BBC Zero Absoluto A Corrida Rumo ao Zero Absoluto Episódio final

a century ago the great polar explorers were pushing further and further towards the coldest places on earth the North and South Poles the competition to reach these goals was matched by a less publicized but equally daunting scientific endeavor the attempt to reach the coldest point in the universe absolute zero this mysterious barrier was a physical paradox as tantalizing as the speed limit of light which can also never be exceeded it was a frontier so enticing that rival physicists from all over Europe began a race towards this absolute limit of coal this is a story of

showmanship setbacks rivalry and despair the stakes were high for the winner there was glory and the chance of a nobel prize for the loser the prospect of being a forgotten foot soldier of science when explorers ventured into the Antarctic they experienced some of the coldest temperatures on earth reaching down to minus 80 degrees centigrade but this was nothing compared to the ultimate limit of temperature absolute zero at around minus 273 degrees only in a laboratory by liquefying gases could adventurers take the first steps towards this Holy Grail a place uh turley drained of all thermal

energy among the front runners in the race towards absolute zero was James Dewar a professor at the Royal Institution in London it will be the greatest achievement of in 1891 he gave one of his celebrated Friday night public lectures on the wonders of the super-cold to celebrate the centenary of his great predecessor Michael Faraday it is sent to a temperature within five degrees of zero we'd open up new vistas of scientific inquiry which would add immensely to our knowledge of the properties of matter James Dewar is a canny arm and I think very ambitious practically

minded Scottish scientist he could really show both his colleagues and of the fee-paying audiences who came to these immensely successful brilliantly engineered lectures are some of the secrets of nature take this rubber ball it bounces well I think you'll agree but let's see what happens after a few seconds of motion in liquid oxygen Dewar invented the vacuum flask to carry out his research and it is still called a Dewar to this day now let's see what happens this phantasmagoric aspect of science always helped science to be accepted by the public though it is a little

mystifying it did play a role of having society having the public accept that these weird people in the laboratories are doing truly interesting if not magical things james jurors life was defined by the cold as a boy he used to skate on a frozen pond in Scotland he claimed in later life that his most formative early experience resulted from an accident on the ice you have to do her fell through the ice he was rescued but when he got home he they discovered that he had rheumatic fever I would put him in bed for eight

months and he was in danger of having a limb to atrophy for Paul T and so the village joiner set him tasked to develop his limb especially his hand and one of the tasks was to make of violin and he developed a great deal of mechanical aptitude which stood him in very good stead in later year when he had to create apparatus for his use doers dream was to take on the mantle of the Royal institution's greatest scientist Michael Faraday seventy years earlier Faraday had done experiments showing that under pressure gases like chlorine and ammonia

liquefy and as these liquids evaporate their temperature drops dramatically Faraday was curious to see if this method of pressurizing gases into liquids could be used for all gases but some gases what he called the permanent gases would not liquefy no matter how much pressure he applied so he abandoned this line of research Faraday's was a mindful of subtle powers of divination into nature's secrets and although unable to liquefy the permanent gases he expressed faith and the potentialities of experimental inquiry the lowest point of temperature attained by Faraday was minus 130 degrees centigrade for over 30

years no one could reach a lower temperature than minus 130 degrees Absolute Zero remained an elusive and very distant goal now Michael Faraday in the early to mid 19th century had left a kind of forlorn frontier for physicists and chemists what he called the permanent gases hydrogen nitrogen oxygen which no means whatsoever seemed to be able to liquefy and this was a kind of no man's land which one could not cross and that was a standing challenge for the scientists of the later 19th century it must be possible to turn these gases into pure liquids

it was not until 1873 that a Dutch theoretical physicist van der waals finally explained why these gases were not liquefying by estimating the size of molecules and the forces between them he showed that to liquefy these gases using pressure they each had to be cooled below a critical temperature at last he'd shown the way to liquefy the so-called permanent gases oxygen was first and then nitrogen reaching a new low temperature of almost minus 200 degrees centigrade only the last of the permanent gases remains to be liquefied hydrogen in the vicinity of minus 250 degrees centigrade

it will be the greatest achievement of our age a triumph of science duo was determined to be the first to ascend what he called Mount hydrogen but he was not alone a competitor Dewar feared most was a brilliant Dutchman heike kamerlingh honest gambling honors was a younger than doer and to a certain extent looked up to the Scotsman as his senior doer didn't have the same if you'll pardon the expression warm feelings towards his rival in the race for cold doer recognized that camel Ling honest had a new radical approach to science and was planning

an industrial scale lab when almost took over the physics laboratory Leiden he was only 29 years old and well he gave his inaugural address here in this lecture room the big lecture room of Academy building of Leiden University and it was all there he was explaining what to do in the next year's and he was talking about liquefying gazes making good physics famous abroad and well it was amazing how farsighted all those fittings were Kamel analysis lab was more like a factory he recruited instrument makers glass blowers and a cadre of young assistants who became

known as blue boys because of their blue lab coats later he set up a Technical Training School which still exists to this day jeweler and honest could not have been more different Dewar was very secretive about his work hiding crucial bits of apparatus from public view before his lectures honest on the other hand openly shared his lab steady progress in a monthly journal honest was the tortoise to juwes hare in the case of doer you had a brilliant experimenter a person who could actually beat the instruments himself and a person who really believed in the

brute-force approach and that is have your instruments set up your experiment and try as hard as you can and then you'll get the results you want to get in the case of Camila Hannes you have a totally different approach he is the beginning of what later on was known as big science unlike juoh honest thought detailed calculations based on theory were vital before embarking on experiments he was a disciple and close friend of Van de vars whose theory had helped solve the problem of liquefying permanent gases though their approaches were different kamilly honest and juoh

used a similar process in their attempts to liquefy hydrogen their idea was to go step by step down a cascade using a series of different gases that liquefy at lower and lower temperatures by applying pressure on the first gas and releasing it into a cooling coil submerged in a coolant it liquefies when this liquefied gas enters the next vessel it becomes the coolant for the second gas in the chain when the next gas is pressurized and passes through the inner coil it liquefies and is it an even lower temperature the second liquid goes on to

cool the next gas and so on step by step the liquefied gasses become colder and colder each one is used to lower the temperature of the next gas sufficiently for it to liquify in the final stage where hydrogen gas is cooled the idea was to put it under enormous pressure a hundred and eighty times atmospheric pressure and then suddenly release it through a valve this would trigger a massive drop in temperature sufficient to turn hydrogen gas into liquid hydrogen at minus 252 degrees just 21 degrees above absolute zero here was the risky bit because his

apparatus was on going down in temperature getting very very cold so very fragile quite easy to fracture while at the same time the pressures he was working at were very very high so the possibility of explosion he took the most amazing risks both with himself he was a lion of a man in terms of courage and with those around him all the equipment he was working with could have crumbled or blown up and more than occasionally it did juror had many explosions in his lab several times assistants lost their eyes as shards of glass catapulted

through the air in the notebook he actually writes touch down many details of what happened in the apparatus but not what happened to his assistants so somehow you get the impression that the paralysis is more important than the assistants well the assistants seem to have been quite loyal to him because I stayed working I mean if you look at the picture of Joe lecturing he's there two assistants there one of whom has lost his eye but the painter manages to portray him with his lost eye facing the other way so you don't actually see it

in the picture so clearly there was something going for jira with his assistants in that they kept that sort of loyalty in a way that would be almost inconceivable in Norden world over in Leiden on s was facing anxious City officials who were so worried about the risk of explosions that they ordered the lab to be shut down Dewar wrote a letter of protest on behalf of honest but the Leiden lab remained closed for two years owners had to wait and to wait and to wait Dewar was already starting his liquefying hydrogen and almost had

the apparatus to do so - but it just couldn't start so we had lost the battle before it was even become here is 1898 tor has been working on trying to liquefy hydrogen for more than 20 years and he's finally ready to make the final assault on mount life by using liquid oxygen they brought down the temperature of the hydrogen gas to minus 200 degrees centigrade they increased the pressure till the vessels were almost bursting and then opened the last valve in the cascade shortly after starting the nozzle plugged but it got free by good

luck and almost immediately drops of liquid began to fall and soon accumulated 20 cubic centimeters juror had liquefied hydrogen the last of the so-called permanent gases to prove it he took a small tube of liquid oxygen and plunged it into the new liquid instantly the liquid oxygen froze solid now he was convinced he had produced the coldest liquid on earth and had come closer to absolute zero than anyone else Durer thought that he had done the most amazing feat of science in the world that he would have beat immediately celebrated for them and get whatever

prizes they were available and that didn't happen I think for doer it was the ambition of a mountain air you've climbed the highest mountain peak that you can see in the range around you and just as you get to the top of the peak there's an even higher mountain just beyond that mountain was helium a recently discovered inert gas Vander vials theory predicted helium would liquefy as an even lower temperature than hydrogen at around five degrees above absolute zero now all Dewar had to do was to obtain some it should not have been difficult the

two chemists who had discovered the inert gases Lord Rayleigh and William Ramsay often worked together in the lab next door unfortunately Dewar had made enemies of both of them by publicly criticizing their science and belittling their achievements so they had no desire to share their helium kamilly olaf's was faced with the same problem as Dewar which is where can I get it supply of helium gas and he actually asked Dewar to try and collaborate with him to and Dewar said I'm having such a problem getting the gas by myself I can't possibly give you any

I'd like to but I can't eventually each found a supply but honest his industrial approach paid dividends after three years he had amassed enough helium gas to begin experiments The Tortoise was beginning to pull away from the hare the liquefaction of these gases had become a matter of enormous pride and prestige for Dewar but pretty quickly he ran out of resources he was reaching the limit of what the budget would bear at the Royal Institution and the helium supplies dried up one day when they were in the midst of working with gaseous helium an assistant

in Dewar clan turned a nod to the left instead of to the right a whole character of the gas escaped into the air and they had six months when they couldn't do any work whatsoever tor was furious at one point a doer writes to Camilla Honus telling telling him that he is not in the race anymore he thinks that the problems for liquify and helium are such that he's not able to complete the job the battlefields of science are the centres of a perpetual warfare in which there is no hope of a final victory to

serve and the scientific army to have shown the initiative is enough to satisfy the legitimate ambition of every earnest student of nature thank you in the summer of 1908 honors summoned his chief assistant flim from across the river they were finally ready to try to liquefy helium at 5:45 on July the 10th he assembled his team at the lab they had rehearsed the drill many times before Leyden was a small university town and the word quickly spread that this was the big day it took him to lunch time to make sure the apparatus was perched

at the last traces of air by 3:00 in the afternoon work was so intense that when his wife arrived with lunch he asked her to feed him so he didn't have to stop work this was a man obsessed at 6:30 in the evening the temperature began to drop below that of liquid hydrogen it's getting very late in the day and the team is down to its last bottle of hydrogen if they can't liquify helium now they're gonna have to wait for months to try again and the temperature gate is stuck at 5 degrees above absolute

zero and honest' doesn't know why this is and a colleague comes in and he suggests that that means maybe they've actually succeeded and they don't even know it yet so all it takes an electric lamp type thing and he goes underneath the operators and looks and sure enough there in the vial is this liquid sitting there quietly it's liquefied helium they had reached - 268 degrees centigrade just 5 degrees above absolute zero and finally produced liquid helium this monumental achievement eventually won honors the Nobel Prize when James Dewar heard that he had lost the race

to camel in honest it reacted a festering resentment doer berated his long-suffering assistant Lennox for failing to provide enough helium only this time Lennox had had enough he walked out of the Royal Institution vowing never to return until juror was dead and he kept his word for juror it was the end of his low-temperature research he must have been incredibly irritated and knowing juror he must one can imagine that sort of irritation he would have felt when onus came in for the Dutch to liquefy helium and even today owners his discovery of liquid helium is

seen as a much more significant discovery than jurors work on the Crafar hydrogen which is slightly unfair because all part of the process of trying to achieve absolute zero it remained that's very clear are wound in doors soul that never really healed I think that Dewar emerges at the end of the story as a rather tragic figure one of the very greatest late nineteenth-century British scientists who in the end is frustrated by a failure which hardly anybody could have expected him to achieve James jurors dream of reaching absolute zero was over he spent the rest

of his life investigating other scientific problems such as the physics of soap bubbles he had always been a loner ultimately his refusal to collaborate cost him the glory he felt he deserved I think it's really impressive how often scientists do seem to be driven by the spirit of competition by the spirit of getting there first but what's really fascinating about these races the race for absolute zero is that the goal posts move as you're playing the game the race in science is not for a predetermined end and once you're there the story is over the

curtain comes down that's not at all what it's like rather it turns out you find things you didn't expect nature is cunning as Einstein would have said and she is constantly posing a new challenge unanticipated by those people who start out on the race sometimes an unexpected event triggers a whole new area of research this happened in Leiden as Onassis team began to investigate how materials conduct electricity at these very low temperatures they observed that at around 4 degrees above absolute zero all resistance to the flow of electricity abruptly vanished Electrical resistant to drop as

if it had gone over a cliff it was going down and down and down and then it disappeared were all but disappeared and this was a first on a fishing thing nobody had ever seen anything like this before there was nothing on earth that had no electrical resistance honest later invented a new word to describe this bizarre phenomenon he called it superconductivity we have a circular ring of permanent magnets which are producing a magnetic field and now when we put a superconducting puck over it and give it a little push the magnetic field repels the

superconductor the magnetic field from the track induces a current in the supercooled puck which in turn creates an opposite magnetic field that makes the puck levitate it produces a magnetic field like a North Pole against North Pole and that's why you have the repulsion as the puck warms up its super conducting properties vanish along with its magnetically induced field four decades after its discovery in 1911 the underlying cause of superconductivity remained a mystery every major physicist every major theoretical physicist had his own theory of super conductivity everybody tried to solve it but it was unsuccessful

there were more surprises ahead in the 1930s another strange phenomenon was observed at even lower temperatures this rapidly evaporating liquid helium cools until at 2 degrees above absolute zero a dramatic transformation takes place suddenly you see that the bubbling stops and that the surface of the liquid helium is completely still the temperature is actually being lowered even further now but nothing particularly is happening well this this is really one of the great phenomenon in in 20th century physics the liquid helium had turned into a superfluid which displays some really odd properties here I have a

beaker with an unglazed ceramic bottom of ultrafine porosity ordinarily this container with tiny pores can hold liquid helium but the moment the helium turns superfluid it leaks through we call this kind of flow a super flow superfluid helium can do things we might have believed impossible it appears to defy gravity a thin film can climb walls and escape its container this is because a superfluid has zero viscosity it can even produce a frictionless fountain one that never stops flowing super fluidity and super conductivity were baffling concepts for scientists new radical theories were needed to explain

them in the 1920s quantum theory was emerging as the best hope of understanding these strange phenomena it's central idea was that atoms do not always behave like individual particles sometimes they merge together and behave like waves they can even be particles and waves at the same time this strange paradox was hard to accept even for great minds like Albert Einstein in 1925 a young Indian physicist sati Andhra Bose sent Einstein a paper he'd been unable to publish Bose had attempted to apply the mathematics of how light particles behave to whole atoms Einstein realized the importance

of this concept and did some further calculations he predicted that on reaching extremely low temperatures just a hair above absolute zero it might be possible to produce a new state of matter that followed quantum rules it would not be a solid or liquid or gas it was given a name almost as strange as its properties a bose-einstein condensate for the next 70 years people could only dream about making such a condensate matter can exist in various states atoms at high temperature always form gases if you cool the gas it becomes a liquid if you cool

the liquid it becomes a solid but under certain circumstances if you cool atoms far enough to extremely low temperatures they undergo a very strange transformation they undergo an identity crisis so let me show you what I mean by an identity crisis when you go to low temperatures the quantum mechanical properties of the atoms become important these are very strange very unfamiliar to us but in fact each one of these atoms starts to display wave-like properties so instead of points like that you have little wave packets like that moving around it's really difficult for me to

explain just why that is but that's the way it is now as you go to very low temperatures the size of these packets gets longer and longer and longer and then suddenly if you get them cold enough they start overlapping and when they overlap the system not like individual particles but particles which have lost their identity they all think they're everywhere this little wave packet over here can't tell it whether it's this one or that one or that one or that one or that one is there and it's there it's there they're all in one

great big quantum state they're all overlapping they're all doing the same thing and what they're doing to a good approximation is they're simply sitting at rest this bose-einstein condensate is very difficult to imagine or to visualize I could imagine what it's like to be an atom running around gaily freely bouncing into things sometimes going fast sometimes going slow but on the bose condensate i'm everywhere at once I've lost my identity I don't know who I am anymore I'm at rest and all the other atoms are round at rest but they're not other atoms around we're

all just one great big quantum system there's nothing else like that in physics and certainly not in human experience so just to think about this causes me wonder and confusion dan kleppner group at MIT began to try to make a bose-einstein condensate in hydrogen as we started out the search for bose-einstein condensation our enthusiasm grew because hydrogen seemed like such a wonderful atom to use it had everything going for it it had its light mass that means that the atoms will condense at a higher temperature than other atoms would the atoms interact with each other

very very weakly all the signals seem to be pointing to the fact that hydrogen was the atom for getting to bose-einstein condensation dan kleppner z' idea was to cool the hydrogen atoms by making use of their magnetic poles he used a strong magnetic field to create a cluster of atoms in a cold trap unfortunately sometimes one atom flipped another which triggered a release of energy that raised the temperature it was a frustrating time for us because our methods were so complicated we were having a hard time moving forwards it was time for the next generation

to have a go to scientists who trained in kleppner Department moved out west to Boulder Colorado they came up with a different approach to the problem rather than focusing on the lighter atoms of the periodic table Eric Cornell and Carl Wyman hit upon the idea of using much heavier metallic atoms like rubidium and cesium but would using these giants enable them to reach closer to absolute zero the idea in the field in those days was that the light things like hydrogen lithium would be easier and there are some good reasons for thinking that but we

had we had other ideas yeah sort of got intuition and some sense their plan was to use a laser beam to cool the atoms a technique that had already been tried at their old lab at MIT lasers are usually associated with making things hot but if they are tuned to the same frequency as atoms traveling at a particular speed they can make them cold when the stream of light particles from the laser hits the selected atoms in the gas cloud the atoms slow down and hence become cold laser cooling was a new tool that had

the potential to reduce the temperature of a gas to within a few millionths of a degree of absolute zero but Cornell and Wyman were not the only ones excited by this prospect a new scientist had arrived at MIT it was in late nineteen or early 92 that we had an idea an idea how a different arrangement of laser beams would be able to pool atoms to higher density and it worked and this was really a trigger point I will never forget the excitement in those oops whoop meetings when we discussed what will be next because

with higher density there are many things you can do could we now push to bose-einstein condensation kettle a used the full might of mi t--'s funding to build a laser lab to try to make a condensate in sodium atoms this is an atomic beam oven what is apt in tin foil is a little vacuum chamber where we heat up metallic sodium so the metallic sodium melts and evaporates and it's ultimately the sodium vapour the sodium atoms which we try to assign sign contains MIT Boulder and several other labs were chasing the same goal it had

echoes of the race to produce liquid helium almost a century earlier as I tell my students today anything worth doing is worth doing quickly because the science moves on and we're all mortal and you want to do things while MIT was installing expensive industrial lasers Carl Wyman had a different approach I threw out my experimental physics career I've always felt that technology played a big part so you could figure out a better technology for doing something it was going to pay off in the long run in physics in some cases he was ripping open old

fax machines and taking out the little chip inside that made the laser and show that you could take these lasers and put them into a home-built piece of apparatus stabilized the laser and use them to do spectroscopy and laser cooling this is actually our first what's called the vapor cell optical trap you can see it's kind of this old cruddy thing pulled together glass where we could send laser beams in from all the different directions and have just a little bit of the atoms we want to do cool as well as bombarding the atoms with

lasers they also trap them in a strong magnetic field you can have all your magnetic trap coils outside the vacuum system and again just a lot easier simpler to do everything we would try this sort of magnetic trap that sort of magnetic trap this sort of imaging that sort of imaging that sort of cooling all those things we could do without building a whole new chamber each time we tried literally four different magnetic traps in four years instead of having a three or four year construction project for each one by being fast and flexible the

boulder group hoped to beat their old lab at MIT and MIT had its own plans this was a prize they felt should be theirs there was a sense of competition but it was what I would call friendly complication I mean can you imagine two athletes they are in the same training camps they help each other they even give tips to each other but then when it comes to the race everybody wants to be the first the rival groups were all using magnetic trapping and laser cooling to cool their atoms but for the final push towards

absolute zero to turn these atoms of gas into the quantum state Einstein had predicted they needed one more cooling technique evaporative cooling it's just like with this coffee the steam coming off the coffee is the hottest of the coffee molecules escaping and carrying away more than their fair share of energy in the case of the atoms we keep the atoms in a sort of magnetic Bowl and we confine the atoms there they zoom around inside the bowl and then the hottest ones have enough energy to roll up the side of the bowl and fall over

the edge slop over the edge taking away with them much more than their fair share of energy and the atoms that remain have less and less energy which means they move slower and slower and start to cluster near the bottom and as that happens we gradually lower the edges of the magnetic trap and always so there's just a few items that can escape until finally the remaining atoms clustered near the bottom of the bowl huddled together they get colder and colder and denser and denser and eventually in this way of apparation forces the bose-einstein condensation

to occur one problem that we kept encountering is that we had to keep the atoms isolated from the walls we had to have a really good vacuum and yet if the vacuum is perfect what is it that you're actually working with we had to have a little bit of rubidium gas in there a tiny bit of rubidium gas that we could catch a catch with our lasers and slow down so we had this wild idea of changing constantly changing the pressure in the in the chamber letting the pressure get higher and lower and we built

the very elaborate chamber with valves that opened and closed and and the pumps that turned on and off and it didn't work for beans I mean we spent six months wasted I might say six months on valves opening closing pumps turning on and off the problem is the rubidium gas has a little bit of stickiness to it and that meant while we were trying to get all the rubidium out of there that residual gas was heating up the atoms so eventually we had to give up on that idea by now the race to produce a

bose-einstein condensate was intensifying at every major meeting every canal and I gave talks or talk to each other with a keenly aware that we were both working towards the same goal it's a mixed it's a mixed thing on the one hand it's it's flattering because they're using an approach which we had pioneered and we felt good about that on the other hand it was made us a little nervous because hmm we want to advance knowledge but science is a competitive business and we wanted to be felt that we wanted to do it first and maybe

that we were entitled to do it first although even that's a mixed bag because after all we had jumped into the game of the hydrogen people who had shown us so many of the tricks over the years at one point during that period I'm ever Karl Wyman being quoted in an article saying that he hopes that the MIT group gets there first because they started at all and so they would get the Nobel Prize and then the Jilla group could do all the interesting science well there was a very nice thought didn't quite work out

that way in June 1995 the bolder group was working round the clock knowing that several other labs were also poised to produce the first condensate an official visit from a government funding committee was the last thing they needed the standard thing you do when the important people come around as you close down your lab and clean up everything and put posters on the walls they can see how productive you are of course that's the exact opposite of being productive we didn't want to close down the lab or clean up our lab report posters we wanted

to work very hard so the senior dignitaries in the three-piece suits and so on came in to the lab and we left the lights off and everyone continued to work and I made them keep their voices down and talk to them rather in a hurried way and then sort of shuffled them out the door and they all had a slightly puzzled look on their face because it probably had never happened to them before in the history of being a visiting committee that they were treated with his little little pomp and later I actually met one

of the guys who said I suspected something up was up that day because otherwise you never would have dared to do that June the 5th 1995 turned out to be a big day in the history of physics they had finally made what Einstein had predicted 70 years before a bose-einstein condensate our first reaction was wait we got to be careful here you know we let's think of all the different knobs we can turn checks we can make and so on to see if this really is bose-einstein condensation a condensate is sort of like a vampire

if the sunlight even once falls on it it's dead and so it's it's realm as the realm of the dark but we can take pictures of them because we strobe the laser light really fast and even as the condensate dying it cast a shadow and the shadow is frozen in in the film Wyman and Cornell created the first bose-einstein condensate in a cloud of just three thousand atoms of rubidium the first in the universe as far as we know they had reached a temperature of 170 billions of a degree above absolute zero one of the

first things you need to understand about bose-einstein condensation is how very very cold it is um where we live at room temperature is far above absolute zero on this scale imagine that room temperature is represented by London thousands of kilometres from here then on that scale if we imagine right here where I'm standing in Boulder is absolute zero the coldest possible temperature then how close are we to absolute zero if we think of London as being room temperature and right where I am is absolute zero then bose-einstein condensation occurs just the thickness of this pencil

led away from absolute zero within weeks of the boulder group success Wolfgang ketterle produced an even larger condensate from 10 million sodium atoms at last quantum mechanics with more than just theoretical mumbo-jumbo it was something that could be seen with the naked eye Wyman Cornell and kettle a shared the Nobel Prize for Physics in 2001 one of the things Nobel Prize means and the ceremony means it it everybody remembers Eric's the person who forgot to bow to the king there was a breakdown of protocol on my part there is no excuse because they actually drill

us - it's more like our you have a series of rehearsals practicing how to bow to the king and I somehow managed to bollocks it up at the last possible moment and I thought maybe you know Karl who came after me would do this make the same mistake and then no one would figure it out but now he was perfect I heard about the Nobel Prize when I was woken up by a telephone call which was it I think 5:30 in the morning so you wake up you go to the telephone and somebody tells you

congratulations you've won the Nobel Prize you're still tired your brain is not fully functional but you realize this is vegans and what you feel listen you know pride pride for MIT your collaborators for yourself it's wonderful to see that your work gets recognized and acknowledged in this way like any great adventure the pursuit of science offers no guarantee of success but for the godfather of ultra cold atoms persistence eventually paid off after 20 years of struggling to obtain a condensate in hydrogen dan kleppner finally succeeded for a few fleeting moments his dream came true of

course we were delighted I think everyone was delighted because we've been working on it for so long it's kind of embarrassing to have this group would help start the workers working away their fruitlessly while everyone was enjoying success when we got it everyone was happy to see that an effort which lasted for 20 years which took so much patience frustration and tenacity to see that succeed is just emotional it's liberating I will never forget this standing ovation which then kleppner received at the Ravenna summer school when he announced bose-einstein condensation hi gosh everybody just got

up and gave it was sort of like an opera where everybody's cheered and people were crying and because everybody realized that they had they had finished the race but too late and and it wasn't going to work out but in some sense they had really stimulated the whole field so it was very very moving very moving moment for the pioneers who had realized Einsteins dream and created condensates it was the end of an extraordinary decade of physics now there was a new challenge to work out what to do with them at Harvard a Danish scientist

Lena how had the idea of using a condensate to slow down light we all have this sense you know light is something that nothing goes faster than light in vacuum and if somehow we could use a system to get light down to you know added to a human level I thought that was just absolutely fascinating it is actually very odd it's also extremely or to a lot of my colleagues Lena how created a cigar-shaped bose-einstein condensate to carry out her experiment she fired a light pulse into the cloud the speed of light is around a

billion kilometres per hour but when the pulse hits the condensate it slows down to the speed of a bicycle so light pulse might start out being one to two miles long in free space it goes into our medium and since the front edge sensors first that will slow down the baguettes is still in free space that'll catch up and then create that compression and it'll end up being compressed from one to two miles down to 0.0001 micron or even smaller than that you could say well gee is this to stop light because I could just

set a laser beam into a wall and I would stop it well the problem is you lose the information because it's so named so heat you can navigate that information back in our case when we start with the information is not lost because that's stored in the medium and anyone we are time to revive it the system has all the information to revive the light parts and you can move on one day ultra cold atoms will probably be used to process information but quite how is hard to predict sometimes the promised benefits from a scientific

breakthrough take a long time to emerge many predicted that by this century energy savings superconducting power lines and maglev bullet trains would be Criss crossing the continents perhaps now as world energy supplies dwindle these technologies once seen as an economic will start to take off now it is the quantum nature of the cold frontier that has captured imaginations supercooled quantum devices are mapping the magnetic activity of the brain and cold atoms are being turned into quantum computers as a quantum mechanic I engineer atoms to make a computer out of atoms you have to somehow get

atoms to register information and then to process it why why build quantum computers because they're cool it's fun and we can do it right I mean we actually can take atoms and if we ask them nicely they'll compute that's a lot of fun I mean have you ever talked to an atom recently and had it talk back it's great you know learn to speak atom and the atom speak back that's great quantum world is is in the world of the very small it's like an exotic wilderness that you've never been in before and things you

wander in and everything looks strange and you see things that you've never seen but if you really want to see what's going on then you've got to be quiet so if you go into the wilderness and you're going mad about it up above the ball then you're never going to see things because all these exotic phenomena are going to know that you're there and they're going to stay put and they're not going to come out so if you make a lot of noise that's bad now at the quantum level at the microscopic level heat is

noise so if you want to see these strange and exotic effects you have to be quiet very quiet there can't be a lot of noise and that means you have to cool things down yes look at that that's beautiful unlike ordinary computers where each decision is based around a bit of information and is either a 0 or a 1 in the quantum world the rules change at first glance a quantum computer looks almost exactly the same but quantum mechanics is weird it's funky ok it's weird when you do quantum computer you want to make this

weirdness work for you so now let's look at our quantum bit or qubit the qubit can not only be a 0 or 1 and also both be a 0 and 1 at the same time it's almost like a form of America in a world but an apparently computer quantum one processor does this one classes as that so that two processors doing this in that quantum computer is doing a many many processors install isn't and that at the same time looks like it's more the turning within the giant Dewar flask lies a prototype quantum computer surrounded

by its supercooled superconducting magnet in the future quantum computing could be used to predict quantum interactions such as how a new drug acts on faulty biochemistry or to solve complex encryption problems like decoding prime numbers that are the key to internet credit card security this weird quantum world is part of a new frontier opened up by the descent towards absolute zero it's been a remarkable journey for scientists into unknown territories far beyond the narrow confines of earth on the Kelvin temperature scale which begins at zero degrees for absolute zero the temperature of the Sun is

around five thousand degrees at 1000 degrees metals melt at 300 degrees we reach what we think of as room temperature air liquefies at a hundred degrees hydrogen at 20 degrees helium at four degrees the deepest outer space is three degrees above absolute zero the coldest place outside the laboratory but the descent doesn't stop there with ultra cold refrigerators the decimal point shifts three places to a few thousandths of a degree and laser cooling takes it down three more places to a millionth of a degree the temperature of a bose-einstein condensate with magnetic cooling we shift

four more decimal places until we reach the coldest recorded temperature in the universe at a lab in Helsinki one hundred pico kelvin or a tenth of a billionth of a degree above absolute zero so will it ever be possible to go all the way to reach the holy grail of cold zero degrees getting to absolute zero is tough nobody's actually been there at absolute zero point zero zero zero zero zero zero with an infinite number of zeros that last little tiny bit of heat becomes harder and harder to get out and in particular the timescales

for getting it out get longer and longer and longer the smaller and smaller the amounts of energy involved so eventually if you're talking about extracting an amount of energy that's sufficiently small it would indeed take the age of the universe to do it all so you actually need an apparatus the size of the universe to do it but that's another story absolute zero maybe unreachable but by exploring further and further towards this ultimate destination of cold many fundamental secrets of matter have been revealed if our past was defined by our mastery of heat perhaps our

future lies in the continuing conquest of coal on Thursday at 9:00 on bbc4 science you can't see series continues with that tiniest of keys to the biggest of questions the atom the Marley brothers are jamming live at Glastonbury next