Absolute Zero ✪ PBS Nova Documentary Channel

Summary

The PBS Nova documentary "Absolute Zero" explores humanity's ongoing quest to understand and harness the mysterious force of cold. From the early misconceptions of cold as a malevolent force to its modern-day application in technology and science, this documentary traces the journey of scientists who ventured into the coldest realms. It covers the historical efforts to conquer cold, from refrigeration to air conditioning, and highlights the groundbreaking advances towards achieving absolute zero. The documentary also delves into the modern technological breakthroughs made possible by ultra-cold temperatures, including superconductivity, superfluidity, and quantum computing, illustrating the profound impact cold has had on civilization.

Highlights

• Discover how cold went from being a feared element to a revolutionizing tool. ❄️
• Learn about historical figures who contributed to our understanding of cold. 📚
• Understand how refrigeration and air conditioning changed industries and daily life. 🏭
• See how scientists tread closer to absolute zero, breaking new grounds in physics. 🔬
• Dive into how ultra-cold temperatures pave the way for quantum advances. ⚛️

Key Takeaways

• Cold is just as significant as heat in advancing civilization's technology. ❄️
• The conquest of cold revolutionized food preservation and the industrial world. 🧊
• Superconductivity and superfluidity opened new frontiers in physics. 🧪
• Quantum computing is the next frontier, made possible by ultra-cold temperatures. 💻
• Absolute zero remains an unattainable yet pursued scientific milestone. 🚀

Overview

The documentary begins with the historical context, highlighting humanity's early misconceptions about cold as a fearful, misunderstood force. It was seen as malevolent, but slowly turned into a field of scientific inquiry by pioneers who sought to control it for practical benefits like refrigeration and air conditioning, drastically changing daily life and urban landscapes.

As the narrative progresses, the documentary delves into the fascinating race toward the colder side, exploring liquefying gases and the heroics of scientists striving to reach the coldest temperatures possible. It captures the competitive spirit of scientists and the quest for mastery over nature’s coldest extremes, which leads to new phenomenon discoveries such as superconductivity and superfluidity.

In its closing, "Absolute Zero" highlights the modern frontiers of ultra-cold physics, focusing on how these temperatures challenge our understanding of physics and open doors to advanced technologies like quantum computing. Despite never reaching absolute zero, this pursuit highlights the ongoing dedication and curiosity driving scientific discovery forward.

Chapters

• 00:00 - 10:00: Introduction: The Mystery and Conquest of Cold The introduction sets the stage for exploring humanity's journey in understanding and overcoming cold. It contrasts the common emphasis on the mastery of heat with the often-overlooked conquest of cold, describing it as an epic journey starting from mysterious beginnings to advanced scientific achievements.
• 10:00 - 20:00: The Science of Cold in the 17th and 18th Centuries The chapter discusses the transformative impact of cold technology developed during the 17th and 18th centuries. It highlights that in the past century, innovations in refrigeration, air conditioning, MRI machines, and liquid oxygen have drastically changed everyday life, from supermarkets to hospitals. These advancements not only improved daily living conditions but also enabled significant achievements such as space exploration and advanced medical diagnostics.
• 20:00 - 30:00: Revolutionizing Cold: Industrialization and the Thermodynamic Breakthrough In this chapter, the focus is on the revolutionary advancements in ultra-cold technology. The narrative explores how industrialization and breakthroughs in thermodynamics have enabled the development of quantum computers and high-speed networks. The chapter delves into the historical fear and eventual conquest of controlling extreme cold temperatures, showcasing the relentless pursuit by scientists and innovators over the past four centuries to push the boundaries of what was once deemed terrifying and unapproachable.
• 30:00 - 40:00: The 19th Century Ice Trade and Artificial Refrigeration The chapter explores the 19th-century innovation of the ice trade and the emergence of artificial refrigeration. It discusses the historical quest to understand and manipulate cold temperatures, and the endeavors to achieve absolute zero, which is considered the ultimate temperature. It also mentions the cultural and scientific significance of these advancements.
• 40:00 - 50:00: The Impact of Refrigeration and Air Conditioning on Modern Life The chapter explores the historical perception of extreme cold, which has long been seen as a threatening force linked with death and darkness.
• 50:00 - 60:00: The Race to Absolute Zero: Liquefying Permanent Gases The chapter "The Race to Absolute Zero: Liquefying Permanent Gases" begins by reflecting on the enigmatic nature of cold in the 17th century. During this period, known as the Little Ice Age, England experienced severe cold weather, making cold seem like an actual presence or force. It was a time when understanding weather phenomena was limited, leaving people in constant cold, which was pervasive and inescapable, as they lived in a world lit by fire yet still persistently cold. The text invites the reader to imagine these stark conditions as it sets the stage for exploring the scientific quest to comprehend and manipulate cold temperatures.
• 60:00 - 70:00: 20th Century Physics: Superconductivity and Superfluidity The chapter discusses the early perceptions of cold and natural forces, which were often seen as acts of God. It highlights the dangers perceived by those who attempted to manipulate cold, beginning with the alchemist Cornelius Dreel in 1620.
• 70:00 - 80:00: The Quantum Era: Bose-Einstein Condensates and Beyond The chapter titled 'The Quantum Era: Bose-Einstein Condensates and Beyond' delves into a historical event where King James I and his court magician, Trebble, engage in a fascinating experiment. Trebble wagers he can manipulate the seasons by turning summer into winter. To achieve this, he plans to chill the air in the Great Hall of Westminster, which was noted as the largest interior space in the British Isles at the time. This intriguing venture aims to impress and possibly bewilder the king.
• 80:00 - 90:00: Ultra-Cold Frontiers: Current and Future Innovations This chapter introduces an individual with a highly inventive and fertile mind, deeply engaged in the realms of alchemy, perpetual motion, and the metaphysical concepts of time and space. The narrative touches upon his complex worldview, one that balances fervent religious beliefs with a profound respect for the natural world's boundless possibilities.
• 90:00 - 100:00: Conclusion: The Continuing Conquest of Cold Dr. Andrew Shidlo, a chemist with a passionate interest in Dreel, revels in his role as the great Court magician. Like many alchemists, Dreel kept his methods confidential. Dr. Shidlo is eager to experiment with and verify his theories on Dreel's creation of artificial cold, especially during Dreel's attempts to reach the lowest possible temperatures.

Absolute Zero ✪ PBS Nova Documentary Channel Transcription

• 00:00 - 00:30 [Music] when you support your local PBS station you help make programs like this one [Music] possible the greatest Triumph of civilization is often seen as our Mastery of heat yet our conquest of cold is an equally Epic Journey from dark beginnings to an Ultra Cool Frontier for centuries cold remained a perplexing mystery with no obvious
• 00:30 - 01:00 practical benefits yet in the last 100 years cold has transformed the way we live and work imagine supermarkets without Refrigeration skyscrapers without air conditioning hospitals without MRI machines and liquid oxygen we take for granted the technology of coal yet it has enabled us to explore outer space and the inner
• 01:00 - 01:30 depths of our brain and as we develop new Ultra cold technology to create quantum computers and high-speed networks it will change the way we work and interact how did we harness something once considered too fearsome to even investigate how have scientists and dreamers over the past four centuries plunged lower and lower down the
• 01:30 - 02:00 temperature scale to conquer the cold and reach its ultimate limit a Holy Grail as elusive as the speed limit of light absolute zero up next on [Music] Nova
• 02:00 - 02:30 [Music] extreme cold has always held a special place in our imagination for thousands of years it seemed like a malevolent Force associated with death and darkness cold was an un explained
• 02:30 - 03:00 phenomenon was it a substance a process or some special state of being back in the 17th century no one knew but they certainly felt its effects in the freezing London Winters 17th century England was in the middle of what's now called the little Ice Age it was fantastically cold by modern standards you have to imagine a world lit by fire in which most people are cold most of the time cold would have felt like a real presence a kind of
• 03:00 - 03:30 positive agent that was affecting how people felt back then people felt at the mercy of cold this was a time when such natural forces were viewed with awe as acts of God so anyone attempting to tamper with cold did so at his Peril the first to try was an alchemist Cornelius dreel on a hot summer day in 1620 King
• 03:30 - 04:00 James I and his Entourage arrived to experience an unearthly event trebble who was also the court magician had a wager with the King that he could turn summer into winter he would attempt to chill the air in the largest interior space in the British Isles the Great Hall of Westminster dreel hope to shake the king
• 04:00 - 04:30 to his core he had a phenomenally fertile mind he was an inventor par Excellence his whole world was steeped in a world of alchemy of Perpetual Motion Machines of the idea of time space planets Moon Sun Gods he was a fervently religious man he was a a person for whom nature presented a phenomenal a galaxy of possibility
• 04:30 - 05:00 Dr Andrew shidlo a chemist with a lifelong Fascination for dreel enjoys his reincarnation as the great Court magician like most Alchemists dreel kept his method secret Dr shidlo wants to test his ideas on how dreel created artificial [Music] cold when dble was trying to achieve the lowest temperature possible he knew the
• 05:00 - 05:30 ice of course was the freezing point the coldest you could get normally but he would have been aware of the fact through his experience that mixing ice with different salts could get you a colder temperature salt will lower the temperature at which ice melts Dr shidow thinks dreel probably used common table salt which gives the biggest temperature drop but salt and ice alone would not be enough to cool the air within such a large
• 05:30 - 06:00 interior dreel was famous for Designing elaborate Contraptions a passion shared by Dr shidlo Who has an idea for the alchemist's machine so here we would have had um a fan which would have been turned over blowing warm air over the cold vessels there and as the air blows over these cold jars we would have had in effect the world's first air conditioning
• 06:00 - 06:30 unit but could this really turn summer into winter the idea was to stir it in as well as possible in in five in the 5 Seconds that you have to do it Dr shidlo Stacks the jars of freezing mixture to create cold corridors for the air to pass through right we can feel it's very cold and the in fact I could feel cold air
• 06:30 - 07:00 actually falling on my hands because cold air of course is denser than warm air and one can feel it quite clearly on the [Applause] fingers the vital question would the gust of warm air become cold woof I can feel certainly a blast of cold air hitting me as that second cover was released least well
• 07:00 - 07:30 temperature with we're on 14 at the moment yes keep it going that's definitely the right direction King James would have been shaken by his encounter with man-made cold had dreel written up his great stunt he might have gone down in history as the inventor of air conditioning yet it would be almost three centuries before this idea would actually take off
• 07:30 - 08:00 to advance knowledge and conquer the cold required a very different approach the scientific method the fundamental question what is cold haunted Robert Bole nearly 50 years later the son of the Earl of cork a wealthy nobleman Bole used his fortune to build an extensive Laboratory Bole is famous for his
• 08:00 - 08:30 experiments on the nature of air but he also became the first master of cold believing it to be an important but neglected subject he carried out hundreds of experiments he worked through very systematically a series of ideas about what cold is does it come from the air does it come from the absence of light is it that there are strange so-called
• 08:30 - 09:00 frigorific cold making particles in Bo's day the dominant view was that cold is a primordial substance that body in as they get and expel as they warm up it was this view that boil would eventually overturn by a set of carefully devised experiments on water
• 09:00 - 09:30 first he carefully weighed a barrel of water and took it outside in the snow leaving it to freeze overnight Bole was curious about the way water expanded when it turned to ice he reasoned that if once the water turned to ice the barrel weighed more then perhaps cold was a substance after all but when they reweighed the barrel they discovered it weighed exactly the
• 09:30 - 10:00 same so what must be happening boil guess was that the particles of water were moving further apart that was the expansion not some substance flowing into the barrel from outside boil was becoming increasingly convinced that cold was not a substance but something that was happening to individual particles and he began to think back to his
• 10:00 - 10:30 earlier experiments with air as matter like air becomes warmer it tends to expand Bo imagine the air particles were like tiny Springs gradually unwinding and taking up more space as they heat up Bo's conclusion here was that heat is a form of motion of a particular kind and that as bodies cool down they move
• 10:30 - 11:00 less and less Bo's longest published book was on the cold yet he found its study Troublesome and full of hardships declaring that he felt like a physician trying to work in a remote country without the benefit of instruments or medicines to properly explore this country of the cold Bole lamented the lack of a vital tool an accurate
• 11:00 - 11:30 [Music] thermometer it was not until the mid 17th century that glass blowers in Florence began to produce accurately calibrated thermometers now it became possible to measure degrees of hot and cold like the air in Bo's experiment heat
• 11:30 - 12:00 makes most substances expand early thermometers used alcohol which is lighter than Mercury and expands much more with heat so these Florentine thermometers were sometimes several meters long and often wound into spirals but there was still one major problem with all thermometers the lack of a universally accepted temperature scale there are all kinds of different ways of
• 12:00 - 12:30 trying to stick numbers to these degrees of hot and cold and they on the whole didn't agree with each other at all so one guy and Florence makes one kind of thermometer another guy in London makes a different kind and they just don't even have the same scale and so there was a lot of problem in trying to standardize thermometers the challenge was to find events in nature that always occur at
• 12:30 - 13:00 the same temperature and make them fixed points at the lower end of the scale that might be ice just as it begins to melt at the upper end it could be wax heated to its melting point the first temperature scale to be widely adopted was devised by Gabriel Daniel Fahrenheit A Gifted instrument maker who made thermometers for scientists and Physicians across Europe
• 13:00 - 13:30 he had several fixed points he used a mixture of ice water and salt for his 0 deg ice melting in water at 32° and for his upper fixed point the temperature of the human body at 96° which is close to the modern value one of the things that Fahrenheit was able to achieve was to make thers quite small and that he did by using mercury as as opposed to alcohol or air
• 13:30 - 14:00 which um other people had used and because Merc the moment there's a compact um clearly if you're trying to use it for clinical purposes you don't want some big thing sticking out of the patient so um the fact that he could make them small and convenient that seems to be what made Fahrenheit so famous and so influencer it was a Swedish astronomer Anders Celsius who came up with the idea of dividing the scale between two fixed
• 14:00 - 14:30 points into 100 divisions the original scale used by Celsius was upside down so he had the boiling point of water as zero and the freezing point as 100 with numbers just continuing to increase as we go below freezing and this is another little mystery in the history of the thermometer that we just don't know for sure what was he thinking when he
• 14:30 - 15:00 labeled it this way and it was the botanist Lenas um who was then the president of the Swedish Academy who after a few years said we need to stop this nonsense and inverted the scale to give us what we now call Celsius scale today a question nobody thought to ask when devising temperature scales was How Low Can You Go is there an absolute
• 15:00 - 15:30 lower limit of temperature the idea that there might be would become a turning point in the history of cold The Story begins with the French physicist giio M pressure he was doing experiments uh Heating and Cooling bodies of air to see how they expand and contract am Monon heated air in a glass bulb by placing it in hot
• 15:30 - 16:00 water just like a hot air balloon the air in the glass bulb expanded as the increased pressure forced a column of mercury up the tube then he tried cooling the air he was noticing that well when you cool a body of air the pressure would go down and he speculated well what would happen if we just kept cooling it by plotting this falling temperature
• 16:00 - 16:30 against pressure amonton saw that as the temperature dropped so did the pressure and this gave him an extraordinary idea amonton started to consider the possibility what would happen if you projected this line back until the pressure was zero and this was the first time in this course of history that people had actually considered the concept of an absolute zero of temperature zero pressure zero temperature it was quite a
• 16:30 - 17:00 revolutionary idea when you think about it because you wouldn't just think that temperature has a limit of a lower bound or zero because in the upper end it can go on forever we think until it's hotter and hotter and hotter but somehow maybe there's a zero point where this all begins so you could actually give a calculation of where this um zero point
• 17:00 - 17:30 would be am monong didn't do that calculation himself but some other people did later on and when you do it you get a value that's actually not that far from the modern value of roughly minus 273 CRA in one stroke amonton had realized that although temperatures might go on Rising forever they could only fall as far as this absolute point now known to be minus 2 273°
• 17:30 - 18:00 Centigrade for him this was a theoretical limit not a goal to attempt to reach before scientists could Venture towards this zero point far beyond the coldest temperatures on Earth they needed to resolve a fundamental question by now most scientists defined cold simply as the absence of heat but what was actually happening as substances warmed or or cooled was still
• 18:00 - 18:30 hotly debated the argument of men like amont relied completely on the idea that heat is a form of motion and that particles move more and more closely together as the substance in which there in get gets cooler and cooler unfortunately the science of cold was about to suffer a serious setback the idea that cooling was caused by particles slowing down began to go out out of
• 18:30 - 19:00 fashion at the end of the 18th century a rival theory of heat and cold emerged that was tantalizingly appealing but completely wrong it was called the caloric Theory and its principal Advocate was the great French chemist antoan Lavoisier like most scientists of the time Lavoisier was a rich Aristocrat who who funded his own research he and his
• 19:00 - 19:30 wife Madame Lavoisier who assisted with his experiments even commissioned the celebrated painter David to paint their portrait leazier carried out experiments to support the erronous idea that heat was a substance a weightless fluid that he called caloric he thought in the solid state of matter molecules were just packed close in together and when you added more and
• 19:30 - 20:00 more caloric to this uh the caloric could insinuate itself between these particles of matter and loosen them up so the basic notion was that caloric was this fluid that was as you put it self repulsive it just tended to break things apart from each other and that's his basic notion of heat so cold is just the absence of chorine or the relative lack of
• 20:00 - 20:30 caloric Lavoisier even had an apparatus to measure caloric which he called a calorimeter he packed the outer compartment with ice inside he conducted experiment that generated heat sometimes from chemical reactions sometimes from animals to determine how much caloric was released he collected the water from the melting ice and weighed it to calc calculate the amount of caloric generated from each
• 20:30 - 21:00 Source I think the most striking thing about leier is that he sees caloric as a substance which is exactly comparable with ordinary matter to the point that he includes goric in his list of the elements indeed for lavasier it's an element Like Oxygen or nitrogen oxygen gas is made of oxygen plus caloric and if you take the caloric
• 21:00 - 21:30 away presumably the oxygen might liquefy so it's a very hard model to shift because it explains so much and indeed lavoisier's chemistry was so otherwise extraordinarily successful however lavoisier's story about ceric was soon undermined but there was one man who was convinced leiser was wrong and was determined to to destroy the caloric
• 21:30 - 22:00 Theory his name was count [Music] Rumford count Rumford had a colorful past he was born in America spied for the British during the revolution and after being forced into Exile became an influential government minister in Bavaria among his varied responsibilities was the artillery works and it was here in the 1790s that
• 22:00 - 22:30 he began to think about how he might be able to disprove the caloric Theory using cannon boring Rumford had noticed that the friction from boring out a cannon Barrel generated a lot of heat he decided to carry out experiments to measure how much he adapted the machine to produce even more heat by installing a blunt borer that had one end submerged in a
• 22:30 - 23:00 jacket of water as the cannon turned against the borer the temperature of the water increased and eventually boiled the longer he bored the more heat was produced for Rumford what this showed was that heat must be a form of motion and heat is not a substance because you could generate indefinitely large amounts of heat simply by turning the
• 23:00 - 23:30 cannon despite count rumford's best efforts leiser's caloric Theory remained dominant until the end of the 18th century his Prestige as a chemist meant that few dared challenge his ideas but this did not protect him from the Revolutionary turmoil in France which was about to interrupt his research at the height of the reign of terror laiser was arrested and eventually lost his
• 23:30 - 24:00 head once he was guillotined his wife left France and uh eventually met Rumford when he moved to Western Europe in the early 1800s Rumford then married her so he'd married the Widow of the man who'd founded the theory that he'd destroyed the marriage was shortlived after a tormented year Rumford left Madame laiser and devoted the rest of his life to his his first love
• 24:00 - 24:30 science it would be nearly 50 years before rumford's idea that temperature is simply a measure of the movement of particles was accepted with heat the particles what we now know as atoms speed up and with cold they slow down rumford's dedication to science led him to become a founder of the Royal Institution in London and it was here
• 24:30 - 25:00 that the next major breakthrough in the conquest of cold would occur Michael Faraday who later became famous for his work on electricity and magnetism would take a critical early step in the long descent towards absolute zero when he was asked to investigate the properties of chlorine using crystals of chlorine hydrate this experiment was potentially explosive which is perhaps why it was left to Faraday and perhaps also why Dr
• 25:00 - 25:30 Andrew shidlo is curious to repeat it today we are about to undertake an exceedingly dangerous experiment in which Michael Faraday in 1823 heated this substance here the hydrate of chlorine in a sealed tube is that sealed that's sealed Andrew that's absolutely brilliant in in the original experiment Faraday took the sealed tube and heated
• 25:30 - 26:00 the end containing the chlorine hydrate in hot water he put the other end in an ice bath soon he noticed yellow chlorine gas being given off because the gas is being produced pressure is building up Ray this is where it starts to get dangerous so if you now take a few steps back when Faraday did the experiment a
• 26:00 - 26:30 visitor Dr Paris came by to see what he was up to Paris pointed out some oily matter in the bottom of the tube Faraday was curious and decided to break open the tube right so let's have a look inside [Applause] here the explosion sent shards of glass flying with a sudden release of pressure the oily liquid
• 26:30 - 27:00 vanished and there we are is that what happened yeah that's exactly what happened it popped Open Glass flew and can you detect the strong smell of chlorine can now absolutely well he detected the strong smell of chlorine and this um this was a major mystery for him Faraday soon realized the increased pressure inside the sealed tube tube had caused the gas to
• 27:00 - 27:30 liquefy and when the tube was broken the oily liquid evaporated just as heat must be applied to evaporate water he saw that energy from the surrounding air had transformed liquid chlorine into a gas in a brilliant deduction farad realized that by absorbing heat from the air he had cooled or refrigerated the surroundings Michael Farris day had produced
• 27:30 - 28:00 cold later he used the same technique with ammonia which absorbs even more heat he predicted that one day this cooling might be commercially [Music] useful Faraday took no interest in commercial exploitation but across the Atlantic a Yankee entrepreneur had a very different philosophy Frederick Tudor had a chance
• 28:00 - 28:30 conversation with his brother that led him on a path to become one of the richest men in [Music] America The Story Goes at the dinner table they were trying to decide what they had on their Father's Farm they could make money off of and certainly there was a lot a lot of rocks but people weren't going to pay for that so they came up with the idea of maybe ice cuz some areas did not have ice and it seemed kind of crazy at first but uh it
• 28:30 - 29:00 paid off when tutor began harvesting ice from New England ponds he soon realized he needed specialized tools to keep up with the huge demand we had the saws and the saws were a improvement over the old wood saws they have teeth that are sharpened on both sides and set so it cuts on both the up and the down stroke and a crew could clear a 3 Acre Pond
• 29:00 - 29:30 easily in a couple of [Music] days jer's dream to make ice available to all was not confined to New England he wanted to ship ice to hot parts of the world like the Caribbean and the Deep South when tutor first tried to convince ship Masters to put his load of Frozen water into the ships uh they all refused cuz they told him that water belonged
• 29:30 - 30:00 outside the hole not inside so he had to go find other investors to uh get the money to buy his own ship and he bought a ship by the name of the favorite New England became the refrigerator for the world with ice shipments to the Caribbean the coast of South America and Europe tutor even reached India and China watching ing the ice Cutters working Walden Pond Henry thorough
• 30:00 - 30:30 marveled that water from his bathing Beach was traveling Halfway Around the Globe to end up in the cup of an East Indian philosopher tutor who soon became known as the Ice King began using horses and huge teams of workers to harvest larger and larger Lakes as the demand for ice grew during the latter half of the 19th centur the ice industry eventually employed
• 30:30 - 31:00 tens of thousands of people tutor became the largest distributor of of ice and he became one of the first American Millionaires and we're talking about one of his ships going to the Caribbean giving him a profit of $6,000 now this is in a time period when people were earning $2 to $300 a year the average family so someone earning thousands of dollars was just
• 31:00 - 31:30 inconceivable and that would be losing 20% of your your ice when it got there there was still huge amounts of profit tutter's success was based on an extraordinary physical property of ice it takes the same amount of heat to melt a block of ice as it does to heat an equivalent quantity of water to around 80° C this meant that ice took a long time to melt even when when shipped to hotter
• 31:30 - 32:00 climates what started out as a small family Enterprise turned into a global business Frederick tutor had industrialized cold in the same way the great pioneers of steam had harnessed [Music] Heat by the 1830s the industrial re Revolution was in full swing yet ironically it was not until a
• 32:00 - 32:30 small group of scientists worked out the underlying principles of how steam engines convert heat into motion that the next step in the conquest of cold could be made only after solving this riddle of heat engines could the first cold engines be made to produce artificial [Music] Refrigeration how much useful work can you get out of a given amount of heat by
• 32:30 - 33:00 the early 1800s that had become the single most important economic problem in Europe to make a profit was to convert heat into motion efficiently without wasting heat and getting the maximum amount of mechanical effect
• 33:00 - 33:30 the first person to really engage with this problem was a young French artillery engineer Sadi Carno he thought that improving the efficiency of steam engines might help France's flagging economy after defeat at waterl in 1815 working at the conservat Des Art he began to analyze how a steam engine was able to turn heat into mechanical work in Steam Engines it looks as though heat
• 33:30 - 34:00 is Flowing around the engine and as it flows the engine does mechanical work the implication there is that heat is neither consumed nor destroyed you simply circulate it around and it does work Carno likened this flow of of heat to the flow of water over a water
• 34:00 - 34:30 wheel he saw that the amount of mechanical work produced depended on how far the water fell his novel idea was that steam engines worked in a similar way except this fall was a fall in temperature from the hottest to the coldest part of the engine the greater the temperature difference the more work was produced Carno distilled these profound ideas
• 34:30 - 35:00 into an accessible book for General readers which meant it was largely ignored by scientists instead of being heralded as a classic well this is the book it's carno's only publication Reflections on the Motive Power of fire 1824 a small book 118 Pages only published just 600 copies and in his own lifetime it's virtually unknown 20 years after the publication
• 35:00 - 35:30 William Thompson the Scottish physicist is absolutely intent on finding a copy he's here in Paris and the accounts we have suggest that he spends a great deal of time visiting book shops visiting the bookinist on the banks of the sen looking always asking for the book and the book sellers tell him they've never even heard of it
• 35:30 - 36:00 William Thompson who would later become Lord Kelvin a giant in this new field of thermodynamics was impressed by carno's idea that the movement of heat produced useful work in the machine but when he returned home he heard about an alternative Theory from a Manchester Brewer called James Jewel juel had this notion that caral was wrong that heat wasn't producing work just by its movement heat was
• 36:00 - 36:30 actually turning into mechanical Mark which is a very strange idea when you think about it we're all now used to thinking about energy and how it can take all different forms but it was a revolutionary idea that heat and something like mechanical energy were at bottom the same kind of thing the experiment had convinced juel of this was set up in the cellar of his
• 36:30 - 37:00 Brewery it converted mechanical movement into heat almost like a steam engine in Reverse he used falling weights to drive paddles around the drum of water the friction from this process generated a minute amount of heat only Brewers had thermometers accurate enough to register this tiny temperature increase caused by a
• 37:00 - 37:30 measured amount of mechanical work Jewels work mattered because it was the first time that anyone had convincingly measured the exchange rate between movement and heat he proved the existence of something that converts between heat and and motion that something was going to be
• 37:30 - 38:00 called Energy and it's for that reason that the basic unit of energy in the new International System of Units is named after him the Jewel juel and carno's ideas were combined by Thompson to produce what would later be known as the laws of thermodynamics the first law from Jewel's work states that energy can be converted from one form to another but
• 38:00 - 38:30 can never be created or destroyed the second law from carno's theory states that heat Flows In One Direction only from hot to cold in the second half of the 19th century this new understanding paved the
• 38:30 - 39:00 way for steam power to artificially produce ice ice making machines like this one were based on principles discovered by Michael Faraday who showed when ammonia changes from a liquid to a gas it absorbs heat from its surroundings it's part of what is now known as a refrigeration cycle in the first stage of this cycle gigantic Pistons compress ammonia gas
• 39:00 - 39:30 into a hot liquid the hot liquefied ammonia is pumped into condenser coils where it's cool and fed into pipes beneath giant water tanks then the pressure is released and the liquid ammonia evaporates absor absorbing heat from the surrounding [Music]
• 39:30 - 40:00 water gradually the tanks of water become blocks of [Music] ice by the 1880s many towns Across America had ice plants like this one which could produce 150 tons of ice a day for the first time artificially produced ice was threatening the Natural Ice trade created Creed by Frederick Tudor America's appetite for ice was
• 40:00 - 40:30 insatiable slaughter houses breweries and food warehouses all needed ice animals were disassembled on production lines in Chicago and the meat was loaded into ice cooled box cars to be shipped by railroad r on it way to the great meat packing centers of the nation through markets everywhere food of every sort safely and quickly delivered in refrigerator
• 40:30 - 41:00 time as fruit and vegetables became available out of season Urban diets improved making City dwellers the best fed people in the world and to keep everything fresh at home the Iceman made his weekly delivery to recharge the refrigerator ref Refrigeration makes a tremendous difference in people's lives first of all in the diet what it's
• 41:00 - 41:30 possible for them to eat uh they can go to the store once a week they don't have to go every day they can obtain at that store foods that are from almost anywhere in the world that have been transported and kept cool and then they can keep them in their own home eventually the Iceman disappeared as more and more households bought electric refrigerators these use the same basic principles as the old ice maker machines liquid ammonia circulating in pipes evaporates draining the heat away
• 41:30 - 42:00 from the food inside compressed by an electric pump the gas is condensed back into liquid ammonia and the cycle begins again the electric power companies love refrigerators because they ran all day and all night they may not have used that much power for each hour but they continued to use that so one of the ways that they sold r electrification was the possibility of having your own
• 42:00 - 42:30 refrigerator in the early days the freezer was used to freeze water nothing else freezing was seen as having the same damaging effects as Frost the man who would change this idea forever was a scientist and Explorer named Clarence bird's eye in 1912 Bird's ey set off on an expedition to Labrador and the
• 42:30 - 43:00 temperature dropped to 40° below freezing the Inuit had taught birdy how to ice fish by cutting a hole in the ice several feet thick when he caught a fish he found it froze almost as soon as it hit the air this process seemed to preserve the fish in a unique
• 43:00 - 43:30 way when you went to cook this fish it tasted just as good it fresh and he couldn't figure that out because when he froze fish at home they would taste terrible so when he got back home he finally tried to figure out what was the difference between this quick freezing and the usual freezing under closer examination he could see what was happening to the fish
• 43:30 - 44:00 cells with slow freezing large ice crystals formed which distorted and ruptured the cells when thawed the tissue collapsed and all the nutrients and flavor washed away the so-called mushy strawberry syndrome but with fast freezing only tiny ice crystals were formed inside the cells and these caused little damage it was all down to the speed of the freezing
• 44:00 - 44:30 process a simple concept but it took Clarence bird's eye another 10 years to perfect a commercial fast freezing technique that would mimic the natural process he'd experienced in Labrador in 1924 he opened a flash freezing plant in Gloucester Massachusetts that froze freshly landed fish atus 45° he then extended that to all sorts of other kinds of meats and products and
• 44:30 - 45:00 vegetables and almost single-handedly invented the frozen food industry refrigerators and freezers would eventually become icons of modern living but there was a less visible cold transformation happening at the same time this would also have a huge impact on Urban Life the cooling of the air itself three centuries had passed past since Cornelius dreel had shaken King James in Westminster now at the dawn of the 20th
• 45:00 - 45:30 Century Air cooling was about to shake the world tell me what is the lowdown on this air conditioning thing now you've started something by asking me [Music] that air conditioning was about to transform Modern Life and the person largely responsible was Willis carrier who started off working for a company that made [Music]
• 45:30 - 46:00 fans carrier is sent to Brooklyn for a very special job in 1902 the company that publishes the magazine judge one of the most popular full color uh magazines in America at this particular time is having a huge problem it's July in Brooklyn and the ink for which they which they use on their beautiful covers is sliding off the pages it will not stick because the
• 46:00 - 46:30 humidity is too high carrier using some principles that he's been developing as a young new employee of this Fan Company finds a way to get out the July 1902 run of the judge magazine and from there he begins to eventually build his air conditioning Empire it's based on a simple principle control of humidity through control of temperature that was Willis
• 46:30 - 47:00 carrier's idea he used Refrigeration to cool the water vapor in the humid air The Vapor condensed into droplets leaving the air dry and cool the demand for air conditioning gradually grew in the 1920s movie houses were among the first to promote the benefits people would flock there in summer to escape the
• 47:00 - 47:30 heat the movies are wildly popular and the air conditioning certainly helps to attract an audience especially if they happen to be walking down the street in a horribly hot day and they duck into this movie theater and have this wonderful [Music] experience air conditioning became increasingly common in the workplace too particularly in the South where textile and tobacco factories were almost unbearable without cooling when employees breathe good air
• 47:30 - 48:00 and feel comfortable they work faster and do a better job I think some people think these were nice um you know um compassionate employers who were cooling down the workplace for the workers but of course nothing could be further from the truth that that was that was an inadvertent byproduct but actually this was an a a a quality control device to control the breaking of fibers in in in Cotton Mills to to get consistent you know quality control in these various uh um Industries to control the the dust
• 48:00 - 48:30 that have beveled tobacco stemming room workers for um for decades I think the workers obviously went home and and to their unair conditioned Shacks in most cases and and uh and talked about how nice and cool it was working during during the day it's silly to suffer from the heat when you can afford the modest cost of air conditioning by the 1950s people were air conditioning their homes with Standalone
• 48:30 - 49:00 window units that could be easily installed this wasn't just an appliance it offered a new cool way of [Music] life walking down a a typical Southern Street prior to the air conditioning revolu Evolution you would have seen families individuals outside they would
• 49:00 - 49:30 have been on their porches on each other's porches uh there was a visiting tradition a real sense of [Music] community well I think all that changes with air conditioning and you you can walk down that same street and basically what you'll hear are not the voices of people talking on the porch you'll hear the wor of the [Music] compressors guess what we we' got an RCA room air conditioner I'm a
• 49:30 - 50:00 woman and I know how much pure air means to mother in keeping our rooms Clean and Free from death and [Music] d control of the cold has transformed City Life Refrigeration helped cities expand outwards by enabling large numbers of people to live at Great distances from their source of
• 50:00 - 50:30 food air conditioning enabled cities to expand upwards Beyond 20 stories high winds make open Windows impractical but with air conditioning 100 story skyscrapers were [Music] possible Technologies emerge which not only worked to insulate Human Society
• 50:30 - 51:00 against the evils of cold but turned cold into a productive manageable effective resource on the one hand the steam engine on the other the refrigerator those two great symbols of 19th century World which completely changed the society and economy of the planet all that is part of I think what we could call bringing cold to Market
• 51:00 - 51:30 turning it from an evil agent that you feared into a force of nature from which you could profit the explosive growth of the modern world over the last two centuries owes much to the conquest of cold but this was only the beginning of the Journey Down the temperature scale going lower would be even harder but would produce greater Wonders that promise extraordinary Innovations for the
• 51:30 - 52:00 future with rival scientists racing toward the final frontier the pace quickens and the molecular dance slows as they approach the Holy Grail of cold absolute [Music] zero [Music]
• 52:00 - 52:30 [Applause]
• 52:30 - 53:00 [Music] [Music] a century ago Antarctic explorers were pushing further and further towards the coldest place on Earth the South Pole
• 53:00 - 53:30 where temperatures can plummet to minus 80° the competition to reach this goal was matched by a less publicized but equally daunting scientific Endeavor the attempt to reach the coldest point in the universe absolute zero was it possible to attain this ultimate limit of temperature- 273°
• 53:30 - 54:00 C only in a laboratory by liquefying gases could scientific adventurers take the first steps towards this Holy Grail a place where atoms come to a virtual standstill utterly drained of all thermal energy Among The Front Runners in the race towards absolute zero was James derer a professor at the Royal Institution in London it will be the greatest achievement of our age a in
• 54:00 - 54:30 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 The Descent to a temperature within 5° of zero would open up new vistas of scientific inquiry which would add immensely to our knowledge of the properties of matter James duer is a canny um and I think
• 54:30 - 55:00 very ambitious practically minded Scottish scientist he could really show both his colleagues and the fee paying audiences um 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 immersion in liquid oxygen derer invented a thermal
• 55:00 - 55:30 insulated container to carry out his research and scientists to this day still call it a duer flask now let's see what [Music] happens this science to be accepted by the public uh though it is a little mystifying it did
• 55:30 - 56:00 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 deer's dream was to take on on the mantle of the royal institution's greatest scientist Michael
• 56:00 - 56:30 Faraday 70 years earlier Faraday had done experiments showing that Under Pressure gases like chlorine and ammonia liquefy he was curious to see if this method of pressurizing gases into liquids could be used for all gases but some what he called the permanent gases oxygen nitrogen hydrogen would not liquefy no matter how much
• 56:30 - 57:00 pressure he applied so he abandoned this line of research Faraday was a mindful of subtle powers of divination into nature 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
• 57:00 - 57:30 130° C it was not until 1873 that a Dutch theoretical physicist Vander vals 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 [Music]
• 57:30 - 58:00 temperature at last he had shown the way to liquefy the so-called permanent gases was to cool them oxygen was first and then nitrogen reaching a new low temperature of almost -200 de Centigrade only the last of the permanent gases remains to be liquefied hydrogen in the vicinity of
• 58:00 - 58:30 minus 250° Centigrade it will be the greatest achievement of our age a Triumph of science duer was determined to be the first to ascend what he called Mount hydrogen but he was not [Music] alone the competitor deer feared most was a
• 58:30 - 59:00 brilliant Dutchman hia cing ones cameling ones was uh younger than duer um and to a certain extent looked up to the Scotsman as his senior um duer didn't have the same if you'll pardon the expression warm feelings towards his rival in the race for cold deer recognized that caming Onis had a new radical approach to science
• 59:00 - 59:30 and was planning an industrial scale lab when Hest took over the Physics laboratory in Len 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 lighten University and it was all there he was explaining what to do in the next years and he was talking about liquefying gazes making Dutch physics famous abroad and well it was amazing how farsighted all those Visions
• 59:30 - 60:00 were cerling ones' 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 deer and honest could not have been more different derer was very secretive about his work hiding crucial parts of
• 60:00 - 60:30 apparatus from public view before his lectures Hest on the other hand openly shared his lab's steady progress in a monthly Journal Hest was the tortoise to deer's hair in the case of duer you had a brilliant experimentor a person who could actually build the instruments himself and a person who really believed in The Brute Force approach and that is have
• 60:30 - 61:00 your instruments set up your experiment and try as hard as you can and then you'll get the results you want to get uh in the case of kones you have a totally different approach he is the beginning of what later on was known as big science unlike like derer Hest thought detailed calculations based on Theory were vital before embarking on
• 61:00 - 61:30 experiments he was a disciple and close friend of Vander bals whose theory had helped solve the problem of liquefying permanent gases though their approaches were different caming Onis and derer 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
• 61:30 - 62:00 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 at an even lower
• 62:00 - 62:30 temperature the second liquid goes on to cool the next gas and so on step by step the liquefied gases become colder and colder each one is used to lower the temperature of the next gas sufficiently for it to liquefy in the final stage where hydrogen gas is cooled the idea was to put it under enormous pressure 180 times atmospheric pressure and then suddenly
• 62:30 - 63:00 release it through a valve this would trigger a massive drop in temperature sufficient to turn hydrogen gas into liquid hydrogen atus 22° just 21° above absolute zero here was the risky bit because his apparatus was um 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
• 63:00 - 63:30 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 deer had many explosions in his lab several times assistants lost an eye as
• 63:30 - 64:00 shards of glass catapulted through the air in the notebook he actually writes chuts down many details of what happened in the apparatus but not what happened to his assistants so somehow you get the impression that apparatus is more important than the assistants over in lighten onest was facing anxious City officials who were so worried about the risk of explosions that they ordered the lab to be shut
• 64:00 - 64:30 down guer wrote a letter of protest on behalf of Honis but the lien lab remained closed for 2 years well hus had to wait and to wait and to wait duer was already starting uh with liquifying hydrogen and on had the apparatus to do so too but it just couldn't start so we had lost the battle
• 64:30 - 65:00 before it was even [Music] begun the year is 1898 Tu 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 hydrogen by using liquid oxygen they brought down the temperature of the hydrogen gas to -20° C they increased the pressure till the
• 65:00 - 65:30 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 cm deer had l liquified hydrogen the last of the so-called permanent gases to prove it he took a small tube
• 65:30 - 66:00 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 der thought that he had done the most amazing feat of Science in the world that he would be immediately celebrated for them and get whatever prizes there were available and that
• 66:00 - 66:30 didn't happen I think for duer it was the ambition of a mountaineer you've climbed the highest mountain peak that you 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 new Mountain was helium a recently discovered inert gas that was originally thought only to exist on the
• 66:30 - 67:00 sun vander's Theory predicted helium would liquefy at an even lower temperature than hydrogen at around 5° above absolute zero now all derer had to do was obtain some it should not have been difficult the two chemists who had discovered the inert gases Lord rley and William Ramsey often worked together in the lab next door unfortunately derer had made enemies of both of them by refusing to
• 67:00 - 67:30 collaborate and belittling their achievements so they had no desire to share their helium cameling only was faced with the same problem as derer which is where can I get a supply of helium gas and he actually asked derer to try and collaborate with him too and de said I'm having such a problem getting the gas by myself I can't possibly give you anything I'd like to but I can't eventually each found a supply but honest's industrial approach paid
• 67:30 - 68:00 dividends after 3 years he had amassed enough helium gas to begin experiments the tortoise was beginning to pull away from the hair at the same time derer was running out of resources to make matters worse a lab assistant turned a knob the wrong way releasing a whole canister of helium into the air for 6 months the lab couldn't do any
• 68:00 - 68:30 work at one point duer R to comeon is telling telling him that he's not in the race anymore he thinks that the problems for liquefying helium are such that he's not able to complete the job the battlefields of science are the centers of a Perpetual Warfare in which there is no hope of a
• 68:30 - 69:00 final Victory to serve in the scientific Army to have shown the initiative is enough to satisfy the legitimate ambition of every Earnest student of nature thank you [Music]
• 69:00 - 69:30 in the summer of 1908 onest summoned his chief assistant fim from across the river they were finally ready to liquefy helium at 5:45 on the morning of July the 10th he assembled his team at the lab they had rehearsed the drill many times before Leiden was a small University town and the word quickly
• 69:30 - 70:00 spread that this was the big day it took until lunchtime to make sure the apparatus was purged of 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 at 6:30 in the evening the temperature began to drop below that of liquid hydrogen but then it seemed to
• 70:00 - 70:30 stick Hest doesn't know why this is and a colleague comes in and he suggest that that means maybe they've actually succeeded and they don't even know it yet so Hest 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° c just 5° above absolute zero and
• 70:30 - 71:00 finally produced liquid helium this Monumental achievement eventually won on us the Nobel Prize when James derer heard that he had lost the race to caming onest it reignited a festering resentment Durer berated his longsuffering assistant Lennox for failing to provide enough helium only this time Lennox had had enough he walked out of the Royal Institution
• 71:00 - 71:30 vowing never to return until derer was dead and he kept his word for duer it was the end of his low temperature research James deer's dream of reaching absolute zero was over although he had won the first race to liquefy hydrogen it never attracted the same accolades as liquefying helium he
• 71:30 - 72:00 abandoned low temperature physics and moved on to investigate other phenomena such as the science of soap [Music] bubbles 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 goalposts move as you're playing the
• 72:00 - 72:30 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
• 72:30 - 73:00 out on the race this is just what happened in lien as hs's team began to investigate how materials conduct electricity at very low [Music] temperatures they observed in a sample of mercury that at around 4° above absolute zero all resistance to the flow of electricity abruptly
• 73:00 - 73:30 vanished Hest later invented a word to describe this new phenomenon he called it superconductivity we have a circular ring of permanent magnets which are producing a magnetic field and now when we we put a super conducting Puck over it and give it a little push the magnetic field repels the
• 73:30 - 74:00 superconductor the magnetic field from the track induces a current in the superconducting puck which in turn creates an opposite magnetic field that makes the puck levitate and it produces a magnetic field like a North Pole against the North Pole and that's why you have the repulsion as the puck warm Ms up its superconducting properties vanish along with its magnetically induced field for
• 74:00 - 74:30 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 superconductivity 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
• 74:30 - 75:00 liquid helium cools until at 2° 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
• 75:00 - 75:30 into a super fluid which displays some really odd properties here I have a beaker with an unglazed ceramic bottom of ultra fine paracity ordinarily this container with tiny pores can hold liquid helium but the moment the helium Turns Super fluid it leaks through we call this kind of flow a super flow super fluid helium can do things we
• 75:30 - 76:00 might have believed impossible it appears to defy gravity a thin film can climb walls and Escape its container this is because a super fluid has zero viscosity it can even produce a frictionless fountain one that never stops flowing super fluidity and superconductivity were baffling concepts for scientists new radical theories were needed to explain
• 76:00 - 76:30 them in the 1920s quantum theory was emerging as the best hope of understanding these strange phenomena its central idea was that atoms do not always behave like individual particles sometimes they merge together and behave like waves they can also be particles and waves at the same time even for great minds like
• 76:30 - 77:00 Albert Einstein this strange Paradox was hard to accept in 1925 a young Indian physicist satendra 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
• 77:00 - 77:30 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
• 77:30 - 78:00 could only dream about making such a condensate which has never been seen in nature 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
• 78:00 - 78:30 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 wavelike properties so instead of points like that you have little wave packets like that move mov 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
• 78:30 - 79:00 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 behaves 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 whether it's this one or that one or that one or that one or that one or
• 79:00 - 79:30 there and it's there and 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 gayy freely bouncing into things sometimes going fast sometimes going slow but on the Bose condensate I'm everywhere at once I've
• 79:30 - 80:00 lost my identity I don't know who I am anymore I'm at rest and all the other atoms around 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 [Music]
• 80:00 - 80:30 Dan klepner and his MIT colleague Tom GAC began to try to make a Bose Einstein condensate in [Music] hydrogen as we started out the search for both 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 uh atoms will
• 80:30 - 81:00 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 the Bose Einstein condensation Ker's 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 coal trap unfortunately sometimes one atom flipped another which triggered a
• 81:00 - 81:30 release of energy that raised the [Music] temperature it was a frustrating time for us because our methods were so complicated we were having a hard time moving forward now others decided to take up the challenge two physicists from from MIT met in Boulder Colorado and came up with a different approach to the problem rather than focusing on the
• 81:30 - 82:00 lighter atoms of the periodic table they 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 and lithium would be easier and there are some good reasons for thinking that but we had we had other ideas yeah sort of gut intuition in some sense their plan was to use a laser beam
• 82:00 - 82:30 to cool the atoms a technique that had already been tried by physicists 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 lasers can cool them [Music] down when the stream of light particles from the laser hits the selected atoms in the gas cloud they slow down and become
• 82:30 - 83:00 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 news scientist had arrived at
• 83:00 - 83:30 MIT it was in late 91 or early '92 that we had an idea an idea how a different arrangement of laser beams would be able to cool atoms to higher density and it worked and this was really a trigger point I will never forget get the excitement in those groups group meetings when we discussed what do be next because with higher density there many things you can do could we now push
• 83:30 - 84:00 to bza Einstein condensation you see well lots of cables and electron all the resources of cly's lab were redirected to make a condensate in sodium atoms and right here this is an atomic beam oven what is wrapped in tint 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 vapor the sodium atoms which we
• 84:00 - 84:30 tried to B Einstein [Music] condense 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 a science moves on and uh um we're all mortal and um you want
• 84:30 - 85:00 to do things while MIT was installing its sophisticated lasers Carl Wyman's approach was small is beautiful in some cases he was ripping open old fax machines and taking out the little chip inside that made the laser and showed that you could take these lasers and put them into a homebuilt piece of oper uh apparatus stabilize the laser and use them to do spectroscopy and Laser cooling this is actually our first
• 85:00 - 85:30 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 the all the different directions and have just a little bit of the atoms we wanted to cool as well as bombarding the atoms with laser they also trapped them in a strong magnetic field we would try this sort of magnetic
• 85:30 - 86:00 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 but MIT had its own plans there was a sense of competition
• 86:00 - 86:30 but it was what I would call Friendly competition 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 both using using magnetic trapping and lasers to cool their atoms but for the final push towards absolute zero to turn these atoms of gas into the quantum State
• 86:30 - 87:00 Einstein had predicted they needed one more cooling technique evaporative cooling it's just like with this coffee the steam coming off 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 in a sort of magnetic Bowl and uh 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
• 87:00 - 87:30 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 atoms that can escape until finally the remaining atoms cluster near the bottom of the bowl huddled together they get colder and colder and denser and denser and eventually in this way evaporation forces the Bose Einstein condensation to
• 87:30 - 88:00 occur the race to produce of Bose Einstein condensate was intensifying at every Major meeting uh Eric Cornell and I gave talks or talk to each other we were keenly aware uh that we were both working towards to see him going in June 1995 the boulder group was working Round the Clock knowing that MIT and several other labs were also poised
• 88:00 - 88:30 to produce the first condensate an official visit from a government funding agency was the last thing they needed yeah we didn't want to close down the lab or clean up our lab or put up 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 uh everyone continued to work and I made them keep their voices down and uh talked to them rather in A hurried way and then sort of shuffled them out the
• 88:30 - 89:00 door and they all had a slightly puzzled look on their face cuz 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 uh 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 1994 5 turned out to be a big day in the history of physics the boulder group seemed to have made what Einstein had theorized 70 years
• 89:00 - 89:30 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 uh Bose Einstein condensation [Music]
• 89:30 - 90:00 the conate is sort of like a vampire if the sunlight even once falls on it it's dead and so uh it it's its realm is the realm of the dark but we can take pictures of them because we strobe the laser light really fast and uh even as the condensates dying it cast a shadow and the shadow is Frozen in in in the film at a temperature of 170 billionth of a degree above absolute zero Wyman and Cornell created a pure Bose Einstein condensate in a gas cloud of just 3,000
• 90:00 - 90:30 atoms of Rubidium the first in the universe as far as we know 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 uh is far above absolute zero on this scale imagine that room temperature was represented by London thousands of kilometers from here then on that scale if we imagine right here where I'm standing and Boulder is absolute zero
• 90:30 - 91:00 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 lead away from absolute [Music] zero within months of the boulder group's success wulfgang kly produced an even larger condensate from half a million sodium atoms slowed down to a
• 91:00 - 91:30 virtual standstill causing their wave functions to overlap to produce an entirely new state of [Music] matter at last quantum mechanics was more than just a theoretical construct it was something that could be seen with the naked eye Cornell cly and Wyman shared the Nobel Prize for physics in 2001 one of the
• 91:30 - 92:00 things Nobel Prize means and the ceremony means that it everybody remembers Eric's the person who forgot to bow to the king there was a breakdown of protocol on my part there was no excuse because they actually drill it to it's more like a you have a series of rehearsals practicing how to bow to the king and I somehow managed to bollock it up at the last possible
• 92:00 - 92:30 moment and I thought maybe you know Carl who came after me would do this make the same mistake and then no one would figure it out but uh no he was [Music] perfect I heard about the Nobel Prize when I was woken up by a telephone call which was at I think 5:30 in the morning so you wake up you go to the telephone and somebody tells you congratulation you've won the Nobel Prize you're still tired your brain is not fully functional
• 92:30 - 93:00 but you realize this is big and and what you feel is an 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 greater Adventure the pursuit of science offers no guarantee of success but for The Godfather of ultra cold atoms persistence eventually paid
• 93:00 - 93:30 off in 1998 after 20 years of struggling to obtain a condensate in hydrogen Dan Kelner finally succeeded for a few fleeting moments his dream came true course we were delighted and I think everyone was delighted because we've been working on it for so long it's kind of embarrassing to have this group which helped start the work and was working away there fruitlessly while everyone was enjoying success when we
• 93:30 - 94:00 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 had this Standing Ovation which Dan clner received at the vena summer school when he announced Bosa Einstein condensation in h everybody just got up and gave it was
• 94:00 - 94:30 sort of like an opera where everybody just cheered and people were crying and uh 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 uh very moving very moving moment for the Pioneers who had realized Einstein's dream and created condensates it was the end of an extraordinary
• 94:30 - 95:00 decade of physics now there was a new challenge to work out what to do with [Music] 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 uh in
• 95:00 - 95:30 vacuum and if somehow we could use this system to get light down to you know to a human level I thought that was just absolutely [Music] fascinating 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 186,000 m/s but when the pulse hits the
• 95:30 - 96:00 condensate it slows down to the speed of a bicycle so light pulse might start out being 1 to two miles long in free space it goes into our medium and uh since the front edge enters first that will slow down the B Edge is still in free space that'll catch up and that'll create that uh uh compression and it'll end up being compressed from 1 to two miles down to 01 Micron or even smaller than
• 96:00 - 96:30 that you could say well gee it's easy 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 turn into heat you can never get that information back in our case uh when we stop it the information is not lost because that's stored in the medium and then when we are time to revive it the system has all the information to revive the light PS and it can move on one day Ultra cold atoms will
• 96:30 - 97:00 probably be used to store and even process information even now cold atoms are being turned into prototype quantum computers as a Quantum mechanic I Engineer atoms to make a computer out of atoms you have to somehow get atams to register information and then to process it why why build quantum computers
• 97:00 - 97:30 because they're cool it's fun and we can do it right I mean we actually can take atams and if we ask them nicely they'll compute that's a lot of fun I mean have you ever talked to an adom recently and had it talk back it's great uh yes look at that unlike ordinary computers where each decision is based around a bit of information and is either a zero or a one in the quantum world the rules change at first glance a quantum
• 97:30 - 98:00 computer looks almost exactly the same but quantum mechanics is weird it's funky okay it's weird when you do Quantum Computing you want to make this weirdness work for you so now let's look at our Quantum bit or Cubit a cubit can not only be a zero or one it can also both be a zero and one at the same time it's almost like a form of parallel compation but in a parall computer One processor does this one processor does that so you have two
• 98:00 - 98:30 processors doing this and that process and that at the same [Laughter] time today computers are limited in the amount of information they can handle by the Heat and number of the circuits here within a giant dwer flask lies a prototype quantum computer surrounded by
• 98:30 - 99:00 its super cooled super conducting magnet in the future Quantum Computing could be used to predict incredibly complex Quantum interactions such as how a new drug acts on faulty [Music] biochemistry or to solve complex encryption problems like coding prime numbers that are the key to Internet Security already supercooled Quantum
• 99:00 - 99:30 devices are mapping the magnetic activity of the [Music] brain often the promised benefits from a scientific breakthrough take a long time to emerge many predicted that by this Century energy saving superconducting power lines and maglev bullet trains would be crisscrossing the continents perhaps as world energy supplies decline these Technologies once seen as too costly will start to take
• 99:30 - 100:00 off this weird Quantum world is part of a new frontier opened up by The Descent towards absolute [Music] zero it's been been a remarkable Journey for scientists into unknown territories far beyond the narrow confines of Earth on the Kelvin temperature scale
• 100:00 - 100:30 which begins at Absolute Zero the temperature of the Sun is around 5,000 Kelvin at 1,000 Kelvin Metals melt at 300 we reach what we think of as room temperature air air liquefies at 100 Kelvin hydrogen at 20 helium at 4 Kelvin the deepest outer space is 3°
• 100:30 - 101:00 above absolute zero but The Descent doesn't stop there with ultra cold refrigerators the decimal point shifts three places to a few 1,000 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
• 101:00 - 101:30 shift four more decimal places until we reach the coldest recorded temperature in the universe created at a lab in Helsinki 100 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 0 Kelvin getting to absolute zero is
• 101:30 - 102:00 tough nobody's actually been there at Absolute 0.00000000 with an infinite number of zeros that last little tiny bit of heat becomes harder and harder to get out and in particular the time scales 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 uh extracting an amount of energy that's sufficiently small it would indeed take the age of the universe to do it also you actually
• 102:00 - 102:30 need an apparatus the size of the universe to do it but that's another story absolute zero may be unreachable but by exploring further and further towards this ultimate destination of cold the most 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 [Music]
• 102:30 - 103:00 cold [Music]
• 103:00 - 103:30 [Applause] [Music] Nova is a production of WGBH Boston