A HISTÓRIA DA ENERGIA - Documentário (2012)

how did humans acquire the power to transform the planet like this looking at the Earth at night reveals to us just how successful we've been in harnessing and manipulating energy and how important it is to our existence [Music] energy is vital to us all we use it to build the structures that surround and protect us we use it to power our transport and light our homes and even more crucially energy is essential for life itself without the energy we get from the food we eat we die but what exactly is energy and what makes it

so useful to us in attempting to answer these questions scientists would come up with a strange set of laws that would link together everything from engines to humans to Stars it turns out that energy so crucial to our daily lives also helps us make sense of the entire [Music] universe this film is the Intriguing story of how we discovered the rules that drive the universe it's the story of how we realized that all forms of energy are destined to degrade and fall [Music] apart to move from order to disorder it's the story of how this

amazing process has been harnessed by the universe to create everything that we see around us [Music] [Applause] over the course of human history we've come up with all sorts of different ways of extracting energy from our environment everything from picking fruit to burning wood to sailing boats to water wheels but around 300 years ago something incredible happened humans developed machines that were capable of processing extraordinary amounts of energy to carry out previously unimaginable tasks now this happened thanks to many people and for many different reasons but I'd like to begin this story with one of

the most intriguing characters in The History of Science one of the first to attempt to understand energy [Music] gotfried Li nitz was a diplomat scientist philosopher and genius he was forever trying to understand the mechanisms that made the universe work livets like s several of his great contemporaries was absolutely convinced that the world we see around us is a vast machine designed by a powerful and wise person and if you could understand how machines worked you could therefore understand how the universe and the principles that had been used to make the universe worked as well

and so there was an extremely close relationship for lib nits between um Theology and philosophy on the one hand and engineering and mechanics on the other it was this relationship between philosophy and Engineering that in 1676 would lead him to investigate what at First Sight seemed to be a very simple [Music] question what happens when objects collapse this is what Li nits and many of his contemporaries were grappling with so when these two balls bump into each other the movement of one gets transferred to the other it's as though something's being passed between them and

this is what liet called The Living Force he thought of it as as stuff as a real physical substance that gets exchanged during collisions lits argued that the world is a living machine and that inside the machine there is a quantity of living Force put thereby God at the creation that will stay the same forever so the amount of living force in the world will be conserved the puzzle was to define it Li nits would soon find a simple mathematical way to describe the living Force but he would also see something else he realized that

in gunpowder fire and steam his living force was being released in violent and Powerful ways [Music] if this could be harnessed it could give humankind unimaginable power liet would soon become fascinated with ways of capturing the living Force a prolific letter writer liet struck up correspondence with a young French scientist called Deni [Music] Papa as they corresponded liet and papa realized the living Force released in certain situations could indeed be harnessed heat could be converted into some form of useful [Music] action but how far could this idea be taken Papa was in no doubt this

is an extract from his letter to liet I can assure you that the more I go forward the more I find reason to think highly of this invention which in Theory May augment the powers of man to Infinity but in practice I believe I can say without exaggeration that one man by this means will be able to do as much as a hundred others can do without it now you might expect me at this point to tell you that livess and papan changed the world forever well they hadn't their ideas had been profound and far-reaching

yes but they hadn't really moved things forward for that you need something much more tangible you need Innovation industry you need countless skilled workers and craftsmen who are going to apply these ideas to experiment with them in in novel and new ways well in the century that followed livits and papan this would take place in the most dramatic way [Music] imaginable 150 years after livets and papan discussions the living Force had been harnessed in spectacular ways the machines they dreamed of had become a reality steam engines were Now The Cutting Edge of 19th century technology

if you look at steps in Civilization then one great step was the steam engine because it replaced muscle animal muscle including our muscle by steam power and the steam power was effectively Limitless and hugely important to doing almost unimaginable [Music] things but steam technology would do more than just transform Human Society it would uncover the truth about what life had called The Living force and reveal new insights about the workings of our [Music] universe this is cross Ness in southeast London it's an incredible industrial Cathedral and home to some of the most impressive Victorian steam

engines ever built [Music] constructed in 1854 cross Nest houses four huge engines that once required 5,000 tons of coal each year to drive their 47 ton beams [Music] everything about this place seems to have been built to impress from the lavish Iron Work the grand pillars like something out of a a Greek or Roman Temple it's a sort of effort You' think would have been uh lavished on a luxury ocean liner for the Rich and Famous and yet this place was built to process sewage although only a few workers and Engineers would have seen the

insides of this place steam had become such a vital part of British power and economic Prosperity that it was afforded almost religious respect but for all the great success and immense power that engines were bestowing on their creators there was still a great deal of confusion and mystery surrounding exactly how and why they worked in particular questions like how efficient could they be made were there limits to their power ultimately people wanted to know just what might it be possible to achieve with steam [Music] the reason these questions persisted was simple almost no one had

understood the fundamental nature of the steam engine very few were aware of the cosmic principle which underpinned it these great lumbering machines that we think of as the early steam engines actually were the seed of understanding of everything that goes on in the universe as unlikely as it sounds steam engines held within them the secrets of the cosmos [Music] this is the chatau dean in Paris events here would motivate one man's journey to uncover the cosmic truth about the steam engine and help to create a new science the science of heat and motion thermodynamics [Music]

in March 1814 during the Napoleonic Wars when Napoleon and his armies were fighting elsewhere Paris itself came under sustained attack from the combined forces of Russia Prussia and Austria and citizens of the city were deployed around key locations to protect them now this Shadow was being defended by a group of inexperienced young students students who were forced to retreat under sustained artillery fire one of them was a brilliant young scientist and Soldier his name was Nicola Leona Sadi Caro and the humiliation he felt personally would drive him and motivate him to uncover a profound insight

into how all engines work Caro came from a highly respected mil military family after the French defeat here and elsewhere around Europe he became determined to reclaim French [Music] Pride what really bothered Caro was the technological superiority that France's enemies seemed to possess and Britain in particular had this huge Advantage both militarily and economically because of its mastery of steam power so Carno vowed to really try and understand how steam engines work and use that knowledge for the benefit of France he says absolutely explicitly that if you could take away steam engines from Britain then

the British Empire would collapse and he's writing in the wake of French military defeat and he proposes to analyze literally the source of British power by analyzing the way in which fire and heat engines work living on half pay with his brother eoit in a small apartment in Paris in 1824 Carno wrote the now legendary Reflections on the Motive Power of fire in just under 60 Pages he developed and abstracted the fundamental way in which all heat engines work Carno saw that all heat engines comprised of a hot Source in cooler surroundings now Caro believed

that heat was some kind of substance that would flow like water from the hot to the cool and just like water falling from a height the flow of heat could be tapped to do useful work [Music] carno's crucial Insight was to show that to make any heat engine more efficient all you had to do was to increase the difference in temperature between the Heat source and the cooler surroundings this idea has guided Engineers for 200 years ultimately a car engine is more efficient than a steam engine because it runs at a much hotter temperature jet

engines are more efficient still thanks to the incredible temperatures they can run [Music] at Carno had revealed that heat engines weren't just a clever invention they were tapping into a deeper property of nature they were exploiting the flow of energy between hot and cold Carno had glimpsed the true nature of heat engin and in the process began a new branch of science but he would never see the impact his idea would have on the World In 1832 a Cera epidemic spread through Paris it was so severe it would kill almost 19,000 people now back then

there was no real scientific understanding of how the disease spread so it must have been terrifying Carno undaunted by the risks decided to study and document the spread of the disease but unfortunately he contracted it himself and was dead a day later he was just 36 years old a lot of his precious scientific papers were burnt to stop the spread of contagion and his ideas fell into temporary obscurity it seems the world wasn't quite ready for [Applause] Carno Carno had made the first great contribution to the science of thermodynamics but as the 19th century progressed

the study of heat motion and energy began to grip The Wider scientific Community soon it was realized that these ideas could do much more than simply explain how heat engines worked just as live had suspected with his notion of living Force these ideas were applicable on a much grander [Music] [Music] scale by the mid 19th century scientists and Engineers had worked out very precisely how different forms of energy relate to each other they measured how much of a particular kind of energy is needed to make a certain amount of a different kind let me give

you an example the amount of energy needed to heat 30 mL of water by 1° centigrade is the same as the amount of energy needed to lift this 12 1/2 kg weight by 1 M the deeper Point here that people realized was that although mechanical work and heat may seem very different they are in fact both facets of the same thing energy this idea would come to be known as the first law of thermodynamics the first law reveals that energy is never created or destroyed it just changes from one form to another 19th century scientists

realized this meant the total energy of the entire universe is actually fixed amazingly there's a set amount of energy that just changes into many different forms so in a steam engine energy isn't created it's just changed from heat into mechanical work [Music] but impressive though the first law is it begged an enormous question what exactly is going on when one form of energy changes into another in fact why does it do it at all the answer would in part be found by German scientist Rudolph clausius and it would form the basis of what would become

known as the second law of Thermodynamics Rudolph clausius was a brilliant German physics student from Pomerania who studied in Berlin and at a ridiculously young age became a very brilliant professor in Berlin and then in Zurich at the new technology University unity set up there in Switzerland and in the 1850s and 60s clausius offered what is really the first coherent full-blown mathematical analysis of how thermodynamics Works clausius realized that Not only was there a fixed amount of energy in the universe but that the energy seemed to be following a very strict rule but simply energy

in the form of heat always moved in one particular direction this Insight of his is in fact one of the most important ideas in the whole of science as clausus put it heat cannot of itself pass from a colder to a hotter body this is a very intuitive idea if left alone this hot mug of tea will always cool down what this means is that heat will pass from the hot mug say to my hand and then again from my hand to my chest this might seem completely obvious but it was a crucial Insight the

flow of heat was a oneway process that seem to be built very fundamentally into the workings of the entire [Music] universe of course objects can get hotter but you always need to do something to them to make this [Music] [Applause] happen left alone energy seems to always go from being concentrated to being dispersed [Music] one of my favorite statements in science it was made by the biochemist Albert and George who said that science is all about seeing what everyone else has seen but thinking what no one else has thought and he Rudolph clausius um looked

at the everyday world and saw what everyone else had seen that heat does not flow spontaneously from a cold body to a hot body it always goes the other way but he didn't just say ah I see that he actually sat down and thought about it clausius brought together all these ideas about how energy is transferred and put them into mathematical context it could be summarized by this [Applause] [Music] equation now what clausius did was introduce a new quantity he called entropy this letter s basically what it's saying in the context of this equation is

that as heat is transferred from hotter to colder bodies entropy always [Music] increases entropy seem to be a measure of how heat dissipates or spreads out as hot things cool their entropy increases it appear to clausius that in any isolated system this process would be irreversible clausius was so confident about his mathematics that he figured out that this irreversible process was going on out there in the wider Cosmos he speculated that the entropy of the entire universe had to be increasing towards a maximum and that there was nothing we could do to avoid this this

idea became known as the second law of Thermodynamics and it turned out to be stranger and More Beautiful more Universal than anything clausius could have [Music] imagined the second law of Thermodynamics seemed to say that all things that gave off heat were in some way connected together all things that gave off heat were part of an irreversible process that was happening everywhere a process of spreading out and dispersing a process of increasing [Music] entropy it seemed that somehow the universe shared the same fate as a cup of tea the wonderful thing about the the Victorian

scientists is that they could make these great leaps and that they could see that their study of thermometer in a Bea actually could be trans could be extrapolated could be enlarged to Encompass the whole universe [Music] despite the successes of thermodynamics in the middle of the 19th century there was great debate and confusion about the subject what exactly was this strange thing called entropy and why was it always increasing answering this question would take an incredible intellectual leap but it would end up revealing the truth about energy and the many forms of order and disorder

we see in the universe around [Music] us many scientists would tackle the mysterious concept of entropy but one more than any other would shed light on the truth he'd show what entropy really was and why over time it always must increase his name was ludvik boltzman and he was one of science's true revolutionaries boltzman had been born in Vienna in 1844 it was a world of scientific and cultural certainty but boltzman took little notice of the entrenched beliefs of his contemporaries to him the physical world was something best explored with an open mind boltzman wasn't

your stereotypical scientist in fact he had the kind of temperament that most people might associate with great artists he was ruthlessly logical and analytical yes but while working he'd go through periods of intense emotion and these would be followed by terrible depressions which would leave him completely unable to think clearly he had terrible sort of mental crises and breakdowns in which he really thought that the world was coming apart at the seams and yet these were also accompanied by some of the most profound insights into the nature of our world outside of mathematics boltzman was

passionate about music and was captivated by the Grand and dramatic operas of Vagner and the raw emotion of beatoven he was a brilliant pianist and could lose himself for hours in the works of his favorite composers just as he could lose himself in deep mathematical theories [Music] [Applause] boltzman was a scientist Guided by his emotions and instincts and also by his belief in the ability of mathematics to unlock the secrets of nature it was these traits that would lead him to become one of the champions of a shocking and controversial new Theory one that would

describe reality at the very smallest scales fast morer than anything we could see with the naked eye during the second half of the 19th century a small group of scientists began speculating that at the smallest scales the universe might operate very differently to our everyday [Music] experiences if you could look close enough it seemed possible that the Universe might be made of tiny hard particles in constant motion [Music] viewed in terms of atoms heat would suddenly become a much less mysterious concept boltzman and others saw that if an object was hot it simply meant that

its atoms were moving about more rapidly viewing the world as atom seem to be an immensely powerful idea but this picture of the universe had one seemingly insurmountable problem how could trillions and trillions of atoms even in a tiny volume of gas ever be studied how could we come up with mathematical equations to describe all of this after all atoms are constantly bumping into each other changing direction changing speed and there are just so many of them it seemed almost an impossible problem but then boltzman saw there was a way boltzman saw more clearly than

anyone that for physics to explain this new strata of reality it had to abandon certainty [Music] instead of trying to understand and measure the exact movements of each individual atom boltzman saw you could build working theories simply by using the probability that atoms will be traveling at certain speeds and in certain directions [Music] boltzman had transported himself inside matter he'd imagined a world beneath our everyday reality and found a mathematics to describe it it would be here at this scale that boltzman would one day manage to unlock Energy's deepest secret despite the widespread hostility to

his theories [Music] boltzman's ideas were highly highly controversial and you have to remember that you know today we take Adams for granted but the reason we take Adams for granted is precisely because boltzman's mathematics married up so beautifully with experiments [Music] [Music] one of the most surprising aspects of this story is that many of boltzman's contemporaries viewed his ideas about atoms with intense hostility [Applause] today the existence of atoms the idea that all matter is composed of tiny particles is something we accept without question but back in boltzman's time there were notable eminent physicists who

just didn't buy it why would they no one had ever seen an atom and probably no one ever would how could these particles be considered as real [Music] after one of boltzman's lectures of atomic theory in Vienna the great Austrian physicist Ernst Mar stood up and said simply I don't believe that atoms exist it was both cutting and dismissive and for such a comment to come from a highly regarded scientist like Ern Mar it would have been doubly hurtful [Music] they argued that no atoms don't exist they're names labels convenient fictions calculating devices they don't

really exist we can't observe them no one's ever seen one and for that reason so Boltz spun's critics said he was a [Music] fantasist but that boltzman was right he peered deeper into reality than anyone else had dared and seen that the Universe could be built from the atomic hypothesis and understood through the mathematics of probability the foundations and certainty of 19th century science were beginning to [Music] crumble as boltzman stared into his Brave New World of atoms he began to realize his new vision of the universe contained within it an explanation to one of

the biggest mysteries in science boltzman saw that atoms could reveal why the second law of Thermodynamics was true why nature was engaged in an irreversible process atoms had the power to reveal what entropy really was and why it must always increase boltzman understood that all objects these walls you me the air in this room are made up of much tinier constituents basically everything we see is an assembly of trillions and trillions of atoms and molecules and this was the key to his insight about entropy in the second law boltzman saw what clausius could not the

real reason why a hot object left alone will always cool down imagine a lump of hot metal the atoms inside as are jostling around but as they jostle the atoms at the edge of the object transfer some of their energy to the atoms in the surface of the table these atoms then bump into their neighbors and in this way the heat energy slowly and very naturally spreads out and disperses the whole system has gone from being in a very special ordered state with all the energy concentrated in one place to a disordered state where the

same amount of energy is now distributed among many more atoms boltzman's brilliant mind saw this whole process could be described mathematically bolman's great contribution was that although we can talk in rather sort of casual terms about things getting worse and disorder increases the the great contribution of boltzman is that he could put numbers to it and so he was able to derive a formula which enabled you to calculate the disorder of a [Music] system this is boltzman's famous equation it will be his enduring contribution to science so much so it was engraved on his tombstone

in Vienna what this equation means in essence is that there are many more ways for things to be messy and disordered than there are for them to be tied and [Music] ordered that's why left to itself the universe will always get [Music] Messier things will move from order to disorder [Music] it's a law that applies to everything from a Dro jug to a burning star a hot cup of tea to the products that we consume every [Music] day all of this is an expression of the universe's tendency to move from order to [Music] disorder disorder

is the fate of [Music] everything clausius had shown that something he called entropy was getting bigger all the time now boltzman had revealed what this really meant entropy was in fact a measure of the disorder of things energy is crumbling away is crumbling away now as we speak so the second law is all about um entropy increasing which is just a a technical way of saying that things get worse [Music] boltzman's passionate and romantic sensibility and and his belief in the power of mathematics had led him to one of the most important discoveries in the

history of science but those very same intense emotions had a dark and ultimately self-destructive side throughout his life boltzman had been prone to severe bounce of depression sometimes these were induced by the criticisms of his theories and sometimes they just happened in 1906 he was forced to take a break from his studies in Vienna during a particularly bad [Music] episode in September 1906 boltzman and his family were on holiday in duino near triest in Italy while his wife and family were out at the beach boltzman hanged himself bringing his short time in our universe to

an abrupt end but perhaps the saddest aspect of boltzman's story is that within just a few years of his death his ideas that had been attacked and ridiculed during his lifetime were finally accepted what's more they became the new scientific Orthodoxy [Music] in the end there is no escaping entropy it's the ultimate move from order to Decay and disorder that rules us all boltzman's equation contains within it the mortality of everything from a China jug to a human life to the universe itself the process of change and degradation is unavoidable the second law says the

universe itself must one day reach a point of Maximum entropy maximum disorder the universe itself must one day die [Music] for [Music] if everything degrades if everything becomes disordered you might be wondering how it is that we exist how exactly did the universe manage to create the Exquisite complexity and structure of life on Earth contrary to what you might think it's precisely because of the second law that all this exists the great disordering of the COS Mo gives rise to its [Music] complexity it's possible to harness this natural flow from order to disorder to tap

into the process and generate something new to create new order new structure it's what the early steam Pioneers had unwittingly Hit Upon with their engines and it's what makes everything we deem special in our world from this car to buildings to works of art even to life [Music] itself the engine of my car like all engines is designed to exploit the second law it starts out with something nice and or Ed like this petrol stuffed full of energy but when it's ignited in the engine it turns this compact liquid into a mixture of gases 2,000

times greater in volume not to mention dumping heat and sound into the environment it's turning order into disorder what's so spectacularly clever about my car is that it can harness that dissipating energy it can siphon off a small bit of it and use it for a more ordered process like driving the Pistons which turn the wheels that's what engines do they tap into that flow from order to disorder and do something [Music] useful but it's not just cars Evolution has designed our bodies to work thanks to the very same principle if I eat this chocolate

bar packed full of nice ordered energy my body processes it and turns it into more disordered energy but powers itself off the proceeds both cars and humans power themselves by tapping into the great Cosmic flow from order to disorder although overall the world is falling apart in disorder it's doing it in a seriously interesting way it's like a um a waterfall that is rushing down um but the waterfall throws up a spray of structure and those that spray of structure might be you or me or daffodil or whatever so you can see that the unwinding

of the universe this collapse into disorder can in fact be constructive steam engines power stations life on Earth all of these things harness the cosmic flow from order to disorder [Music] the reason the earth now looks the way it does is because we've leared to harness the disintegrating energy of the universe to maintain and improve our small pocket of [Music] order but as humankind has evolved we've had to find New pieces of concentrated energy we can break down to Dr Drive the ever more demanding construction of our Technologies our cities and our society from food

to Wood to fossil fuels over human history we've discovered ever more concentrated forms of energy to unlock in order to flourish [Music] now in the 21st century we're on the cusp of harnessing the ultimate form of concentrated energy the stuff that powers the sun hydrogen this is the Colum Center for Fusion Energy in Oxford and at this facility they're attempting to recreate a star here on Earth but as you might imagine creating and containing a small star is not an easy process it requires many hundreds of people and some extremely ingenious technology this machine is

called called a toac and it's designed to extract an ancient type of highly concentrated energy the ordered energy of hydrogen [Music] atoms these tiny packets of energy were forged in the early Universe just 3 minutes after the moment of creation [Music] itself Now using the toac we can extract the concentrated energy contained in these atoms by fusing them together inside the toac machine two types of hydrogen gas dyum and tritium are mixed together into a super hot State called a plasma now when running this plasma can reach the incredible temperature of 150 million de large

mag maget in the wall of the toac contain the plasma and stop it from touching the sides where it can cool down now when it gets hot enough the two types of hydrogen atoms fuse together to form helium and spit out a neutron now these neutrons fly out of the plasma and hit the walls of the toac but they carry energy and the hope is that this energy can one day be used to heat up water turn it into steam to drive a turbine and generate electricity essentially for a brief moment inside the toac a

small donut-shaped star is [Music] created the problem is it's extremely difficult to sustain the fusion reaction for long enough to harvest the energy from it and that's what the scientists column are working to perfect it's a it's a sort of boundary between physics and Engineering how do we hold on to this very very hot thing which is the plasma and and and and how do we optimize the way the performance of this plasma so what we really want is that the particles stay in there for as long as all possible to maximize their CH chance

of hitting each other we are trying to push this this to the limits with what we have available in this machine and whatever we can learn to understand this plasma better will also allow us to design a better machine in the future and see although it happens several times a day oh here we go the the scientists here all all gather around the screens ah okay it's about to come on [Music] [Music] what the toac is doing is mining the fertile ashes of the Big Bang extracting concentrated energy captured at the beginning of time as

hydrogen is the most abundant element in the universe if future machines can sustain Fusion reactions they offer us the possibility of almost unlimited [Music] energy from a science that began as the byproduct of questions about steam engines thermodynamics has had a staggering impact on all our lives it has shown us why we must consume concentrated energy to stay alive and has revealed to us how the universe itself is likely to end looking at the Earth at night reveals how one seemingly simple idea transformed the planet [Music] over the past 300 years we've developed ever more

ingenious ways to harness the concentrated energy from the world around us but all our efforts and achievements are quite insignificant when viewed from the perspective of The Wider universe as far as it's concerned all we're doing is trying to preserve this tiny pocket of order in a cosmos that's falling [Music] apart although we can never Escape our ultimate fate the laws of physics have allowed us this brief beautiful creative moments in the great Cosmic unwinding my hope is that by understanding the universe in ever greater detail we can stretch this moment for many millions maybe

even billions of years to come [Music] the concept of information is a very strange one it's actually a very difficult idea to get your head round but in the journey to try and understand it scientists would discover that information is actually a fundamental part of our [Music] universe and there's more big science here on bbch HD at 7:00 tomorrow with the science of chance in Tales you win [Music] [Applause] [Music]