They do everything that can oscillate, accelerate, disturb, distill, combine, weigh or become gas; In this process, they put forward many general laws. These laws are important and arrogant. To this day, we often write them in capitals: electromagnetic field theory of light, Li Xite's reciprocity law, Charles gas law, volume binding law, zero law, atomic valence concept, mass action law and so on. The whole world tinkled with the sound of the machines and instruments they invented. Many smart people think that scientists have nothing to do.
1875, a young man named Max Planck in Kiel, Germany hesitated, not knowing whether to study mathematics or physics in this life. People sincerely advised him not to choose physics because the main problems in physics have been solved. They told him clearly that the next century will be a century of consolidation and improvement, not a century of revolution. Planck wouldn't listen. He delved into theoretical physics and devoted himself to the study of entropy, the core problem of thermodynamics. For an ambitious young man, it seems promising to study this problem. 189 1 year, he made achievements, but he was surprised to find that this important work on entropy had been done. He is a lonely scholar at Yale University named J Willard Gibbs.
Gibbs is an outstanding figure, but most people may not have heard of him. He behaves well and seldom shows his face. Apart from studying in Europe for three years, he has lived almost all his life in a three-block area: his home on one side and Yale University campus in New Haven, Connecticut on the other. In his first ten years at Yale University, he didn't even bother to get paid. He has another income. ) From 187 1, he became a professor in this university until 1903. During this period, on average, only one student took his class every semester. His writing is obscure, and he often uses symbols invented by himself, which many people think is just a gobbledygook. However, in the depths of those mysterious formulas, the most wise and profound insights are hidden.
During the period of 1875- 1878, Gibbs wrote a series of papers and compiled On the Balance of Multiphase Substances. This book brilliantly expounds almost all thermodynamic principles-in William H. Cooper's words, including "gas, mixture, plane, solid, phase shift" ... chemical reaction, electrochemical cell, precipitation and infiltration ". In the final analysis, Gibbs wants to show that thermodynamics is not only applicable to heat and energy in such a huge and noisy range as steam engines, but also exists at the atomic level of chemical reactions, with great influence. Gibbs' "equilibrium" has always been called "thermodynamic principle", but for unpredictable reasons, Gibbs is willing to publish these epoch-making views in the Journal of Connecticut College of Arts and Sciences, which is unknown even in Connecticut. That's why Planck didn't hear his name until very late.
Planck was not discouraged-alas, maybe a little timid, and began to turn his attention to other problems. We'll talk about this later. Let's make a slight (appropriate) change of direction and go to Cleveland, Ohio, an institution then called Case College of Applied Sciences. In 1980s, there was a middle-aged physicist named albert michelson. With the help of his friend Edward Morey, he conducted a series of experiments. Those experiments have produced interesting and surprising results, which will have a great influence on many things in the future.
What Michelson and Morey did-actually unintentionally-destroyed people's long-standing belief in something called the optical ether. It is a stable, invisible, weightless, frictionless and, unfortunately, completely fictional medium. People think that this medium fills the whole universe. Descartes put forward the hypothesis of ether and Newton accepted it. After that, almost everyone revered it and occupied an absolute central position in physics in the19th century, which was used to explain why light can spread in empty space. It is especially necessary at the beginning of19th century, because both light and electromagnetism are regarded as waves, that is to say, some kind of vibration. Vibration must occur in something, so it needs an ether, and people have long thought that there is an ether. Until 1909, the great British physicist J·J· Thomson still insisted: "Ether is not the imagination of any thoughtful philosopher, it is as indispensable to us as the air we breathe." After he said this for more than four years, it is indisputable that the ether does not exist. In a word, people really can't live without ether.
If you need to explain that America is a land full of opportunities in the19th century, it is hard to find another good example like albert michelson. He was born in 1852 in a poor Jewish merchant family in the border area between Germany and Poland. When he was a child, he came to the United States with his family and grew up in a miner's village in the gold rush area of California. His father is in the textile business there. His family was too poor to go to college, so he came to Washington and wandered around the main entrance of the White House, hoping to meet the president every day when Ulysses S. Grant went out for a walk. (It was obviously a relatively simple era. During this walk, Michelson won the president's heart, and Grant promised to send him to the United States Naval Academy for free. Michelson studied physics there.
10 years later, Michelson, a professor at Case College in Cleveland, became interested in measuring something called ether drift-a headwind caused by moving objects passing through space. One prediction of Newtonian physics is that, in the observer's view, the speed of light passing through the ether is different, depending on whether the observer moves towards or against the light source. But no one can think of a way to measure it. It suddenly occurred to Michelson that the earth moved in the direction of the sun for half a year and in the opposite direction for half a year. He believes that as long as we carefully measure the relative seasons and compare the speed of light between them, we can find the answer.
Michelson persuaded Alexander Graham Bell, the telephone inventor who had just made a fortune, to provide funds to make a smart and sensitive instrument called Michelson's own interferometer, which was used to measure the speed of light very accurately. Then, with the help of the kind and mysterious Morey, Michelson made a careful measurement for several years. This is a very meticulous and laborious job. Michelson's spirit suddenly broke down and his work had to be interrupted for some time. However, by 1887, they had a result. And this result is completely beyond the expectation of these two scientists.
Kip S Thorne, an astrophysicist at California Institute of Technology, wrote: "It turns out that the speed of light is the same in all directions and seasons." This is the first sign in 200 years-in fact, it happens to be 200 years-that Newton's laws may not apply at any time and anywhere. In the words of William H. Cropper, the Michelson-Morey result is "probably the most negative result in the history of physics". Because of this, Michelson won the Nobel Prize in Physics-thus becoming the first American to win this honor-but that will be 20 years later. At the same time, the Michelson-Morey experiment, like a musty smell, floated unpleasantly in the minds of scientists.
It is worth noting that, despite his discovery, when the 20th century came, Michelson, like others, thought that scientific work was coming to an end-in the words of an author in Nature magazine, "just adding a few towers and spires and carving a few reliefs on the roof."
Of course, in fact, the world is about to enter a scientific century. By then, everyone will know a little, and no one will know everything. Scientists are about to find themselves floating in the Wang Yang sea of particles and antiparticles. Things exist and disappear instantly, making nanosecond time seem very slow and ordinary, and everything is so strange. Science is changing from macroscopic physics to microscopic physics. The former, objects can be seen, touched and measured; The latter, things happened suddenly, incredibly fast, completely beyond imagination. We are about to enter the quantum age, and the first person to open its door is Max Planck, who has been unlucky so far.
1900, Planck was 42 years old and was already a theoretical physicist at the University of Berlin. He revealed a new "quantum theory" that energy is not continuous like running water, but something transmitted in the form of packets, which he called quantum. This is indeed a novel concept and a good one. In a short time, it can provide an explanation for the mystery of Michelson-Morey experiment, because it shows that light is not necessarily a wave. In the long run, it will lay the foundation for the whole modern physics. Anyway, this is the first sign that the world is about to change.
However, epoch-making events-the dawn of a new era-will not happen until 1905. At that time, the German physics magazine Yearbook of Physics published a series of papers by a young Swiss employee. He doesn't have a university position or his own laboratory. He usually only runs in the small library of Bern National Patent Office. He is a three-level technical examiner in the patent office. Not long ago, he applied to be promoted to inspector II, but was rejected. )
His name is Albert Einstein. In that important year, he contributed five papers to the Yearbook of Physics. In the words of C.P. Si Nuo, three of them are "the greatest works in the history of physics"-one uses Planck's quantum theory to test the photoelectric effect, one discusses the situation of suspended small particles (now called Brownian motion), and the other summarizes the special theory of relativity.
The first article explained the nature of light (and made many things possible, including television), which won the Nobel Prize for the author.
The second article provides evidence that atoms do exist-surprisingly, this fact has been controversial in the past.
The third article completely changed the world.
Einstein was born in Ulm, southern Germany, on 1879, but grew up in Munich. His early life hardly shows that he will become a big shot in the future. As we all know, he didn't learn to speak until he was three years old. In the 1990s, his father's electrical business went bankrupt and his family moved to Milan, but Albert, who was already in his teens, went to Switzerland to continue his studies-although he failed in the college entrance examination at first. From 65438 to 0896, he gave up his German nationality to avoid being drafted into the army and entered the Swiss Federal Institute of Technology in Zurich for a four-year course aimed at training middle school teachers. He is a clever but not excellent student.
1900, he graduated from school, and within a few months, he began to contribute to the Physical Yearbook. His first paper, on the physics of fluids in straws, was published in the same issue as Planck's quantum theory. From 1902 to 1904, he wrote a series of papers on statistical mechanics. It was found that the prolific J Willard Gibbs had quietly published the same book in Connecticut in 190 1 year: the basic principles of statistical mechanics.
Albert once fell in love with a classmate, a Hungarian girl named Milla Wa Marich. 190 1 year, they gave birth to a son and a daughter and were not married. They were cautious and gave their children to others. Einstein had never seen his children. Two years later, he married Marich. During this period, Einstein accepted a position in the Swiss Patent Office and stayed there for seven years. He likes this job very much: it is challenging and can keep his brain busy without distracting him from physics. It was against this background that he founded the special theory of relativity in 1905.
On electrodynamics of moving objects is one of the best scientific papers ever published, both in expression and content. It has no footnotes, no quotations, almost no mathematics, and it doesn't mention any works that have influenced or preceded the paper, just thanking one person for his help. He is a colleague of the Patent Office, and his name is Michelle Besso. C.P. Si Nuo wrote that Einstein seemed to "think and draw conclusions by himself without listening to other people's opinions". To a large extent, that's it. "
His famous equation E=mc2 did not appear in this paper, but appeared in a short supplement a few months later. You can recall what you learned at school. In the equation, e stands for energy, m stands for mass, and c2 stands for the square of the speed of light.
In the simplest terms, this equation means that mass and energy are equivalent. They are two forms of the same thing: energy is the released mass; Mass is energy waiting to be released. Since c2 (the square of the speed of light) is a huge number, this equation means that every object contains a huge amount of energy-really a huge amount of energy.
You may feel that you are not strong, but if you are an ordinary adult, your humble body contains no less than 7× 10 18 joules of potential-the power of explosion is equal to 30 hydrogen bombs, if you know how to release them and are really willing to do so. There is such energy in every object. We are just not good at releasing it. If we were smarter, even the uranium bomb-the most powerful guy we made-would release less energy than it could 1%.
Among them, Einstein's theory explains how radiation occurs: how a piece of uranium continuously releases intense radiation energy without melting like ice. (As long as mass is converted into energy very efficiently, it is possible: E=mc2. This theory explains why stars can burn for billions of years without running out of fuel. (same as above. ) Einstein broadened the horizons of geologists and astronomers for billions of years with a simple formula. In particular, the theory shows that the speed of light is constant and the fastest, and nothing can surpass it. Therefore, this makes us suddenly understand the core of the nature of the universe. Moreover, the theory also solves the problem of optical ether, indicating that it does not exist. Einstein's universe doesn't need ether.
Physicists generally don't pay much attention to what the staff of the Swiss Patent Office published, so Einstein's paper didn't attract much attention despite providing rich and useful information. Because he had just solved some of the most difficult mysteries in the universe, Einstein applied for the position of university lecturer, but was rejected. Then he applied for the position of a middle school teacher and was rejected. So, he resumed the work of the third-level examiner-but of course he didn't stop thinking. He is far from success.
Once, the poet paolo valeri asked Einstein if he had a notebook with him to record his thoughts. Einstein gave him a slightly surprised look. "Oh, that's unnecessary," he answered. "I seldom bring a notebook." I don't need to point out that it would be very beneficial if he really brought a notebook. Einstein's next idea is the greatest idea of all. Motz and Weaver said in their original history of atomic science that it is indeed the greatest idea. "As the originality of the brain," they wrote, "this is undoubtedly the highest intellectual achievement of mankind." This evaluation is of course very high.
1907, anyway, sometimes the book says that when a worker fell from the roof, Einstein began to think about gravity. God, like many touching stories, the truth of this story seems to be questioned. According to Einstein himself, when he thinks about gravity, he just sits in a chair.
In fact, Einstein thought it was more like starting to find the answer to the gravity problem. From the beginning, he clearly realized that the special theory of relativity lacked one thing, and that was gravity. The reason why special relativity is "narrow" is that it studies things that move completely without obstacles. But what if a moving thing-especially light-meets an obstacle like gravity? He spent most of the next 10 years thinking about this problem, and finally published a paper entitled Cosmological Thinking on General Relativity at the beginning of 19 17. Of course, 1905' s special theory of relativity is a profound and important achievement. However, as C.P. Si Nuo once pointed out, if Einstein hadn't thought of it, others would have thought of it, maybe within five years. This is something waiting to happen. However, general relativity is quite another matter. "Without it," Si Nuo wrote in 1979, "we might still be waiting for that theory today."
Einstein often had a pipe in his hand, so he was affable, unobtrusive and had messy hair. He is really an extraordinary man. Such a person can't be unknown forever. 19 19, when the war ended, the world suddenly found him. Almost at the same time, his theory of relativity is famous for being difficult for ordinary people to understand. The New York Times decided to write a report-for reasons that will never be understood-and sent a golf reporter named Henry Crouch to cover it. As a result, as David Boddenis pointed out in his excellent book E=mc2, the problem has not been solved at all.
Crouch was at a loss in this interview. He almost got everything wrong. There are many unforgettable mistakes in his report. One of them is that Einstein found a courageous publisher who dared to publish a book that only 12 people in the world could understand. Of course, there is no such book, no such publishing house, and no such narrow academic circle, but this view has been deeply rooted in the hearts of the people. Not long after, in people's imagination, there are fewer people who understand the theory of relativity-it should be pointed out that the scientific community has not clarified this myth.
A reporter asked arthur eddington, a British astronomer, whether he was really one of the only three people in the world who could understand Einstein's theory of relativity. Eddington thought for a moment and then replied, "I wonder who the third person is." In fact, the problem of relativity is not that it involves many differential equations, Lorentz transformations and other complicated mathematics (although it does involve-even Einstein needs help in some aspects), but that it cannot be fully understood by intuition.
In essence, the content of relativity is: space and time are not absolute, but relative to the observer and the observed; The faster a person moves, the more obvious this effect will be. We can never accelerate ourselves to the speed of light; Compared with bystanders, the harder we work (so the faster we walk), the more distorted our appearance will be.
Almost at the same time, people engaged in popular science work also want to try to make the masses understand these concepts. Mathematician and philosopher Russell's theory of relativity ABC is a successful attempt-at least in business. Russell used a metaphor that has been used many times in this book. He asked readers to imagine a 90-meter-long train traveling at 60% of the speed of light. For those who stand on the platform and watch it pass by, the train looks only 70 meters long, and everything on the train is also reduced. If we can hear people talking in the car, their voices will sound vague and slow, just like playing a record too slowly, and their movements will look clumsy. Even the clock in the car seems to move at only four-fifths of the normal speed.
However-that's the problem-people on the bus don't feel deformed. In their view, everything in the car seems to be normal. However, on the platform, we are strangely smaller and slower. You see, all this is related to your relative position with the moving object.
In fact, every time you move, you will have this effect. When you fly over the United States, you will get out of the plane in about one billionth of a second, which is younger than anyone who leaves the plane behind you. Even when you walk from one end of the room to the other, the time and space you experience will change slightly. According to the calculation, a baseball thrown at the speed of160km/h will get 0.000000000002g when it reaches the home plate. Therefore, the role of relativity is concrete and measurable. The problem is that this change is too small for us to notice. However, for other things in the universe-light, gravity, the universe itself-these are important events.
So, if the concept of relativity seems a bit strange, it is only because we have never experienced this kind of interaction in our daily life. However, we have to turn to Bonidans, and all of us often encounter other kinds of relativity-such as sound. If you are in the park and someone is playing bad music, you know, if you go further, the music seems lighter. Of course, that's not because music is really light, but because your orientation of music has changed. For things that are small or slow-moving, so it is impossible to have the same experience-such as snails-it seems that one speaker can play two volumes of music to two listeners at the same time, which may be unbelievable.
Among the many concepts of general relativity, the most challenging and intuitive one lies in the concept that time is a part of space. We instinctively believe that time is eternal, absolute and unchangeable, and believe that nothing can interfere with its firm pace. In fact, Einstein believed that time can be changed, and it is constantly changing. Time and even shape. The combination of one time and three spaces-in Stephen Hawking's words, "inextricably intertwined"-mysteriously formed a "time and space".
Usually, time and space are explained in this way: imagine a flat and elastic thing-such as a carpet or a straight rubber mat-with a heavy and round object, such as an iron ball. The weight of the iron ball makes the cushion below slightly stretch and sink. This is roughly similar to the effect of a giant like the sun (iron ball) on time and space (bottom pad): the iron ball makes the bottom pad stretch, bend and tilt. Now, if you let a smaller ball roll on the mat, it will try to move in a straight line, just as Newton's law of motion requires. But when it is close to the big ball and the concave part of the bottom pad, it rolls to the lower part and is inevitably sucked away by the big ball. This is gravity-the product of space-time bending.
Any object with mass can make a small pit on the bottom cushion of the universe. Therefore, as Dennis Overby said, the universe is a "final settlement pad". From this perspective, gravity is not so much a result-in the words of physicist Misio Kaku, "it is not a force, but a by-product of the bending of time and space." Kaku went on to say: "In a sense, gravity does not exist; What makes planets and stars move is the deformation of space and time. "
Of course, the metaphor of the bottom cushion can only help us understand this degree, because it does not include the role of time. Having said that, in fact, our brains can only imagine this. It is almost unimaginable that space and time are woven into a space-time at the ratio of 3: 1 like a thread woven into a grid mat. Anyway, I think we will all agree that this is really a great insight for a young man staring out of the window of the patent office in the Swiss capital.
Einstein's general theory of relativity put forward many opinions. Among them, he thinks that the heart of the universe is always expanding or contracting. However, Einstein was not a cosmologist. He accepted the popular view that the universe is fixed and eternal. More or less instinctively, he added what he called the cosmological constant to the equation. He regarded it as a mathematical pause key, which counteracted the effect of gravity at will. Science history books always forgive Einstein's mistakes, but this is actually a terrible thing in science. He called it "the biggest mistake I made in my life".
Coincidentally, just as Einstein added a constant to his theory, an astronomer at the Lowell Observatory in Arizona recorded the readings on the spectra of distant stars and found that these stars seemed to be moving away from us. This astronomer has a beautiful name from the Milky Way: Vesta Slipher (he is actually from Indiana). It turns out that the universe is not static. Slipher found that these stars clearly showed signs of Doppler shift-the same mechanism as the coherent and unique "Cha-Whoosh" sound made by cars passing by the track. This phenomenon also applies to light; As far as galaxies are concerned, it is called red shift (because light far away from us moves to the red end of the spectrum, while light near us moves to the blue end).
Slipher was the first person to notice this effect of light and realized that it is very important to understand the motion of the universe in the future. Unfortunately, no one noticed him. You will remember that percival Lowell studied canals on Mars here, so Lowell Observatory is a unique place. In the first 10 year of the 20th century, it became an outpost of astronomical research in any sense. Slipher doesn't know Einstein's theory of relativity, and the world doesn't know Slipher, so his discovery has no influence.
On the contrary, the honor belongs to a very conceited big man. His name is Edwin Harper. Hubble was born in 1889 in a Missouri town on the edge of Ozark Plateau, and he was 10 years younger than Einstein. He grew up in Wheaton, Illinois, a Chicago suburb. His father is a successful insurance company manager, so life at home is always comfortable. Edwin was also born with a good figure. He is a powerful and talented athlete, charming, fashionable and handsome-in the words of William H. Cropper, "handsome to an inappropriate degree"; In the words of another admirer, "beautiful as adonis". In his own words, when he saved people from drowning, he often did something courageous; Lead frightened people across the French battlefield and take them to safety; In the exhibition match, the world champion boxer was knocked to the ground at once, which made them very embarrassed. All this is too good to be true, but it is true. Despite his outstanding talent, Hubble is also a stubborn liar.
This is unusual, because Hubble's life has been full of real strangeness since childhood, and sometimes it is incredible to be outstanding. Only in a middle school track and field sports meeting in 1906, he won the champion of pole vault, shot put, discus, hammer throw, standing high jump and run-up high jump. He was a member of the winning team in the relay race-that is to say, he won seven firsts in a sports meeting, and he won the third place in the long jump. In the same year, he set the Illinois high jump record.
As a scholar, he is also excellent, and he was admitted to the University of Chicago as easy as blowing off dust to study physics and astronomy (coincidentally, the head of the department is albert michelson). There, he was selected as one of the first Rhodes scholarship winners in Oxford University. Three years' life in England obviously went to his head. 19 13 When he returned to Wheaton, he was wearing a long cloak and holding a pipe. He speaks in a strange tone, and he talks endlessly-not like an Englishman, but a little like an Englishman-and he keeps this tone all his life. He later claimed that he worked as a lawyer in Kentucky for most of the 1920s, but in fact he worked as a middle school teacher and basketball coach in New Albany, Indiana, and later got a doctorate and spent a short time in the army. He arrived in France a week before signing the armistice agreement, and almost certainly never heard angry gunshots. )
19 19 years, he is 30 years old. He moved to California and got a job at the Mount Wilson Observatory near Los Angeles. To our surprise, he soon became the most outstanding astronomer in the 20th century.
It is worthwhile to pause for a moment and consider how little people knew about the universe at that time. Astronomers today believe that there may be140 billion galaxies in the visible universe. This is a huge number, much bigger than what you think after hearing this. If a galaxy is compared to a frozen bean, these beans can fill an auditorium-for example, Old Boston Garden or Royal Albert Hall. (An astrophysicist named Bruce Gregory actually calculated it. ) 19 19, Hubble for the first time