A note on the Einstein equation in string theory
我眼中的爱因斯坦英文作文
我眼中的爱因斯坦英文作文下载温馨提示:该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。
文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by theeditor. I hope that after you download them,they can help yousolve practical problems. The document can be customized andmodified after downloading,please adjust and use it according toactual needs, thank you!In addition, our shop provides you with various types ofpractical materials,such as educational essays, diaryappreciation,sentence excerpts,ancient poems,classic articles,topic composition,work summary,word parsing,copyexcerpts,other materials and so on,want to know different data formats andwriting methods,please pay attention!Albert Einstein, a name that is synonymous with genius and innovation. His contributions to the field of physics have revolutionized our understanding of the universe. But what truly fascinates me about Einstein is not just his scientific achievements, but his curiosity and passion for knowledge. He was a relentless seeker of truth, always questioning and challenging the status quo.Einstein's famous equation, E=mc^2, is perhaps the most well-known formula in the world. It represents the equivalence of mass and energy, a concept that has profound implications for our understanding of the universe. But what I find most inspiring about this equation is not just its mathematical elegance, but the fact that it emerged from Einstein's deep intuition and imagination.Einstein's theory of relativity is another groundbreaking idea that has reshaped our understanding of space and time. It challenges our conventional notions ofreality and forces us to think in new and unconventional ways. What I admire most about Einstein is his ability to think outside the box and imagine possibilities that were previously unimaginable.Einstein's personal life is also a source ofinspiration for me. Despite facing numerous obstacles and setbacks, he never gave up on his dreams. He remained committed to his work and continued to pursue his passion for knowledge, even in the face of adversity. This resilience and determination are qualities that I strive to emulate in my own life.In conclusion, Albert Einstein is not just a scientific icon, but a symbol of intellectual curiosity, imagination, and perseverance. His legacy continues to inspire and motivate countless individuals to push the boundaries of what is possible. Einstein's impact on the world extendsfar beyond the realm of physics, serving as a reminder that with passion and dedication, anything is possible.。
爱因斯坦的贡献英语
爱因斯坦的贡献英语Albert Einstein, a renowned physicist, revolutionized our understanding of the universe with his groundbreaking contributions to science. His most significant achievement was the development of the theory of relativity, which transformed our comprehension of space, time, matter, and energy.The special theory of relativity, published in 1905, established that the laws of physics are the same for all observers moving at constant speeds, regardless of their reference frame. This theory also introduced the concept of relativity of simultaneity, demonstrating that events that are simultaneous for one observer may not be simultaneous for another. Additionally, Einstein's famous equation E=mc²emerged from this theory, which showed that mass and energy are equivalent and can be converted into each other.His later work, the general theory of relativity, published in 1915, described gravity as a curvature of space-time caused by the presence of matter and energy. This theory predicted the existence of gravitational waves and black holes, both of which have been subsequently observed and confirmed. The theory also provided the foundation for modern cosmology,explaining the expansion of the universe and the origin of the Big Bang.Beyond his contributions to relativity, Einstein also made significant advancements in the field of quantum physics. His work on the photoelectric effect led to the development of quantum theory and earned him the Nobel Prize in Physics in 1921.Moreover, Einstein was not just a brilliant scientist; he was also a passionate advocate for peace and social justice. He actively campaigned for international cooperation and understood the potential dangers of nuclear weapons, warning against their development and use.In conclusion, Einstein's contributions to science and society are immeasurable. His theories and insights have transformed our understanding of the universe and continue to inspire generations of scientists and thinkers worldwide.。
the nature of scientific reasoning
本次翻译练习的难度比较大，文章出自北京师范大学研究生英语阅读与翻译课程所用的授课材料，作者布洛诺夫斯基是英国著名的数学家和散文家，剑桥大学数学博士。
这篇文章从科学发展史的角度出发，论述的问题主要是科学并不排斥想象力和创造力。
因此标题翻译成“科学理性的本质”或“科学推理的本质”是比较恰当的。
要翻译好这篇文章不仅应在在宏观的层面牢牢把握文章的主旨，也需要从微观的角度考虑作者使用的语言在语法和修辞上的特点，这样才能在理解的基础上恰当的表达。
当然，这篇文章相对于大家目前的英语水平，在理解和表达两个方面都具有不小的挑战性。
下面通过对这次翻译比较好的赵新平同学作业的点评，来分段落说一说这篇文章究竟有哪些细节部分需要注意，以及相应的翻译策略。
1What is the insight in which the scientist tries to see into nature? Can it indeed be called either imaginative or creative? To the literary man the question may seem merely silly. He has been taught that science is a large collection of facts; and if this is true, then the only seeing which scientists need to do is, he supposes, seeing the facts. He pictures them, the colorless professionals of science, going off to work in the morning into the universe in a neutral, unexposed state. They then expose themselves like a photographic plate. And then in the darkroom or laboratory they develop the image, so that suddenly and startlingly it appears, printed in capital letters, as a new formula for atomic energy.原译：什么是洞察力？科学家一直试图弄清它的本质。
爱因斯坦的生死方程式
In 1939, on the eve of the Second World War,Albert Einstein wrote a letter to theAmerican President, Franklin Roosevelt.Sir, the element Uraniummay be turned into a new andimportant source of energyin the immediate future.Certain aspects of the situation which hasarisen seem to call for watchfulnessand, if necessary, quick action onthe part of the administration.Extremely powerful bombs of anew type may thus be constructed.The letter was about an applicationof Einstein's famous equation,e=mc².And his fear that the Nazis could useit to build an atomic bomb.His letter set off a chain of events which led tothe destruction of Hiroshima and Nagasaki.Albert Einstein would later describe writingthis letter as the one mistake of his life.This is the story of his famous equation.And how e=mc² changed history and Einstein forever.On the eve of Second World War Albert Einstein,the most famous scientist in the world,was on holiday by the coast outside New York.He was an instinctive pacifistwho had fled Nazi Germany,and he had hoped to turn his backon the violence in Europe,and continue his work in peace.But his summer was interrupted bya visitor who had also fled the Nazis.The caller was Leo Szilard, another brilliant scientist and an old friend of Einstein's from Europe.Szilard.Herr Professor, there is something we must do.Come in.Leo Szilard had come to persuade his old friendthat the world was threatenedby a new weapon.His aim was to convince Einsteinthat something had to be done.Cookie?Herr Professor, I need your help.Why? Are you on the run from the police?I wish it was that simple. I wantyou to help me compose a letter.It's a long way to come for helpwith your correspondence.Not this correspondence. I've neverwritten a letter like this before.I'm not even sure what I should say.Who is the letter to?Roosevelt.President Roosevelt. Are you offeringadvice, or admonition?A warning. I want to warn Rooseveltabout the German bomb.The Germans have many bombs.Not one like this. At least, not yet.It's an atomic bomb, the Germans aregoing to be able to build an atomic bomb.And if they are doing it, then so must we.This meeting would one day come to haunt Einstein.Because Leo Szilard had come to explainthat the Nazi project he feared so muchwas an application of somethingEinstein himself had discovered,the equation e=mc².E=mc² is the symbol of Einstein's genius.It's an equation that sums up one of themost powerful truths about the universe.It combines two ideas, whichuntil Einstein came along,no one had ever dreamed could beconnected in such a powerful way.The idea of Mass.And the idea of energy.If you think about energy and massit is not at all obvious that they'reanything like the same thing.I mean energy is something that moving objects have,and mass is something that every object possesses.So really it's a bold step to try and link them in any way, let alone in a beautiful way that Einstein did.Einstein's great insight was that energy, thething that enables an object to move,and mass, essentially an objects weight,are not different, they are in fact the same thing.Einstein really found that energy andmass are two sides of the same coin.They're almost the same thing, so mass ina sense is energy waiting to be liberated.In other words, according to Einstein,mass could be transformed into energy.And energy into mass.But Einstein's equation went even further.It gave an exact value to the amount ofenergy contained within any given mass.Energy equals mass times C -the speed of light, squared,a number that is absolutely huge.This is Einstein's famous equation: e, energyequals m, mass, times c squared, the speed of light squared. In metres per second:eighty nine thousand, eight hundred andseventy five million million, huge number.That means you get an awful lot of energyfor an extremely tiny amount of mass.The implications of this neat equation were vast.Well it means that there's enoughenergy in a glass of waterto power a city like London for a week.Hidden within every object aroundus is a huge store of energy.Einstein published e=mc² in 1905.And it changed the world.It wasn't long before e=mc² solved oneof the great mysteries of life on earth.What really powers the sun?For generations this had baffled scientists.Because if the sun just burned like a huge bonfire,the calculations showed it should havedied out millions of years ago.But Einstein's equation explainedwhat was powering the sun.In the sun's core, mass was constantlybeing converted into energy.A process that can be sustained for billions of years.Tiny particles were smashing together,and the mass lost in this reactionwas transformed into energy.And soon people began to think,if e=mc² can power the sun,could we use it to generate power on earth?Could we release the energy insideatoms for our own purposes?Within years, talk of getting energy out of theatom began to grip the popular imagination.And at a scientific conference in 1935,Einstein was asked whether he thoughtthe atom would ever yield its energy.His answer was to go down in scientific history.The likelihood of transforming matter into energyis something akin to shooting birds in the darkin a country in which there are very few birds.In other words, Einstein believedgetting energy out of the atomwas just not practical.It would take an almost incalculable amount of energy to release energy even from even a single molecule. Einstein was so dismissive becauseit was becoming clearthat to release all that energyscientists would have to find an efficientway of breaking the atom apart.And however hard they tried,it always took more energy to smashan atom than was released.Kinda tough, huh?Kind of tough, yes.But others were less dismissive.In 1933 Hitler came to power in Germany.Germany was one of the great centres of physics. Some of its scientists were onlytoo willing to work with Nazis.And the Nazi war machine was eager toachieve what Einstein had said was impossible,to release energy from theatom, and create a bomb.Unlike Einstein, Leo Szilard feared thatenergy could be released from the atomaccording to e=mc², and thenused to construct a bomb.And that fear had taken him to seeEinstein that summer in Long Island.The war in Europe is going to happen. Hitler has planned for it. And he has built up his arms.And once he realises its power, he willnot hesitate to construct an atomic bomb.But that would take years.Why years?To build such a bomb the reactionwould have to take placein multiple millions of atoms simultaneously. Maybe not simultaneously.I think maybe there is anotherway that might be achieved.Szilard was speaking with such confidencebecause he knew something Einstein did not.Leo Szilard had worked outhow to make e=mc² into a bomb.In 1920, a young Leo Szilardhad gone to study in Berlin.There he witnessed the rise of the Nazis.Szilard became worried by what thismight mean for science and for the world.Szilard was really scared because hehad seen the Nazi terror first hand.He warned his colleagues and then hehimself left shortly after Hitler took power.He was trying to draw as many friendsas he could out of Nazi Germany,he saw how the terror was spreading.But many brilliant physicists remained in Germany, and Szilard was fearful itwas only a matter of timebefore someone would find a wayof harnessing the power of e=mc²and make a bomb.In fact, the first step had alreadyinadvertently been taken,scientists had identified the type of substance they might need to turn mass into energy.Yes radioactivity is alreadyat work in medical fields...Radioactive iodine.so if you will listen and watch at thesame time when we hear the clicks.Radioactivity is e=mc² in action.Unstable elements like Radium andUranium continually break downinto ever smaller elements inorder to become more stable.What is actually happening is that tiny amountsof mass from the heart of an unstable atomare spontaneously released in the form of energy,which is carried away as radiation.But finding the right type of substanceto release energy according to e=mc²was only half the answer.This scintillating character is very unstable, andas a consequence she radiates energy.We call her radioactive.Natural radioactivity was originallythought to be potentially very useful.But the more that was understood about it,it was realised that this particular formof radioactivity whilst producing heatwas not especially efficient.The amount of heat given out was rather small.This is radioactive iodine.I'm now going to drink this.Natural radioactivity was simply far toogentle for generating real power.So scientists began to develop ways of improving upon nature. In Germany, in Britain and in Americamachines were built to achieve nuclear fission,the splitting open of the atomic nucleus.Many hoped this might releasethe vast amounts of energypotentially hidden within the atom.Initially hopes were high, but againand again they hit Einstein's paradox.They always had to put in far moreenergy than they ever got out.The likelihood of transforming matter into energyis something akin to shooting birds in the darkin a country in which there are only very few birds.It looked as though Einstein had been right after all.e=mc² was simply a theoretical insight,not a practical solution to generatingvast amounts of energy.But then Einstein's friend, LeoSzilard had his first brainwave.It happened day in 1933.He suddenly realised everyone hadbeen going about it the wrong way.Attempts to release energy from matter hadinvolved something called alpha particles.And Szilard thought they were simplythe wrong tool for the job.Alpha particles consist of2 protons and 2 neutronsand carry a positive electric charge.The theory was that by smashingthese particles at the nucleusthey might blast it apart, converting some of the mass into energy.It turned out to be not enough.And even when the developments proceededand accelerators were made to accelerate thealpha particles to higher and higher energies,still it needed more energy putting in thanyou actually got out from the process.Leo Szilard recognized the problemwas down to an invisible force,the positive charge of the alpha particle.Because the nucleus of the targetatom is also positively charged,just as magnet can repel each other,the identical positive charges of the nucleus andthe alpha particle would also repel each other.It was this clash of electrical chargethat was preventing the alpha particlefrom blasting apart the nucleus.Alpha particles themselvescarry a positive electric charge.The nucleus has a positive electric chargeso the two repelled each otherand every time an alpha particleis sent towards the nucleus,it has a tendency to slew off to one side or the other. Szilard realised what was neededwas a particle able to attack thevery heart of the charged nucleus.And he thought he knew what would do it,the recently discovered neutron.The neutron is a subatomic particle, justa quarter of the mass of an alpha particle.And it has no electric charge.Szilard reasoned that if a neutroncould be fired at an atom's nucleus,it would not be repelled.Instead it might bond to the nucleus itself.And then the nucleuswould become very unstable.It might then split.And as it did so,it could release some of its vaststore of energy, according to e=mc².This was quite a stupendous discovery.The neutron carried no electric chargeand therefore it could approachthe nucleus un-deflectedand maybe even stick and interact with it.In fact the impact of the neutronon the nucleus at the timewas likened to the effect ofthe moon striking the earth.Here was a means perhaps to makethis slightly wobbly unstable nucleusabsorb something that it couldn't help absorbingand then it would wobble even more and disintegrate.Using the neutron was simplySzilard's first brainwave.He went on to have another,one that would become crucial tothe making of the atomic bomb.Szilard calculated that if you hitan atom with a neutron,as the atom divided, it would release not justenergy, but two or three more neutrons.And those neutrons might then befree to break apart further atoms.And every time that happened a tiny bit of masscould be converted into a vast amount of energy.Energy that at every step in the chain, would multiply and multiply. It was a chain reaction.So typically you would end up withtwo extra neutrons coming out.So those two extra neutrons couldthen produce another fission processand produce two more neutrons,so you have 4 neutrons,that would then go to 8,16,32.You have this multiplicative chain reaction process and the potential for that was immediately seen because each of these processesproduces a large amount of energy.What made Leo Szilard's idea so brilliantwas that here, for the first time, was a wayof getting energy out of the atom,without having to pump in vast amounts of power.All you had to do was setoff just one tiny neutronto trigger an unstoppable chain reaction.Leo Szilard had potentially found a way tounleash the power of e=mc² on Earth.But it was a discovery that terrified him.Szilard's first reaction whenhe thought of the neutron wasthis is something that couldbecome potentially a weapon.His second thought was that ifhe could think of thisthen certainly his German colleagues whoremain in Germany could think of it tooand this really scared him.Then, in 1938, less than a year beforethe outbreak of World War II,news came from his former colleagues in Germany,news that truly alarmed Leo Szilard.Scientists from several nationsgathered for a routine conferenceheard a report of startling significance.Word has just come through fromGermany by way of Denmarkthat the German Physicists Hahn and Strassmanhave just verified that the uraniumatom under neutron bombardmentactually splits in to two parts.In a lab in Berlin, the German team had struck lucky. They had achieved nuclear fission,the first stage of Szilard's theoretical chain reaction. In terms of physics it wasan enormous breakthroughbecause up until that point it wasa theory and theories are greatbut they need to be verified experimentallyand it was the experimental verification of thatwhich was really was the groundbreaking thingwhich meant wow this theory is true.Within months, the Nazisbegan to stockpile Uranium.They would later set up amilitary bomb programme.Nazi money poured into fission research.Nuclear physics was going to war.For Leo Szilard, it was no longerpossible for science to be neutral.You are a scientist. As am I.It is best to remember that andlet the military play their games.I don't think that we can.Not when some of our former colleagues in Germanyare only too happy to work with the military.That is their choice, if they wish to be so foolish. They are still good scientists. Some of the best.And the military will give themall the assistance they need,but we also have good scientists.Also some of the best.So now you want us to go to war in the laboratory?That was precisely whatLeo Szilard wanted to do.The German scientists had achievedthe first part of Szilard's theory,nuclear fission with neutrons,and now he had to determine if theother stages of the process would follow.By July 1939 in a lab at Columbia University,Szilard with his colleague Enrico Fermihad conducted an experiment,that showed a chain reaction was possible.There was now a real chance that e=mc²could be harnessed to make a bomb.Szilard realised the fate of Mankindwas now in the hands of science.So he decided to use the fame and influenceof the most eminent scientist of the ageto alert the free world to thelikelihood of a Nazi atomic bomb.And that was why in July 1939,he called on his old friend.Szilard's mission was to show Einsteinthat the formula he had thought up in 1905,e=mc²,had a new and terrible realitywith the element uranium.30100:30:07,805 --> 00:30:12,394Szilard had always been someone who believedhe had the mission of saving the world.30200:30:12,905 --> 00:30:16,226And here abruptly through a scientific discovery 30300:30:16,765 --> 00:30:21,061was a very practical situation wherethe world might need saving.30400:30:21,259 --> 00:30:22,209Herr Professor.30500:30:23,463 --> 00:30:25,700I need your help.30600:30:27,435 --> 00:30:30,390It's a lot to have in your headas you knock on a door.30700:30:35,390 --> 00:30:38,941Szilard had come to tell Einstein about his recent work on the chain reaction,30800:30:40,880 --> 00:30:45,081and that this breakthrough meant abomb was now a real possibility.30900:30:46,496 --> 00:30:48,737Daran habe ich gar nicht gedacht.31000:30:50,031 --> 00:30:51,982I hadn't thought of that.31100:30:52,455 --> 00:30:56,639Sometimes I think I have thought of littleelse. Certainly not for the past six years.31200:30:57,257 --> 00:31:00,009A secondary neutron reaction.31300:31:00,711 --> 00:31:04,173Multiple neutrons splitting multiple atoms and continuing. 31400:31:07,256 --> 00:31:13,358Multiple neutrons splitting, multipleatoms, and continuing.31500:31:15,842 --> 00:31:18,814You are sure the chain reaction could be sustained?31600:31:19,227 --> 00:31:21,316That's what Fermi and I have been working on.31700:31:21,948 --> 00:31:27,063So, so the release of energy would multiply,31800:31:28,307 --> 00:31:31,221the reaction would be enormous, just imagine.31900:31:31,569 --> 00:31:32,919I know.32000:31:34,264 --> 00:31:38,211But just imagine, just imagine this.32100:31:40,832 --> 00:31:46,342Say if an atomic device was introduced into, say,32200:31:48,094 --> 00:31:49,506New York,32300:31:50,535 --> 00:31:55,088say such a bomb was taken into NewYork Harbour in the hold of a ship.32400:31:57,523 --> 00:31:59,423And say it was detonated.32500:32:01,753 --> 00:32:03,824What would the destruction be?32600:32:09,925 --> 00:32:15,712And soon such a bomb could bein the possession of Herr Hitler.32700:32:17,723 --> 00:32:19,896What should we say in this letter?32800:32:21,676 --> 00:32:25,473Once Einstein heard about this he thought about it 32900:32:25,879 --> 00:32:28,364and within a few minutes he realised 'yes,33000:32:29,159 --> 00:32:31,899this is what e=mc² means'.33100:32:32,213 --> 00:32:36,137At that point his abstract pacifism, if you will, 33200:32:36,554 --> 00:32:38,830would have become an intensely practical question, 33300:32:39,114 --> 00:32:42,644'What can I personally do to limit somehow33400:32:42,857 --> 00:32:45,853the possibility that these mencould work on this weapon'.33500:32:50,211 --> 00:32:54,008The famous pacifist now began towrite a letter to the President.33600:32:54,169 --> 00:32:57,905In the last four months it has been made probable (337)Calling for America to build the mostpowerful weapon ever constructed.33800:33:04,098 --> 00:33:09,442...to set up a nuclear chain reaction,in an amount of uranium.33900:33:09,849 --> 00:33:10,948Bigger.Huh?34000:33:11,655 --> 00:33:16,047Bigger, a... large mass... a large mass of uranium.34100:33:16,659 --> 00:33:18,347It is conceivable, so much is certain34200:33:19,031 --> 00:33:23,120that an extremely powerful bomb of a new type may thus be constructed. 34300:33:23,763 --> 00:33:24,969How powerful?34400:33:25,233 --> 00:33:26,672You know how powerful.34500:33:26,973 --> 00:33:31,374Would Roosevelt? Should we not make itplain that this will be no ordinary bomb?34600:33:31,903 --> 00:33:34,535Yes, yes we should.34700:33:37,704 --> 00:33:41,422It is almost certain that thiscan be achieved in the future.34800:33:42,392 --> 00:33:44,584Too hazy, 'the future'.34900:33:45,101 --> 00:33:48,157We need to say that the Germans can get it at any time.350I believe therefore it is my duty to bring to your attention 35100:33:55,738 --> 00:33:59,344the following facts and recommendations.35200:34:03,782 --> 00:34:08,501Yours, very truly, Albert Einstein.35300:34:20,466 --> 00:34:24,536Eight weeks later Albert Einstein'sletter was taken to the White House.35400:34:27,687 --> 00:34:30,632I think that any letter written by Albert Einstein35500:34:31,201 --> 00:34:33,598would get a President's attention.35600:34:35,478 --> 00:34:37,525Roosevelt's reaction was,35700:34:38,537 --> 00:34:41,775'so you're afraid that theNazis are going to blow us up'.35800:34:44,143 --> 00:34:48,681'Yes'. In that case he called inhis military aide and he says35900:34:48,960 --> 00:34:51,481this demands action.36000:34:54,319 --> 00:34:57,969It was now question of who wouldbuild an atomic bomb first,36100:35:00,904 --> 00:35:05,280the Americans or the Nazis.36200:35:16,581 --> 00:35:18,204In the wilderness of New Mexico,36300:35:18,967 --> 00:35:23,820the US government set up a top-secretproject codenamed 'Manhattan'.36400:35:30,130 --> 00:35:31,253From Einstein's letter36500:35:31,806 --> 00:35:35,548grew the biggest and most remarkable collaborationbetween science and the military36600:35:36,369 --> 00:35:38,187the world has ever seen.36700:35:42,325 --> 00:35:46,219The government spent something like 2.2 billion dollars,36800:35:46,775 --> 00:35:51,601which translated into modern dollars wouldbe perhaps 40 or 50 billion dollars.36900:35:52,487 --> 00:35:55,559As much as it would later costtoo send a man to the moon.37000:35:56,726 --> 00:36:01,756It was considered absolutely vital tothe security of the allied forces.37100:36:06,838 --> 00:36:12,055The Manhattan project brought together someof the finest minds physics has ever produced.37200:36:15,002 --> 00:36:18,860Among them were many European scientists who had fled the Nazis,37300:36:19,511 --> 00:36:21,007including Leo Szilard.37400:36:21,999 --> 00:36:24,921Einstein himself played no part.37500:36:28,975 --> 00:36:33,060The scientists were driven by the fear that the Nazis might get there first.00:36:37,044 --> 00:36:40,384But in May 1945 before the bomb was complete37700:36:41,876 --> 00:36:43,913all the calculations changed.37800:36:55,219 --> 00:36:57,229The Nazis surrendered.37900:36:57,654 --> 00:37:01,973On behalf of the army of the UnitedStates I accept your surrender.38000:37:02,183 --> 00:37:04,428The war in Europe was now over.38100:37:13,343 --> 00:37:16,196For some of the Manhattan projectscientists, and for Einstein,38200:37:16,965 --> 00:37:22,564there could now be no justification for the US to use an atomic weapon against anyone else.38300:37:24,534 --> 00:37:28,874Most of the scientists were idealists andsome of them were very naive idealists.38400:37:29,302 --> 00:37:31,597Einstein was probably one of those.38500:37:32,619 --> 00:37:36,137He really was thinking in terms of a deterrence, 38600:37:36,573 --> 00:37:39,361trying to keep Germany from using this bomb.38700:37:40,978 --> 00:37:43,016But although there was no longerany threat from the Germans,38800:37:43,769 --> 00:37:46,249work at Los Alamos continued.00:37:52,425 --> 00:37:58,272And in July 1945, two months after theNazi defeat, the bomb was ready.39000:38:00,466 --> 00:38:03,709The bloody war against Japan was still raging.39100:38:05,874 --> 00:38:08,869And the generals and politiciansbelieved that the atomic bomb39200:38:09,397 --> 00:38:13,941could bring about a swift end to thefighting and save thousands of allied lives.39300:38:17,650 --> 00:38:20,257Leo Szilard was horrified thatthe bomb might be dropped39400:38:20,970 --> 00:38:23,697without a specific warning first being given.39500:38:25,408 --> 00:38:30,408He organised a petition among his colleagues,calling on the President to give this warning.39600:38:33,815 --> 00:38:37,385But there was now no stopping the use of the bomb.39700:38:37,584 --> 00:38:41,066They'd spent lots of money, they had a weaponthat could win the war very quickly,39800:38:41,812 --> 00:38:44,011and in that sort of situation they were going to use it. 39900:38:48,216 --> 00:38:49,770The target had been selected,40000:38:52,045 --> 00:38:54,073the Japanese city of Hiroshima.40100:39:03,744 --> 00:39:08,274On a bright morning in August 1945,the first atomic bomb was dropped.40200:39:14,361 --> 00:39:17,203It fell through the air for 43 seconds.40300:39:17,836 --> 00:39:21,744And then a single neutronstarted Szilard's chain reaction.40400:39:23,579 --> 00:39:26,293The energy released as the firstatom of Uranium was split40500:39:28,589 --> 00:39:30,592was only enough to make a grain of sand jump.40600:39:32,428 --> 00:39:36,088Then the chain reaction became unstoppable.40700:39:56,084 --> 00:39:58,100By the final generation of the chain reaction40800:39:58,618 --> 00:40:04,559around two million million million millionuranium atoms have been fissioned.40900:40:05,372 --> 00:40:08,664About point 6 grams of mass have been converted 41000:40:08,905 --> 00:40:12,884into a massive 12.5 kilotonnes of energy41100:40:13,326 --> 00:40:15,962in just six tenths of a microsecond.41200:40:16,594 --> 00:40:22,136That's the power of a chain reaction and of e=mc². 41300:40:25,732 --> 00:40:28,672Just point six of a gram of massconverted into energy41400:40:29,754 --> 00:40:31,590。
爱因斯坦英文介绍
A lonely boy
Einstein was born on March 14, 1879. At his birth, his mother felt the son was a little unusual. His head was large, and the shape was strange. The time he used to learn to speak was much longer than other children. At that time, his parents felt their son may be stupid, but it turned out that he had such a great success.
in school.
3. 一个人从未犯错是因为他不曾尝试新鲜事物。 Anyone who has never made a mistake has never tried
anything new.
4. 态度上的弱点会变成性格上的弱点。 Weakness of attitude becomes weakness of
A wise teacher
At sixteen Einstein applied for ETH（瑞士苏黎世 的联邦工业大学）, but the entrance examination ended with failure. Mr. Weber read his papers of mathematics and physics and praised him: “You are a very intelligent child, Einstein, a very smart child, but you have a big drawback （缺点） that you do not want to express yourself."
形容爱因斯坦的英语单词
形容爱因斯坦的英语单词Einstein: The Genius of Our TimeAlbert Einstein, hailed as one of the greatest minds in history, is an iconic figure whose contributions to science and humanity are immeasurable. Known for his groundbreaking theories and discoveries, Einstein revolutionized our understanding of the physical world and left an indelible mark on the fields of physics and mathematics. In this article, we will explore several English words that aptly describe the brilliance, intellect, and enduring legacy of Albert Einstein.1. GeniusEinstein's name is synonymous with genius. Throughout his life, he showcased exceptional intellectual abilities and displayed an extraordinary aptitude for problem-solving. His groundbreaking theory of relativity, which challenged the fundamental principles of classical physics, demonstrated his exceptional brilliance and creative thinking. The word "genius" encompasses his ability to think outside the box and question established theories, leading to paradigm-shifting advancements in scientific knowledge.2. VisionaryEinstein's visionary ideas surpassed the boundaries of his time. His imagination and foresight allowed him to explore uncharted territories in the world of physics. His ability to conceive of radical theories and anticipate future scientific developments sets him apart as a true visionary. Einstein's belief in the unity of the universe, encapsulated in his famous equationE=mc², revealed his profound understanding of the interconnections between different branches of science.3. RevolutionaryEinstein's theories and discoveries completely transformed the realm of physics. His theory of relativity, formulated in the early 20th century, challenged the Newtonian worldview and introduced an entirely new understanding of space and time. This revolutionary breakthrough paved the way for further advancements in physics and laid the foundation for modern cosmology. Einstein's work shattered conventional thinking, propelling the field of physics into new and unexplored territories.4. IntellectualEinstein's intellectual capacity was unparalleled. He possessed an insatiable curiosity and a thirst for knowledge that drove him to investigate the fundamental workings of the universe. Throughout his career, he engaged in rigorous scientific research, published numerous papers, and exchanged ideas with fellow intellectuals. His intellectual prowess amazed and inspired his peers, establishing him as a leading figure in the scientific community.5. PerseveranceEinstein's journey towards scientific greatness was marked by perseverance and unwavering determination. Despite facing setbacks and challenges, he remained committed to his research and continued to push the boundaries of scientific understanding. His significant contributions tophysics were the result of his relentless pursuit of knowledge and his refusal to give up in the face of adversity.6. LegacyEinstein's legacy extends far beyond his scientific achievements. His profound impact on society and culture earned him a revered place in history. His views on social justice, pacifism, and human rights resonate to this day. The word "legacy" encompasses his enduring influence, which transcends the realm of science and serves as an inspiration for future generations.In conclusion, Albert Einstein's remarkable intellect, visionary thinking, and groundbreaking discoveries have earned him a place in the annals of history. Describing Einstein's genius, vision, revolutionary ideas, intellectual capacity, perseverance, and enduring legacy, the English words mentioned above offer a glimpse into the extraordinary life and contributions of this extraordinary scientist. Einstein's legacy continues to motivate and inspire scientists and thinkers worldwide, ensuring that his name will forever be associated with brilliance and innovation.。
爱因斯坦读后感50字英文
爱因斯坦读后感50字英文Here is an essay on the topic "Reflections on Einstein: 50 Words" with a word count over 1000:Einstein's revolutionary theories have profoundly shaped our understanding of the universe. His groundbreaking work on relativity challenged long-held beliefs and paved the way for transformative advancements in physics. Through his relentless pursuit of scientific truth, he has left an indeluring legacy that continues to inspire generations of thinkers and scholars. Einstein's genius and intellectual courage stand as a testament to the power of the human mind to unveil the mysteries of the cosmos. His life's work reminds us that the most profound insights often arise from daring to question the status quo and embracing the unknown. In just fifty words, we are left in awe of Einstein's towering achievements and the profound impact he has had on our comprehension of the physical world.The foundations of modern physics were laid by the work of Albert Einstein whose theories of relativity revolutionized our understanding of space time and gravity. His famous equationE=mc^2 demonstrated the equivalence of mass and energy andpaved the way for the development of nuclear technology. Einstein's scientific breakthroughs challenged classical notions of absolute time and space ushering in a new era of physics.Beyond his scientific accomplishments Einstein was also a passionate humanitarian who advocated for peace and social justice. He spoke out against the rise of Nazism in Germany and was a vocal opponent of nuclear weapons. Einstein believed that scientists had a moral obligation to use their knowledge to benefit humanity. His commitment to these ideals made him a revered public figure whose influence extended far beyond the realm of physics.What is most remarkable about Einstein's legacy is the manner in which he was able to blend his profound intellect with a deep sense of wonder and curiosity about the natural world. He possessed an unparalleled ability to conceptualize complex phenomena and render them into elegant mathematical formulations. Yet he never lost sight of the sheer beauty and mystery that lie at the heart of the universe. Einstein's work was fueled by a driving desire to uncover the fundamental principles that govern reality.The elegant simplicity of Einstein's groundbreaking theories belies the immense intellectual struggle and creativity required to formulate them. His breakthrough insights did not come easily but were the product of tireless experimentation, mathematical rigor,and a willingness to challenge prevailing orthodoxies. Einstein was unafraid to venture into uncharted territory trusting in the power of reason and empirical observation to reveal new truths.What is perhaps most inspiring about Einstein is how he was able to preserve his childlike sense of amazement in the face of the universe's wonders. He once wrote "the most beautiful experience we can have is the mysterious. It is the fundamental emotion that stands at the cradle of true art and true science." This ability to maintain a sense of awe in the face of the unknown is a testament to the profundity of Einstein's intellect as well as the depth of his humanity.In an era increasingly dominated by hyper-specialization and narrow fields of inquiry, Einstein's catholic interests and interdisciplinary approach offer a valuable lesson. He recognized that the most fruitful insights often emerge at the intersection of various domains of knowledge. His work seamlessly bridged the realms of physics, philosophy, and even the arts demonstrating the inherent unity of human understanding.The life and work of Albert Einstein stand as a testament to the power of the human mind to unravel the mysteries of the cosmos. His revolutionary theories have profoundly shaped our understanding of reality and continue to guide the march ofscientific progress. Yet Einstein's legacy transcends the realm of science alone. Through his passionate advocacy for peace and social justice, he has also inspired generations to harness the fruits of human knowledge in service of the greater good. In Einstein, we find a singular mind possessed of unparalleled intellectual gifts as well as a deep wellspring of humanitarian ideals. His is a legacy that will continue to captivate and inspire long into the future.。
用英语介绍爱因斯坦
Einstein’s theory of general relativity, published in 1915, expanded on his earlier work and provided a new understanding of gravity. The theory proposed that massive objects cause a distortion in space-time, which we perceive as gravity. This not only revolutionized our understanding of the universe, but it also made Einstein a global celebrity. In 1921, he was awarded the Nobel Prize in Physics for his work on the photoelectric effect, rather than his work on relativity, which was still considered controversial by many in the scientific community.
Great Minds: Einstein
Name: ______________________________Great Minds: Albert Einsteinby Lydia LukidisYou would probably recognize Albert Einstein from hisphotos. Yep, he was the guy with the crazy hair! But he alsohad some great ideas. He was more than just a scientist. Hewas a genius who changed our lives. He made some ofscience’s biggest discoveries. He also developed someimportant theories. Some of these theories may seemcomplicated. But they concern everybody. Science iseverywhere and affects us every day. Einstein’s discoveriesmade things like television, DVD players, and garage dooropeners possible.Einstein was born in Germany in 1879. When he wasfive years old, his dad gave him a compass. It became hisfavorite toy. He would stare at the needle of the compass asit moved. It seemed like magic at first. Einstein wanted to understand how the needle moved. So he learned about magnetism. Magnetism is about the invisible force of magnets. It can make objects stick together or move away. Einstein also learned a lot about science and electronics because of his dad. His dad owned an electronics company. It was no surprise that Einstein ended up loving math and science. He started performing experiments at a very young age.Einstein performed extremely well in school. He quickly advanced to higher level math and science topics, and his teachers were impressed by his grasp of college-level physics concepts by the time he was eleven. When he was young, he met a Polish medical student named Max Talmud. Talmud became his tutor. He showed Einstein a children’s textbook about science. Einstein became curious about light and other things.Einstein later attended school in Switzerland. He made many friendships. He also met his future wife, Mileva Maric. She was a Serbian physics student. Einstein received hisdoctorate in 1905. That same year, he published many important scientific papers.After that, Einstein became a professor in Germany. But times were tough back then. Hitler and his Nazi party started a war against Jewish people. Einstein was Jewish. So he decided to leave and go to the United States. That was in 1933. And it’s a good thing he did. The world needed him to be free and pursue his passions.Einstein was not an inventor like ThomasEdison or Alexander Graham Bell. But histheories and discoveries changed the waywe look at things. Some example aretime, space, matter, energy, and gravity.Einstein is best known for his Theory ofRelativity. You probably heard of theequation E=mc². E stands for energy, mstands for mass, and c stands for speed of light. But what does this all mean? Yes, it is as complicated as it sounds! Here’s the most basic way to explain it. The theory is a scientific explanation about how space relates to time. This was very important. It changed the way scientists looked at the universe. This theory also brought on inventions like the nuclear bomb and nuclear energy.Einstein made many other discoveries. For example, he figured out that light is made up of many little particles called photons. He called this the quantum theory of light. At the time, some other scientists did not agree with this theory. But later, it was proven. This was an important discovery. It led to many inventions such as television.Here’s one more example of an important discovery Einstein made. Along with scientist Satyendra Bose, he discovered a new state of matter. Regular states of matter are gas, liquid, and solid. Einstein and Bose found another one. They named it the Bose-Einstein Condensate. Today, it’s used in cool things like lasers.Einstein’s work was and is valuable to the world. This is one of the reasons he eventually won the Nobel Prize in Physics. The Nobel Prize is a very famous award given to someone who has done outstanding work in different subjects like science or medicine. Einstein died in 1955. He was later named “Person of the Century” by TIME Magazine.Great Minds: Albert Einsteinby Lydia Lukidis1. Based on the information in the article, which statement is trueabout Albert Einstein's younger years?a.Einstein's teachers were disappointed in his lack of interest in math and science.b.Einstein was tutored by a Polish medical student, Max Talmud.c.Einstein wanted to be a physics professor like his father.d.Einstein's first time traveling abroad was when he fled Germany for the U.S. in1933.2.Even though Albert Einstein wasn't an inventor, his discoveries paved the way for manyinventions. Name six things that were invented because of Einstein's work in math and science.1. ____________________2. ____________________3. ____________________4. ____________________5. ____________________6. ____________________3.Einstein is very famous for his Theory of Relativity. His equation, E=mc², is a scientificexplanation for how space relates to time. What does each part of the equation stand for?E - ____________________ m - ____________________ c - ____________________4. In addition to Einstein's Theory of Relativity, describe two other important discoveriesEinstein made during his life._____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ 5.What honor was bestowed on Albert Einstein later on in his career?_____________________________________________________________________________________Great Minds: Albert Einsteinby Lydia LukidisThe following terms are vocabulary words from the article. Match thevocabulary word with its correct definition by writing the correspondingletter on the line.1._____ genius a. a force that pulls a body toward the center of theearth2._____ century b. an instrument that displays the direction of magneticnorth3._____ theory c. complex; difficult to understand4._____ gravity d. eager to learn about or know something5._____ doctorate e. everything in existence; the cosmos6._____ complicated f. mastermind; brilliant person7._____ universe g. excellent; exceptional8. _____ compass h. a set of ideas that is intended to explain something9._____ curious i. the highest degree that is awarded by a college,university, or other institution of learning10. _____ outstanding j. a period of one hundred yearsGreat Minds: Albert Einsteinby Lydia LukidisIn the article, “Great Minds: Albert Einstein,” you learned that Einsteinwas awarded the Nobel Prize in Physics for his outstandingaccomplishments and scientific discoveries.Choose another recipient of the Nobel Prize in Physics. Tell who theperson is/was, what year he or she was awarded the prize, and briefly summarize his or her major accomplishments. If you use the Internet with your teacher's permission, write the web address of the website you used as a source on the bottom of the page.__________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ Internet Source Used: _____________________________________________________________________Great Minds: Albert Einsteinby Lydia Lukidis1. Based on the information in the article, which statement is trueabout Albert Einstein's younger years? ba.Einstein's teachers were disappointed in his lack of interest in math and science.b. Einstein was tutored by a Polish medical student, Max Talmud.c.Einstein wanted to be a physics professor like his father.d.Einstein's first time traveling abroad was when he fled Germany for the U.S. in1933.2.Even though Albert Einstein wasn't an inventor, his discoveries paved the way for manyinventions. Name six things that were invented because of Einstein's work in math and science.1. television2. DVD players3. garage door openers4. nuclear bomb5. nuclear energy6. lasers3.Einstein is very famous for his Theory of Relativity. His equation, E=mc², is a scientificexplanation for how space relates to time. What does each part of the equation stand for?E - energy m - mass c – speed of light4. In addition to Einstein's Theory of Relativity, describe two other important discoveriesEinstein made during his life.Einstein discovered that light is made up of photons. Einstein also discovered anew state of matter along with Satyendra Bose, called Bose-Einstein Condensate.5.What honor was bestowed on Albert Einstein later on in his career?He was awarded the Nobel Prize in Physics.Great Minds: Albert Einsteinby Lydia LukidisThe following terms are vocabulary words from the article. Match thevocabulary word with its correct definition by writing the correspondingletter on the line.1.f genius a. a force that pulls a body toward the center of theearth2.j century b. an instrument that displays the direction of magneticnorth3.h theory c. complex; difficult to understand4.a gravity d. eager to learn about or know something5.i doctorate e. everything in existence; the cosmos6.c complicated f. mastermind; brilliant person7.e universe g. excellent; exceptional8.b compass h. a set of ideas that is intended to explain something9.d curious i. the highest degree that is awarded by a college,university, or other institution of learning10.g outstanding j. a period of one hundred years。
用英语介绍物理学家爱因斯坦作文
用英语介绍物理学家爱因斯坦作文全文共3篇示例，供读者参考篇1Albert Einstein, a name that reverberates through the annals of history as one of the most profound and revolutionary physicists of all time. Born on March 14, 1879, in Ulm, Germany, Einstein is best known for his theory of relativity, which reshaped our understanding of space, time, and gravity.Einstein’s life and work are a testament to the power of curiosity, creativity, and perseverance. From a young age, he showed a keen interest in math and science, questioning the fundamental principles of the universe. After graduating from the Swiss Federal Institute of Technology in Zurich, Einstein began working as a patent clerk in Bern, Switzerland, where he continued to develop his groundbreaking theories in his spare time.In 1905, Einstein published four papers that would change the course of physics forever. These papers laid the foundation for his special theory of relativity, which posited that time and space are not absolute, but are instead intertwined in afour-dimensional continuum known as spacetime. This theory fundamentally altered our understanding of the nature of the universe, challenging centuries-old assumptions about the nature of reality.Building on the success of his special theory of relativity, Einstein went on to develop his general theory of relativity in 1915. This theory extended the principles of special relativity to include the effects of gravity, showing that massive objects like planets and stars can warp the fabric of spacetime, causing objects to follow curved paths through space. General relativity has since been confirmed through numerous experiments and observations, cementing Einstein’s reputation as one of the greatest physicists of all time.In addition to his work on relativity, Einstein also made significant contributions to the field of quantum mechanics, the study of the behavior of particles on the tiniest scales. His work on the photoelectric effect, for which he was awarded the Nobel Prize in Physics in 1921, helped to lay the groundwork for the development of quantum theory.Throughout his life, Einstein’s work was guided by a deep commitment to peace, social justice, and human dignity. He was a passionate advocate for civil rights, pacifism, and disarmament,using his fame and influence to speak out against war, racism, and intolerance. He believed that science and reason could be used to build a better world for all people, and he never wavered in his commitment to promoting the values of tolerance, compassion, and understanding.Today, Ein stein’s legacy lives on in the countless scientists, scholars, and thinkers who continue to be inspired by his work. His ideas have reshaped our understanding of the universe and continue to push the boundaries of human knowledge. While Einstein may be gone, his spirit of curiosity, creativity, and compassion lives on in all those who strive to unlock the mysteries of the cosmos and make the world a better place for future generations.篇2Albert Einstein, a physicist who revolutionized the field of physics with his groundbreaking discoveries and theories, is widely regarded as one of the greatest scientists of all time. Born in Germany in 1879, Einstein's contributions to the world of physics have had a lasting impact on our understanding of the universe.One of Einstein's most famous achievements is his theory of relativity, which he first introduced in 1905. This theory, which includes both special relativity and general relativity, revolutionized the way we think about space, time, and gravity. Special relativity showed that the laws of physics are the same for all observers, no matter how they are moving relative to each other. General relativity, on the other hand, describes gravity as the curvature of spacetime caused by mass and energy.In addition to his work on relativity, Einstein also made significant contributions to quantum mechanics, the study of the behavior of particles at the smallest scales. While he was initially skeptical of quantum mechanics, Einstein later made important contributions to the field, particularly in his work on the photoelectric effect, for which he was awarded the Nobel Prize in Physics in 1921.Einstein's work has had a profound influence on many areas of physics, and his ideas continue to shape our understanding of the universe today. His famous equation, E=mc^2, which describes the relationship between mass and energy, is perhaps the most well-known equation in physics. This equation has had far-reaching implications, leading to technological advancements such as nuclear energy and atomic weapons.Beyond his scientific achievements, Einstein was also known for his humanitarian efforts and advocacy for world peace. He was a vocal critic of racism, discrimination, and war, and used his platform as a public figure to advocate for social and political change.In conclusion, Albert Einstein was a brilliant scientist whose work revolutionized the field of physics and changed the way we understand the universe. His theories of relativity and contributions to quantum mechanics have had a lasting impact on our understanding of the world around us. Einstein's legacy as a scientist, thinker, and advocate for peace continues to inspire generations of scientists and thinkers to this day.篇3Albert Einstein was a renowned physicist who is widely regarded as one of the greatest scientists of all time. Born in 1879 in Germany, Einstein's groundbreaking work in theoretical physics revolutionized our understanding of the universe and paved the way for numerous scientific advancements.Einstein's most famous contribution to physics is his theory of relativity, which he developed in 1905. This theory fundamentally changed the way we think about space and time,and has been confirmed by countless experiments over the past century. The theory of relativity has had profound implications for our understanding of the nature of the universe, and has been instrumental in shaping modern cosmology and astrophysics.In addition to his work on relativity, Einstein also made significant contributions to the field of quantum mechanics, which describes the behavior of particles on the smallest scales. His work in this area helped to lay the foundation for the development of modern quantum theory, which has become one of the most successful and widely accepted theories in physics.Einstein's work was not limited to theoretical physics; he also made important contributions to the field of applied physics. In 1921, he was awarded the Nobel Prize in Physics for his discovery of the photoelectric effect, a phenomenon in which electrons are emitted from a material when it is exposed to light. This discovery has had important practical applications in the development of technologies such as solar panels and photovoltaic cells.In addition to his scientific achievements, Einstein was also known for his strong social and political convictions. He was avocal advocate for pacifism and civil rights, and was a staunch opponent of war and violence. Einstein's humanitarian efforts earned him widespread acclaim, and he remains a symbol of peace and tolerance to this day.In conclusion, Albert Einstein was a genius whose contributions to physics have had a lasting impact on our understanding of the universe. His work in theoretical and applied physics has revolutionized the field and paved the way for numerous scientific advancements. Einstein's legacy as a scientist, philosopher, and humanitarian continues to inspire people around the world to this day.。
我的英雄爱因斯坦英语作文
My Hero: EinsteinAlbert Einstein, a name that has transcended the boundaries of time and space, a legend in the annals of science. His contributions to the field of physics are immeasurable, and his theories have revolutionized our understanding of the universe. But to me, Einstein is not just a scientist; he is a hero, a beacon of inspiration, and a testament to the power of human intellect.Born in 1879 in Germany, Einstein defied the norms of his era. He rejected the then-prevailing Newtonian physics and proposed a new theory of relativity that shook the scientific community to its core. His theory of special relativity revolutionized our understanding of time, space, and matter, introducing the concepts of mass-energy equivalence and the famous equation E=mc².But Einstein's journey was not without its challenges. He struggled in school, was considered slow and eccentric by his peers, and even failed to secure a teaching position for several years after graduating. Yet, he persevered, driven by his insatiable curiosity and love for science. His dedication and perseverance are a testament to the factthat success is not solely determined by early achievements or social acceptance, but by the strength of one's convictions and the courage to follow one's dreams.Einstein's legacy does not end with his groundbreaking theories. He was a passionate advocate for peace and social justice, and his letter to President Roosevelt urging the development of the atomic bomb was a testament to his profound moral compass. His belief in the power of reason and science to solve the world's problems is a valuable lesson for us today, in an era where pseudo-science and superstition often thrive.Moreover, Einstein's life story is an inspiration for young minds. He was a man who defied conventions, dared to dream big, and never gave up on his passions. His story teaches us that we should never be afraid to question authority, to challenge the status quo, and to pursue our dreams with determination and courage.In conclusion, Albert Einstein is not just a scientific genius; he is a hero in every sense of the word. His life and work are a powerful reminder of the transformativepower of human intellect and the importance of perseverance,courage, and morality in the pursuit of knowledge and truth. As we look towards the future, let us draw strength from Einstein's legacy and strive to make the world a better place through the power of reason and science.**我的英雄：爱因斯坦**阿尔伯特·爱因斯坦，一个超越时空界限的名字，科学史册上的一位传奇人物。
爱因斯坦的事迹英语作文
爱因斯坦的事迹英语作文Title: The Legacy of Albert Einstein: A Journey Through Brilliance。
Albert Einstein, the iconic physicist whose name is synonymous with genius, left an indelible mark on the world with his groundbreaking discoveries and revolutionary theories. Born in Ulm, Germany, in 1879, Einstein's extraordinary journey from a curious child to a NobelPrize-winning scientist continues to inspire and awe people worldwide. His life and work serve as a testament to the power of imagination, perseverance, and intellectual curiosity.Einstein's early years were marked by an insatiable thirst for knowledge and a keen interest in science and mathematics. Despite facing academic challenges in his youth, he never wavered in his pursuit of understanding the mysteries of the universe. It was during his time as a patent clerk in Switzerland that Einstein first began todevelop his revolutionary ideas about space, time, and energy.In 1905, Einstein published a series of papers that would forever change the course of physics. His theory of relativity, which proposed that space and time are not absolute but rather relative to the observer's frame of reference, challenged long-held beliefs and laid the foundation for modern physics. The famous equation E=mc², which equates mass with energy, is perhaps the most well-known consequence of his theory of relativity and has had far-reaching implications in fields ranging from nuclear physics to cosmology.Einstein's contributions to science were not limited to theoretical physics. He also made significant advancements in the field of quantum mechanics, particularly with his work on the photoelectric effect, for which he was awarded the Nobel Prize in Physics in 1921. His insights into the behavior of particles at the atomic level helped pave the way for the development of technologies such as lasers and semiconductors, which have revolutionized countless aspectsof modern life.Beyond his scientific achievements, Einstein was also a passionate advocate for peace, human rights, and social justice. He spoke out against militarism and nationalism and used his platform to promote dialogue and understanding among nations. His famous quote, "Peace cannot be kept by force; it can only be achieved by understanding," continues to resonate with people around the world today.Despite facing adversity and persecution throughout his life, Einstein remained committed to his principles and never shied away from speaking truth to power. His courage and moral clarity serve as an inspiration to all who strive to make the world a better place.In conclusion, Albert Einstein's life and work represent the epitome of human intellect and imagination. His groundbreaking discoveries and unwavering commitment to truth and justice have left an enduring legacy that continues to shape our understanding of the universe and our place within it. As we reflect on his remarkableachievements, let us remember the words of this extraordinary man and strive to emulate his spirit of curiosity, courage, and compassion in our own lives.。
关于爱因斯坦的英语作文
Albert Einstein,one of the most renowned physicists of all time,was born on March 14,1879,in Ulm,Germany.His groundbreaking work in theoretical physics revolutionized our understanding of the universe and laid the foundation for modern physics.Einsteins early life was marked by a keen interest in mathematics and philosophy.He was not particularly interested in the rote learning style of the schools he attended,but he was deeply curious about the world around him.This curiosity led him to question the nature of reality and the laws that govern it.In1905,Einstein published four papers that would change the course of science.The first paper introduced the concept of the photon and laid the groundwork for quantum theory. The second paper,known as the miracle year paper,introduced the special theory of relativity,which fundamentally altered our understanding of space and time. Einsteins work on the special theory of relativity led to the famous equation Emc²,which shows that energy and mass are interchangeable.This equation has had farreaching implications,not only in physics but also in our understanding of the universes energy sources.In1915,Einstein published his general theory of relativity,which expanded on the special theory and introduced the concept of gravity as a curvature of spacetime.This theory has been confirmed through numerous experiments and observations,including the recent detection of gravitational waves.Einsteins contributions to science did not stop with his theories.He was also a passionate advocate for peace and social justice.He was a vocal critic of the arms race and nuclear weapons,and he used his influence to promote diplomacy and international cooperation.Despite his many accomplishments,Einstein remained humble and curious throughout his life.He once said,The most beautiful thing we can experience is the mysterious.It is the source of all true art and science.His insatiable curiosity and dedication to understanding the universe continue to inspire scientists and thinkers to this day.In conclusion,Albert Einsteins life and work have had a profound impact on our understanding of the world.His theories have shaped the field of physics and continue to influence scientific research.His legacy as a scientist,thinker,and humanitarian endures, reminding us of the power of curiosity and the importance of pursuing knowledge for the betterment of humanity.。
爱因斯坦生平的英语作文
爱因斯坦生平的英语作文Title: The Life and Legacy of Albert Einstein。
Albert Einstein, renowned as one of the greatest physicists of all time, left an indelible mark on the scientific community and the world at large. Born on March 14, 1879, in Ulm, Germany, Einstein displayed an early curiosity and aptitude for mathematics and science. His remarkable intellect and innovative thinking would eventually revolutionize our understanding of the universe. Let us delve into the extraordinary life journey of this extraordinary man.Einstein's early years were marked by intellectual exploration and academic challenges. He struggled within the traditional education system, finding it restrictive and uninspiring. However, his passion for knowledge remained undiminished. In 1905, often referred to as his "miracle year," Einstein published four groundbreaking papers that reshaped the landscape of modern physics. Amongthese was his theory of special relativity, which introduced the famous equation E=mc², demonstrating the equivalence of mass and energy.Following this seminal work, Einstein continued to delve into theoretical physics, probing the fundamental nature of space, time, and gravity. In 1915, he presented his general theory of relativity, providing a new understanding of gravity as the curvature of spacetime. This theory challenged Newtonian physics and laid the groundwork for modern cosmology.Despite his profound contributions to science, Einstein faced personal and professional challenges throughout his life. He experienced difficulties in academia and struggled to find permanent positions, leading him to work in patent offices and universities across Europe. Nevertheless, his relentless pursuit of knowledge and his commitment to pacifism and social justice remained unwavering.Einstein's fame transcended the scientific community, making him a global icon and a symbol of intellectualcuriosity and human potential. His public lectures and writings captivated audiences worldwide, inspiring generations to pursue scientific inquiry and critical thinking.Beyond his scientific achievements, Einstein was a passionate advocate for peace and social justice. He spoke out against war and militarism, emphasizing the importanceof international cooperation and understanding. His advocacy for nuclear disarmament and civil rights earnedhim widespread admiration and respect.In 1921, Einstein was awarded the Nobel Prize inPhysics for his discovery of the photoelectric effect, a phenomenon fundamental to the development of quantum theory. However, he remained humble about his accolades, viewing scientific inquiry as a collective endeavor rather than individual achievement.Einstein's later years were spent grappling with the profound implications of his theories and advocating for a unified field theory that would unify the forces of nature.Despite his efforts, he was unable to achieve this goal, but his contributions paved the way for future generations of physicists to continue the quest for a complete understanding of the universe.Albert Einstein passed away on April 18, 1955, leaving behind a legacy that continues to resonate in the realms of science, philosophy, and culture. His insatiable curiosity, revolutionary ideas, and humanitarian spirit have left an indelible mark on the world, inspiring countlessindividuals to reach for the stars and strive for a better future.In conclusion, Albert Einstein's life story is a testament to the power of intellect, imagination, and perseverance. His contributions to science and society have left an enduring legacy that will continue to inspire and enlighten humanity for generations to come.。
爱因斯坦英语介绍50字
爱因斯坦英语介绍1Albert Einstein was one of the most brilliant scientists in history. Born in 1879, he showed an early interest in science and mathematics. His life was a journey of intellectual exploration and revolutionary discoveries.Einstein's greatest achievement was the formulation of the theory of relativity. This theory completely changed our understanding of space, time, and gravity. The process of proposing this theory was not easy. It required years of intense thought, experimentation, and the courage to challenge conventional wisdom. He persisted in his research despite facing numerous obstacles and skepticism from the scientific community.Einstein's work had a profound impact on the world. It not only advanced theoretical physics but also had practical applications in areas such as satellite navigation and nuclear energy. His ideas continue to inspire scientists to this day.Beyond his scientific contributions, Einstein was also known for his philosophical and humanitarian thoughts. He was a passionate advocate for peace and social justice.In conclusion, Albert Einstein's life and work serve as an inspiration to us all. His dedication to truth, his pursuit of knowledge, and his concern for humanity make him a true icon of the modern age.2Albert Einstein was one of the most brilliant minds in the history of science. Born in 1879, he was not your typical child. His curiosity and passion for understanding the world around him set him apart from the very beginning.Einstein's unique way of thinking often led him to question conventional wisdom. For instance, when he was a young student, he wasn't always the best in traditional academic settings, but his mind was constantly working in ways that others couldn't fathom. This unconventional approach to learning and problem-solving eventually led to his groundbreaking theories of relativity.One of the most fascinating aspects of Einstein was his ability to imagine complex scenarios in his mind. He once said, "Imagination is more important than knowledge." This statement reflects his belief that the power of creativity and thinking outside the box was key to unlocking the mysteries of the universe.His theories not only revolutionized the field of physics but also inspired countless scientists and thinkers after him. His work showed that sometimes, going against the grain and challenging established beliefs can lead to astonishing discoveries.In his personal life, Einstein was known for his simplicity and sense of humor. He had a laid-back attitude and wasn't concerned with materialpossessions or social conventions.Overall, Einstein's charm and wisdom lie in his unwavering pursuit of truth, his unconventional thinking, and his ability to inspire generations to look beyond the surface and explore the unknown.3Albert Einstein was one of the most brilliant scientists in history. His theories have had a profound impact on our understanding of the universe.Einstein's theory of relativity is perhaps his most famous contribution. It completely changed the way we think about space and time. The theory includes the famous equation E=mc², which states that energy and mass are interchangeable. This equation has had significant practical applications, especially in the field of nuclear energy.For instance, in nuclear power plants, the principle of converting a small amount of mass into a large amount of energy based on the equation is utilized to generate electricity. This has provided a powerful and relatively clean source of energy, although it also comes with certain risks and challenges.Einstein's work also influenced our understanding of gravitational forces and the behavior of celestial objects. His theories have helped us make predictions and observations about the universe that were previously unimaginable.In conclusion, Einstein's scientific theories not only expanded ourknowledge but also paved the way for many technological advancements and new discoveries. His genius and dedication to science continue to inspire countless scientists and thinkers around the world.4Albert Einstein is one of the most remarkable figures in the history of science and human thought. His contributions have had an immeasurable impact on our understanding of the universe and the way we view the world.Einstein's theory of relativity revolutionized our perception of space and time. It not only provided a new framework for understanding the behavior of celestial bodies but also had profound implications for modern physics. His ideas challenged conventional wisdom and opened up new avenues of exploration.His work also had a significant influence on technological advancements. For instance, it laid the foundation for the development of nuclear energy and the GPS system that we rely on today. Without Einstein's theories, our technological landscape would be vastly different.Furthermore, Einstein's intellectual curiosity and pursuit of truth inspired countless scientists and thinkers. His insistence on questioning established beliefs and seeking deeper understanding encouraged a spirit of innovation and exploration.In addition to his scientific achievements, Einstein was a passionate advocate for peace and social justice. He used his fame and influence tospeak out against war and injustice, emphasizing the importance of human values and the need for a more equitable world.In conclusion, Albert Einstein's influence extends far beyond the realm of science. His ideas have shaped our modern world and will continue to inspire future generations to strive for knowledge and a better understanding of the universe and humanity.5Albert Einstein is widely regarded as one of the most brilliant scientists of all time. His contributions to the field of physics have not only revolutionized our understanding of the universe but also sparked profound philosophical inquiries.Einstein's theory of relativity, particularly his ideas about time and space, challenged conventional wisdom and forced us to reconsider our fundamental concepts of reality. He proposed that time and space are not absolute but are relative and intertwined, a notion that has profound implications for our perception of the world.For instance, his famous thought experiment about a person traveling at the speed of light and experiencing time dilation demonstrates the complexity and malleability of time. This concept goes beyond the realm of pure science and prompts us to question the nature of existence and our place in the cosmic order.Einstein's work also highlights the importance of imagination andcreativity in the pursuit of scientific knowledge. He was not bound by traditional paradigms but was willing to think outside the box and envision possibilities that others had overlooked.In conclusion, Einstein's scientific achievements not only expanded our knowledge of the physical world but also invited us to reflect on the deeper philosophical questions that underlie our understanding of reality. His legacy continues to inspire and challenge us to think critically and explore the unknown.。
介绍著名人物英语作文
介绍著名人物英语作文Albert Einstein, a name synonymous with genius, was not just a theoretical physicist but a beacon of intellectualcuriosity and relentless pursuit of knowledge. Born on March 14, 1879, in Ulm, in the Kingdom of Württemberg in the German Empire, Einstein's contributions to science have left an indelible mark on human history.Einstein's early life was filled with an insatiable appetite for understanding the world around him. He was fascinated by the works of Euclid and the mechanical workings of a compass, which sparked his lifelong dedication to the pursuit of scientific understanding. Despite facing challenges in his early education, Einstein's perseverance and self-study led him to the Swiss Federal Institute of Technology, where he would later develop the Special Theory of Relativity.His most famous equation, E=mc^2, unveiled the concept that energy and mass are interchangeable and highlighted the enormous amount of energy stored in the atomic nucleus. This equation not only revolutionized the field of physics but also laid the groundwork for the development of nuclear power and weapons.Einstein's impact, however, extended beyond the realm of science. He was a staunch advocate for peace and used his influence to promote humanitarian causes. His letters to political figures and his participation in the League ofNations demonstrate his commitment to a peaceful and just world.In addition to his scientific and philosophical contributions, Einstein was known for his wit and philosophical insights.His quotes on life, education, and the nature of the universe continue to inspire generations to think critically and question the status quo.Einstein's life was not without its struggles. He faced criticism and skepticism from his peers, and his theorieswere initially met with resistance. However, his unwavering belief in his work and his dedication to the pursuit of truth ultimately led to widespread acceptance and admiration.In conclusion, Albert Einstein's life serves as a testamentto the power of curiosity, the importance of perseverance,and the potential for a single individual to change thecourse of history. His work has not only shaped our understanding of the universe but also inspired countless individuals to seek knowledge and question the world around them. As we continue to explore the mysteries of the cosmos, the legacy of Einstein's work will undoubtedly continue to guide and inspire future generations of scientists, thinkers, and dreamers.。
科学家生平事迹英语作文
科学家生平事迹英语作文Title: The Life and Achievements of Albert Einstein.Albert Einstein, a name synonymous with genius and innovation, revolutionized the field of physics with his groundbreaking theories. Born on March 14, 1879, in Ulm, Germany, to a middle-class Jewish family, Einstein exhibited an early proclivity for mathematics and physics. His academic journey was marked by a series of significant achievements that changed the course of science forever.After graduating from high school, Einstein enrolled at the Swiss Federal Institute of Technology in Zurich, where he obtained a degree in physics. His early years were marked by a penchant for有独立思想, which often led him to question established theories. This curiosity and quest for knowledge would later become the driving force behind his remarkable scientific contributions.In 1905, Einstein published four groundbreaking papers,collectively known as his "Annus Mirabilis" (Miraculous Year). Among these were his theories of the photoelectric effect, Brownian motion, special relativity, and the famous equation E=mc2. These theories not only revolutionized physics but also laid the foundation for future scientific explorations.The theory of special relativity, in particular, introduced the concept of time dilation and length contraction, challenging Newton's laws of motion.Einstein's theory proposed that the laws of physics are invariant in all inertial frames of reference and that the speed of light in a vacuum is constant, regardless of the observer's motion. This groundbreaking theory marked a significant departure from classical physics and marked Einstein's emergence as a leading figure in the scientific community.In 1915, Einstein went on to develop his theory of general relativity, which extended the principles of special relativity to include gravity. His theory proposed that mass and energy curve the spacetime fabric, causingobjects to move along geodesics, or the shortest paths, through spacetime. This theory not only explained the phenomenon of gravity but also predicted the existence of gravitational waves and black holes, which were later confirmed through experimental observations.Despite his remarkable achievements, Einstein'spersonal life was fraught with challenges. He struggledwith mental illness and personal losses, yet his dedication to science never wavered. His legacy, however, is not justin his scientific contributions but also in his unwavering commitment to intellectual freedom and social justice.Einstein's impact on science and society is immeasurable. His theories have opened up new frontiers of exploration in physics and other fields, and his legacy continues to inspire generations of scientists and thinkers. His commitment to intellectual freedom and social justice also serves as a beacon for those who seek to make apositive impact in the world.In conclusion, Albert Einstein's life and achievementsare a testament to the power of curiosity and the transformative potential of science. His groundbreaking theories have revolutionized our understanding of the universe, and his legacy continues to inspire and challenge us to push the boundaries of knowledge. His story reminds us that the pursuit of knowledge and the quest for truth are the driving forces that shape our world and define our humanity.。
爱因斯坦 英语作文
爱因斯坦英语作文Albert Einstein was a brilliant physicist who is best known for his theory of relativity. He was born in Germany in 1879 and later moved to the United States, where he became a citizen. Einstein's work revolutionized our understanding of the universe and earned him the Nobel Prize in Physics in 1921.Einstein's theory of relativity, particularly the equation E=mc^2, is perhaps his most famous contribution to science. This equation shows the relationship between energy and mass, and it has had a profound impact on the field of physics. Einstein's work also laid the groundwork for the development of nuclear energy and the atomic bomb.In addition to his scientific achievements, Einstein was also a passionate advocate for peace and civil rights. He was a vocal critic of war and violence, and he spoke out against racism and segregation. Einstein's humanitarian efforts earned him the admiration of people around theworld, and his legacy continues to inspire others to work for positive change.Despite his incredible intellect, Einstein was known for his humility and sense of humor. He had a playful nature and a love of music, and he often used thought experiments and simple analogies to explain complex scientific concepts. Einstein's ability to communicate his ideas in a way that was accessible to the general public helped to make him a beloved figure.In conclusion, Albert Einstein was a remarkable individual whose contributions to science and society have left a lasting impact. His work continues to shape our understanding of the universe, and his advocacy for peace and equality serves as a powerful reminder of the importance of using knowledge for the betterment of humanity.。
英文名作文可用男科学家
英文名作文可用男科学家Title: The Enlightened Mind of a Genius: The Life and Work of Albert Einstein.Albert Einstein, a name synonymous with genius and intelligence, revolutionized the scientific world with his theories and contributions. Born in Germany in 1879, Einstein's life was a testament to the power of the human mind and the boundless possibilities it can unlock. His journey from a curious child to a renowned scientist is an inspiring narrative of perseverance, creativity, and intellectual courage.As a child, Einstein exhibited a keen interest in mathematics and physics. His parents recognized his exceptional talent and encouraged him to pursue his passions. However, his school life was not without challenges. He struggled with traditional learning methods and was often considered a daydreamer. Nevertheless, his determination to understand the mysteries of the universenever wavered.His groundbreaking theory of relativity, published in 1905, marked a seismic shift in the scientific community.It challenged the existing understanding of space, time, and matter, introducing new concepts that were difficult to comprehend. Despite initial resistance, Einstein's theory eventually gained acceptance and is now considered a fundamental part of modern physics.His contributions to the field of quantum theory and his famous equation E=mc² are just two examples of his remarkable achievements. But Einstein's legacy extends beyond his scientific breakthroughs. He was a passionate advocate for peace and social justice, using his fame and influence to speak out against war and inequality.Einstein's life was also marked by personal tragedies, including the loss of his first child and his divorce. However, these challenges never dimmed his spirit or his dedication to scientific exploration. His optimism and belief in the power of human reason were constantsthroughout his life.In conclusion, Albert Einstein's life and work are a testament to the power of the human mind. His legacy is not just in the scientific breakthroughs he made but also inthe example he set as a thinker and humanist. His story reminds us that the potential for greatness lies withineach of us, waiting to be unlocked through curiosity, perseverance, and the courage to挑战 the established order. Einstein's life was a constant quest for understanding, a relentless pursuit of truth, and a powerful reminder of the impact one individual can have on the world.As we look to the future, Einstein's legacy continuesto inspire generations of scientists and thinkers. His work challenges us to question, to explore, and to push the boundaries of our knowledge. His life teaches us about the importance of perseverance, creativity, and the power of human reason. Albert Einstein remains a beacon of inspiration, a reminder that with the right mindset and dedication, we can all make a significant impact on the world.。
名人小故事带翻译
名人小故事带翻译The Story of Albert Einstein: From Patent Clerk to Nobel Prize Winner。
阿尔伯特·爱因斯坦的故事，从专利职员到诺贝尔奖得主。
Albert Einstein is one of the most famous scientists in history, known for his groundbreaking theories onrelativity and the equation E=mc². However, before he became a renowned physicist, Einstein was just a patent clerk in Switzerland.阿尔伯特·爱因斯坦是历史上最著名的科学家之一，以他关于相对论和 E=mc²方程的开创性理论而闻名。
然而，在成为著名物理学家之前，爱因斯坦只是瑞士的一名专利职员。
Einstein was born in Germany in 1879 and showed an early interest in mathematics and science. However, he struggled in school and dropped out at the age of 16. He eventually moved to Switzerland and enrolled in a technicalschool, where he graduated with a degree in physics.爱因斯坦于1879年出生在德国，表现出对数学和科学的早期兴趣。
然而，他在学校里遇到了困难，并在16岁时辍学。
他最终搬到了瑞士，并在一所技术学校注册，获得了物理学学位。
After graduation, Einstein struggled to find a job in academia and instead took a position as a patent clerk in Bern, Switzerland. It was during this time that he developed his theories on relativity and published several papers that would change the course of physics.毕业后，爱因斯坦很难在学术界找到工作，于是他在瑞士伯尔尼担任了一名专利职员。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
a rXiv:h ep-th/97562v11M a y1997A note on the Einstein equation in string theory Sayan Kar ∗Inter University Centre for Astronomy and Astrophysics,Post Bag 4,Ganeshkhind,Pune,411007,INDIA Abstract We show,using purely classical considerations and logical extrapolation of results belonging to point particle theories,that the metric background field in which a string propagates must satisfy an Einstein or an Einstein–like equation.Additionally,there emerge restrictions on the worldsheet curvature,which seems to act as a source for spacetime gravity,even in the absence of other matter fields.String theory,unlike General Relativity(GR),is not a theory of spacetime.It is,ofcourse, not expected to be so,primarily because the notion of a string as a fundamental entity is the alternative to the usual point particle paradigm.Spacetime geometry makes its appearance in string theory in a very different way.Firstly,quantum string theory is believed to include a quantum theory of gravity apart from unifying all the forces of nature.Furthermore,the low energy,effectivefield theory that emerges out of string theory resembles General Relativity(GR)in the Einstein frame (and a Brans–Dicke(BD)type theory in the string frame)[1].This remarkable fact leads us to believe that classical spacetime geometry emerges in the low–energy limit of string theory. The main cause behind it is the assumption that quantum conformal invariance must hold good even if one breaks classical conformal invariance by including the dilaton dependent term in theσmodel action.This enables us to set theβfunction(al)s of theσ–model action to zero.The resultant partial differential equations constitute a set of constraints on the metric,axion(or antisymmetric tensorfield)and dilatonfields which,actually are,couplings at the level of theσmodel.These constraints on the couplings,surprisingly,turn out to be the above–mentioned Einstein–like equations and constitute the low energy effectivefield equations for full string theory.Is there a purely classical way through which one can prove that the conditions on the background metric/matterfields(couplings)in theσ–model action must resemble the Einstein equations?We shall outline in this paper,a possible path through which this can be achieved.It is based on the extrapolation of the well–known relationships between the geodesic deviation equation,the geodesic equation and the Einsteinfield equation to the case of extended objects,or more specifically,strings.The logic proceeds as follows.We recall the following facts from the theory of point particles and General Relativity (GR).(i)The geodesic deviation equation is generically of the form,D2ηiwhere D¨ηi+ ∂i∂jφ ηj=0(2) where a dot denotes a derivative with respect to time t.Thus we get,)=T race(∂i∂jφ)=0⇒∇2φ=0(3) T race(K ijwhich is the vacuum(Laplace)equation for the gravitational potentialφ.In a curved spacetime,the deviation equation remains of a similar form(it is as stated in(1)),but the quantity K i j turns out to be:K i j=RµνρσEµEρnνj nσi(4)where Eµand nµi are the tangent and normals to the geodesic curve.Once again,it is fairly easy to see that:)=0⇒Rµν=0(5)T race(K ijwhere we use nµi nνi=gµν+EµEν.Thus,we arrive at the vacuumfield equation of GR by utilising the same principle.To extend the above logic to the case of string worldsheets we need to know the deviation equation for string worldsheets of Nambu–Goto/Polyakov type.This,fortunately,has been there in the literature for quite some time now[4].It is related,as in the geodesic case,to the second variation of the Nambu–Goto action evaluated at its stationary points and reads :2ηi+ M2 i jηj=0(6) where2denotes the usual D’Alembertian operator on the string world sheet.Theηi are the deviation vector components in the normal directions.More specifically ifδxµis the deformation of the embedding function we haveδxµ=nµiηi+Eµaηa where Eµa are the tangent vectors to the string world sheet with a=σ,τ.We ignore the tangential deformationηa, because,by reparametrisation invariance we can say that this does not cause any changesin the worldsheet geometry.The quantity(M2)i(which replaces the K i j mentioned earlier)jis given as:M2 i j=K abi K abj+RµνρσEµa nνi Eρa nσj(7) where K abi denotes the extrinsic curvature of the embedded string world–sheet in the direction of the i th normal nµi.The Eµa are the tangent vectors to the string world sheetby definition is dependent on the choice of the normal with a=σ,τ.Note that the(M2)ijframe.However,when we take a trace this ambiguity goes away and we get a quantity which is independent of the choice of normals.(The same is true for the case of geodesic curves).It should also be stated that we have implicitly assumed in our deviation equation the existence of those extremal worldsheets for which the normal fundamental form(µa ij=gµνnµi Eαa Dαnνj) vanishes.This is not too restrictive as can be seen by inspectingµa ij for the multitude of string configurations available in various curved background geometries.Therefore,on extrapolating the condition for the point particle case to strings,we get:)=T race[(M2)i j]=−2R+RµνEµa Eνa=0(8) T race(K ijwhere we have used the traced Gauss–Codazzi integrability condition and the extremality condition K i=0in order to arrive at the above expression after taking the trace with respect to the normal indices.The above criterion has been obtained in a different way recently in[7].There,once again,one utilises the requirement of one–loopfiniteness of Nambu–Goto string theory.The authors in[7]propose this as a consistent condition for one–loopfiniteness,by writing the above equation as an equation on the worldsheet.We shall show that the condition can be split into two separate conditions–one on the worldsheet and one on spacetime geometry in a very simple way.It should be mentioned that the quantity T race(K i j)appears in the generalised Ray-chaudhuri equation for worldsheet congruences of Nambu–Goto strings[5]which is given as :12F+are the expansions along theσandτdirections on the worldsheet.This Ffact is true for the Raychaudhuri equation for geodesic congruences in Newtonian as well as Riemannian spacetimes.Also note that in both the deviation equation for extremal worldsheets and the gener-alised Raychaudhuri equation there appears contributions from the worldsheet geometry–the K i ab K ab j term in the deviation equation and the−2R term in the generalised Raychaudhuri equation.Thus even in the absence of spacetime gravity,worldsheet extrinsic curvature can cause them to deviate and worldsheet intrinsic curvature can lead to worldsheet focus-ing effects.This is,however,expected to happen for extended objects and should not be considered as too surprising!What is the corresponding vacuum Einstein equation?Notice that thefirst term in the above expression(i.e.2R)in T race(K i j)is an explicit function ofσ,τwhile the second term is a mixture of terms which are explicit functions of xµ(Rµν)as well as terms which are explicit functions ofσ,τ(the tangent vectors Eµa).The only way in which we can have T race(K i j)=0is to equate each term to the same quantity.Therefore,specifically,we can have,Rµν=Λ(x)gµν(10)2R=2Λ(x(σ,τ))(11) Thefirst of these equations is,in general,in spacetime.One can also evaluate it on the worldsheet by using the embedding function xµ(σ,τ).The second equation,on the other hand,is exclusively on the worldsheet itself and one cannot convert it into a spacetime equation because the embedding functions cannot be inverted.To satisfy a conservation law, one needsΛto be a constant.Thus,vacuum spacetimes in which string worldsheets can propagate are essentially Einstein spaces[6].Note that this also includes spacetimes with Rµν=0(theΛ=0case).Worldsheet curvature seems to act as a cosmological constant.Thus the existence of string worldsheets with a nonzero worldsheet curvature essentially imply the existence of afinite cosmological constant.Equating the T race(K i j)to zero in Newtonian theory and in GR amounts to consider-ing vacuum spacetimes.However,vacuum,in the presence of strings,as opposed to point particles naturally contains worldsheet curvature which can act as a source for spacetime gravity.This is an important difference which one must remember while dealing with ex-tended objects.Therefore,the vacuum equation in the presence of strings is not just the equation Rµν=0which appears as a special case when we consider onlyflat worldsheets. For p–branes the same rule applies–the only difference is that2R is now replaced by p+1R –the Ricci scalar for the p–brane world–surface.We now illustrate the above facts with an example.The simplest possiblity is to look at spacetimes which satisfy Rµν=0.Correspondingly,one would require2R=0.Minkowski spacetime is a trivial example.For instance if we consider Minkowski spacetime in spherical polar coordinates,the closed string solution t=τ,r=r0,θ=π(K1+K2)=0(where K1,2are the principal curvatures)clearly implies2R=K1K2=−K21 2be a non–positive quantity.Therefore,the background spacetime could be a geometry with a negative cosmological constant with its value being equal to the negative of the square of one of the principal curvatures of the embedded worldsheet.Thus,the black hole spacetime of Banados,Teitelboim and Zanelli[8]can be an admissible background geometry.However, one has to make sure that constant negative curvature worldsheets exist in such backgrounds.More generally,it is possible that one equates the Rµνto an object related to the energy–momentum tensor for an extra,auxiliaryfieldχ.In a somewhat general setting one may write the resultant Einstein equation as:Gµν=Λ(χ)Tχµν(12)and the corresponding expression for2R as:2R=Λ(χ) N−4−gTµν=1where we have chosen to work in the conformal gauge.Theδfunction in the above expression ensures that we are evaluating the Tµνon the worldsheet.Note also that in the above expression there is no assumption about the ex-tremality(K i=0)of the worldsheet.The test–string action when added to the gravity+ matter action is assumed not to effect the structure of the background geometry..We now impose the conservation law Tµν;ν=0and see if we get back the string equation of motion. The steps are outlined below1.Evaluating the covariant divergence of the Tµνamounts to the calculation of the covariant divergence of the quantity within brackets in the integrand.We therefore have:∇µ(eµτeντ−eµσeνσ)=0(15) where we have denoted eµτ=˙xµand eµσ=x′µ.On explicitly writing out the action of the covariant derivative,we obtain,eµτ∇µeντ+eντ∇µeµτ−eµσ∇µeνσ−eνσ∇µeµσ=0(16) We now contract this equationfirst with eντ.This yields,on using the fact that eµa eµb=Ω2(ξ)ηab and eνa∇µeνa=0(a not summed here),Ω2∇µeµτ=0(17) Similarly,on contracting with eνσwe obtain,Ω2∇µeµσ=0(18) Substituting both these expressions into the covariant derivative of the quantity in brack-ets in the integrand of the spacetime energy–momentum tensor we obtain,¨xµ−xµ′′+Γµρσ(˙xρ˙xσ−xρ′xσ′)=0(19)This is the string equation of motion in a generic curved spacetime!Therefore,from the covariant conservation law of the spacetime energy–momentum of the test–string we have arrived at the string equation of motion.Thus,by a simple extrapolation of known facts from point particle theories we have been able to derive the following results:•The compatibility conditions on the metric tensor which appears as a coupling in theσmodel action turn out to be the vacuum Einstein equation/the condition for a spacetime to be an Einstein spacetime or the vacuum Brans–Dickefield equation.This conclusion is based on the extrapolation of the relation between the geodesic deviation equation and the vacuum Einstein equation to the case of string world–sheets.•The conservation law for the spacetime energy momentum tensor of a test–string leads to the string equation of motion in a generic curved background.Thus,the field equations contain the equation for test–strings(similar to the point particle case) through the conservation law.But afield equation governing the dynamics of the background gravitationalfield can only be the Einstein equations/Brans–Dickefield equations if we demand an automatic satisfaction of the conservation law through the Bianchi identity!Note that our conclusion is dependent on the assumption that the equation for test–strings be contained in thefield equation,which is an extrapolation of the corresponding fact in the point particle case.We believe that these results can be generalised to otherσmodels as well,which include the axion,dilatonfields or possess world–sheet/spacetime supersymmetry.The crucial feature about the above‘derivation’is the fact that we have exclusively used results of classical physics.Therefore,if we have strings as opposed to point particles the background spacetime geometry should essentially obey the same Einstein/Brans–Dicke typefield equations with the curvature of the worldsheet in some sense acting as the source for spacetime gravity even in the absence of other sources of matter stress energy.The author thanks S.Bose,S.Das,S.K.Rama,K.Ray,A.Sen,and Y.Shtanov for com-ments and discussions.Financial support from the Inter–University Centre for Astronomy and Astrophysics is also gratefully acknowledged.REFERENCES[1]M.S.Green,J.H.Schwarz and E.Witten,Superstring Theory,Cambridge UniversityPress,Cambridge,U.K.,1987[2]R.D’Inverno,Introducing Einstein’s Relativity,Oxford University Press,Oxford,U.K.1992,pg134[3]A.Einstein and J.Grommer,Sitz.Preuss.Acad.Wiss.1(1927);L.Infeld and A.Schild,Rev.Mod.Phys.21,408(1949);M.Carmeli,Classical Fields:General Relativity and Gauge Theory,Wiley–Interscience(1982)[4]J.Guven,Phys.Rev.D48,5562(1993);rsen and V.P.Frolov,Nucl.Phys.B414,129(1994);R.Capovilla and J.Guven,Phys.Rev.D51,6736(1995)[5]R.Capovilla and J.Guven,Phys.Rev.D52,1071(1995);S.Kar,Phys.Rev.D52,2036(1995),Phys.Rev.D53,2071(1996);Phys.Rev.D54,6408(1996);Phys.Rev.D55(1997)(To appear)[6]L.F.Eisenhart,Riemannian Geometry,Princeton University Press,(1960)[7]K.S.Viswanathan and R.Parthasarathy,Phys.Rev.D55,3800(1997)[8]M.Banados,C.Teitelboim and J.Zanelli,Phys.Rev.Letts.69,1849(1992)。