52:04. > :52:09.years be judged on the discovery of one person, who discovers something
:52:09. > :52:13.completely unexpected, which changes our picture of nature, and
:52:13. > :52:20.which has spin-off which we cannot now foresee. That sounds great, why
:52:20. > :52:26.don't you put even more money into theoretical physic, do you ever get
:52:26. > :52:32.jealous at places like at the Large Hadron Collider, they have billions
:52:32. > :52:37.to do their experiments, do you ever think you wish you had some of
:52:37. > :52:40.their cash? I never get jealous of experimentalists, in my view, they
:52:40. > :52:43.are busy with all the technical challenge of the they arey, we have
:52:43. > :52:47.to focus all of our energise on developing theories, to the point
:52:47. > :52:50.they can be tested. So there is extremely strong interaction
:52:50. > :53:00.between theory and experiment. And I would say, the pointless thing
:53:00. > :53:02.
:53:02. > :53:06.would be to support one without the other. You have to have both.
:53:06. > :53:10.bizarre art imitating life fact, that film you just saw is the most
:53:10. > :53:20.expensive film we have made in the entire series! The beneficiary of
:53:20. > :53:22.that, Alok Jha, it can't get more and more expensive? It will, the
:53:22. > :53:25.next generation of particle colliders, the reason all the
:53:25. > :53:29.countries work together, all the countries in the world, because it
:53:29. > :53:32.is so expensive. Billions of pounds and dollars to do this stuff, the
:53:32. > :53:37.next generation will be even more expensive, because they want to be
:53:37. > :53:44.more sensitive, get to even Tyneier scales to check the sorts of don
:53:44. > :53:50.tinyier scales to check the sort of things that Janna and others want
:53:50. > :53:55.to know about. With SERN people want to talk about the Worldwide
:53:55. > :54:00.Web? Medical scanners, Worldwide Web, all comes from the technology
:54:00. > :54:06.to examine the particles in extreme amounts. These things have repaid
:54:06. > :54:12.investment we have made times over. Do we fetishise particle physics,
:54:12. > :54:15.saying they are answers to unlock the universe, we used phrases like
:54:16. > :54:20.changing the view of the universe. It is an easy sell this kind of
:54:20. > :54:24.physic, do we put too much into it? Could you look at it like this,
:54:24. > :54:27.particle physics and these extreme experiments, even in cosmologyy,
:54:27. > :54:30.they are like venture capital, you shouldn't put all your money into
:54:30. > :54:33.it, but they are the things that will inspire the next generation of
:54:33. > :54:36.people. They are the things that might have the amazing results you
:54:36. > :54:40.can use in energy technology, something of the future, but is
:54:40. > :54:45.also good to know this stuff. not asking you to talk your field
:54:45. > :54:51.out of money. Do we have a tepbtd tendency, is it an easy result --
:54:51. > :54:57.tendency, is it an easy result to talk people into a cheque? If you
:54:57. > :55:01.look explanations about the Higgs people talk about the discovery of
:55:01. > :55:05.Higgs at the Large Hadron Collider where it was discover. People have
:55:05. > :55:11.to hear it ten or 15 times, it is not an easy sell. There is the case
:55:11. > :55:16.that we have this natural human instinct to ask questions about our
:55:16. > :55:21.origin, and where we stand in the universe, and what are these
:55:21. > :55:26.elaborate systems. It is simply impossible to quench that. You work
:55:26. > :55:32.in material, predominantly, Mark, given a cheque for a billion, what
:55:32. > :55:35.would you do, would it revolutionise the field? Energy is
:55:35. > :55:39.our biggest problem at the moment, making energy without heating the
:55:39. > :55:44.world. We have the technology that will do the job, solar cells,
:55:44. > :55:48.material science came up for solar cells, we could have solar cells on
:55:48. > :55:52.every roof, why not do it. Because we haven't decided as a culture to
:55:52. > :55:56.go for that goal. We have political things, cheap oil, nuclear power,
:55:56. > :55:59.we have people fighting for wind. But we should just go for solar,
:55:59. > :56:05.the stuff is raining down from the sky. You just have to collect it
:56:05. > :56:09.and we're done, no more digging for oil, no more nuclear waste, just
:56:09. > :56:12.collect the stuff. We can do it, give us the money. We have a clever
:56:12. > :56:21.science interested audience, in the current climate can we justify
:56:22. > :56:27.spending this amount of money on big ticket science experiments plus
:56:27. > :56:30.for yes, and minus for no. It is rigged. Anyone who is a student of
:56:30. > :56:33.physics or involved in physics leave your hand up and the rest put
:56:33. > :56:38.your hands down. Interesting enough, the physics people aren't sure they
:56:38. > :56:42.want the cash at all. I'm going to give it to yes, in
:56:42. > :56:46.this room, for what that's worth would be in favour of that. That
:56:46. > :56:51.seems to be about an 80/20 split in that. Of course these debates
:56:51. > :56:58.continue on-line all the time. You can check our Twitter account.
:56:58. > :57:05.Join in with the hashtag. Sorry, we have vt, if you ever want
:57:05. > :57:13.to see Einstein's brain, this is it. That is the brain that came up with
:57:13. > :57:18.all the stuff that was on there. That is the man examining the brain,
:57:18. > :57:25.enormously closely. This is interesting, Einstein died in 1955,
:57:25. > :57:28.the on-call pathologist, decided we have this amazing guy, what makes
:57:28. > :57:32.him like that, he took the brain without any permission. He didn't
:57:32. > :57:36.publish any papers and he lost his job because of it. Not because he
:57:36. > :57:41.stole Einstein's brain. No, that's fine? But because he couldn't
:57:41. > :57:45.publish papers as a result. Because he didn't do good research
:57:45. > :57:47.afterwards. That is an undignified way to end. Fabulous, Einstein's
:57:47. > :57:54.brain. Some people did see experiments on the brain to find
:57:54. > :58:00.out what it was about it that might have been clever. They found that
:58:00. > :58:03.the parital lobe, at the front, was 20% bigger than normal, he was much
:58:03. > :58:06.cleverer than everyone else. That is how we know he was clever
:58:06. > :58:11.because that bit of the brain was bigger. Scientists will work it out
:58:11. > :58:18.that was the truth. We are nearing the end of the show. Thank you to
:58:18. > :58:24.our reporters, Helen, Alok and Mark. A round of applause. And, our
:58:25. > :58:28.wonderful guest, Marcus Brigstocke, and of course, Janna Levin. Which
:58:28. > :58:34.only leaves to us reason out what we have learned here tonight, the
:58:34. > :58:38.lessons are multiple. Cheese is constant throughout the universe,
:58:38. > :58:42.physics is becoming too expensive we will never know what it really
:58:42. > :58:46.means. The biggest thing is, don't steal brain, I'm always stressing t