Reading, scientific research and life path

"Reading, scientific research and Life path"

--Lecture notes of "Spark Forum" at Tsinghua University (2013/4/25)

I am a Tsinghua alumni, graduated from 1970 years. After graduation years, can have the opportunity to return to his alma mater, in the "Spark forum" and is generally the second-generation gap between primary and secondary schools, girls exchange their own lifetime reading, scientific research and life work lessons, experience and experience, the mood is both excited and disturbed. Like a vintage old man, is open deep buried years of old jar, regardless of the brewing is the mellow wine, the bitter bitterness of the bitterness, or the mistake into the vinegar, it after all the way the ups and downs of acid sweet, carrying heavy years of precipitation. It might be useful to Yimeimei, right?

The topic is Lin XX classmate out of, be considered a proposition composition to strike.

1. Reading

According to Chinese tradition, all of you here are scholars. There is no doubt about the importance of reading. We do not talk about utilitarian views, such as "The book has its own gold house, the book has its own Yanruyu" and the like. Only from the point of view of scholarship, reading is the most important way to accept the cultural heritage of previous generations. Everyone is reading, but the effect may be different. " how to read books " is a science in itself.

What books 1.1 read

1979 Nobel Prize winner glashow Physics -related knowledge In addition to music, East Asian History, law, literature, and even welding. Visiting his correspondent was puzzled and asked: "Is it also helpful to learn so many other subjects for the physics research?" He replied: "I think there are, often many of the answers to physics questions are not within the scope of physics, and a wide range of learning can provide open ideas, such as more read novels, the time to visit the park, will be beneficial. This can improve the imagination. It is just as important as understanding and memory. "The Sea is hundred rivers, the square can become its big." A great weakness of many Chinese scholars is that they can only work in a very small direction for a lifetime.

Special want to emphasize is: Science and engineering students to learn Chinese, arts student of course also must master the necessary natural science knowledge. Some people say: "The arts and Sciences are interlinked", I think there is some truth. The logic of writing an article is consistent with mathematical reasoning in principle. Shing said: "In learning maths, but also not neglected language." The training of Chinese is the first step to become a true scholar. T.D. Lee has an inscription: "Scientific Humanities one shoulder to pick." So science and engineering students, in addition to professional knowledge, should also take time to read a little literature, philosophy, and social science books.

1.2 How to read

What I want to say is a professional book . Personally think can be divided into two categories: one is a basic textbook, this kind of books to be intensive reading. For example, I have never studied graph theory before, and for a while I studied graph theory, and I chose an introductory book "R. J. Wilson, Introduction tograph theory". My general practice is: Choose a book that is easy to read and more classic, read it carefully as a textbook, and every proof is carefully looked at, each exercise is done. Hua said reading from the thin read to thick, and then from thick read to thin. From thin to thick is the process of intensive reading , to understand each concept, including taking notes, doing exercises, this is the first step. After mastering these contents, we should synthesize and refine and find out the essence that really need to be mastered. In the future, it is possible to remember what you really can, but you can do it comprehend by analogy.

I had a friend who joined me from Tsinghua University to graduate School of Science. After decades of meeting, he said: "We have learned a lot of math, in fact, the last thing to remember is some framework." "I think he talked about the idea that these are not many frameworks that guide us to the right thinking. This is probably the so-called "by the return of the Bo, to about the Yu Bo" principle. A People art theater multi-body, more than one course will be more than a skill.

The other is a reference book, including a large number of references (except for a few exceptions to be read). These things should be rough time, to master the ideas and methods that you think are useful or enlightening. This is a kind of ability training, middle school students, even college students are difficult to do this. But as a graduate student, especially in knowledge explosion today, we must learn to filter out the information you need in a huge amount of books and literature.

Goethe has a sentence: "Experienced people read with two eyes, one eye on the paper, the other eye to see the back of the paper." "This is a kind of ability to cultivate, it must be from the surface, most of the statement, reasoning, proof, etc. to get rid of the details, find the idea, algorithm or principle behind it."

I would also like to say a little bit about how to browse the scientific references. one is to pay attention to the abstract, preface, and concluding remarks. The preface is almost the best introductory book for new areas that you don't know well. Summaries and concluding remarks often tell you what you see in this paper and what the new results are. these are helpful in understanding the paper. The second is how to find references, my advice is: try to find the latest, but not necessarily to read it carefully. If you are unfamiliar with this direction, you can find a classic paper in that direction from the references in the latest paper, which you might read from this paper.

For an extensive reading, I would like to cite an example. I've been doing research on the Game of network evolution recently. An important concept in evolutionary gaming is called evolutionary stability Strategy(evolutionary Stable strategy), which is proposed by John M. Smith . He has a classic book "Evolutionand the Theory of games", which mainly discusses ESS. I've only read two chapters to see what's going on with ESS , and find out that his method can't be used for the evolutionary game of networking. Therefore, according to his thoughts, he proposed his own definition and algorithm.

In short, the individual thinks, intensive reading, extensive reading are very important. intensive reading expands the visual field by increasing the tools. in scientific research work, both are indispensable.

the cultivation of 1.3 self-study ability

When I was in Tsinghua University, the school often propaganda "shotgun and dry food" theory, it seems that Shang proposed. It is a shotgun rather than a dry food that the school will give to the students. Dry food has a day to eat, and a shotgun will let you eat forever. This is a very reasonable statement. Take a course in school two courses ... That's dry food, and the ability to teach yourself is a shotgun. Henry Adams, a historian in the United States, said: "It doesn't matter what a man knows when he is young, but it is enough to know how to learn." (What oneknows are, in youth, the little moment;They know enough who know how to learn.)

When I was in high school, the teacher introduced a lot of interesting math or physics booklets. For example, Hua's "from the Yang Hui triangle", Wu Wenjun's "mechanics in the geometry of some applications", Bieleriman "Fun Physics", which not only learned a lot of useful knowledge, more importantly, cultivate the habit of reading and self-study ability. This ability benefits you for life.

I only had a year 08 months of college, majored in welding, mathematics only learned simple calculus. Ten years of Cultural Revolution, there are two periods of time, self-taught a few math and physics courses, a big to Dewford, and a section is divided into the mathematics teaching and learning workshops. I taught myself the complex function of Peking University, Zhou Boshun's "linear Algebra", Gretanko's "Probability theory", Elisgolz's "variational method", and Campagnetz's "Theoretical Physics" mechanics part. The method of self-study is very simple, that is, every exercise is done once. The deceased said: "Do not move pen and ink do not read", on the professional books, I changed it to: "Do not do exercises do not read."

There is a little more proud of their own English, from junior high school to university, has been learning Russian. Just in the Cultural Revolution secretly learned a little English, but also because of the peek "Chairman Mao Quotations" English version was character posters affixed to the dormitory door. To the postgraduate examination, although I did not go to the English class, but actually test the score, calculate the higher scores. These self-taught knowledge, so that I can be admitted to the Graduate School of Mathematics after the Cultural Revolution.

I feel that my life has benefited from the development of self-study ability from the middle school, I am very disgusted with the teaching of the university, such as spoon-fed knowledge, convinced that "learn to read, learn to absorb new knowledge" is the shotgun, is the real Kung Fu scholarship.

2. Research

Scientific research is the only way for intellectuals, and also the stage of intellectuals ' self-expression. How to take the stage, how to debut, how to make their own performance, this is not my pariahs actor can answer. But after all, in the scientific research for many years, have seen pigs run, speak a little experience and lessons.

2.1 reading and scientific research

As a child heard a joke: a scholar in the home searched writing articles, look at his miserable appearance, his wife said: "Look at you writing articles seem more difficult than we have children." He replied, "No, you have something in your baby's belly, but I don't have anything in my belly." "This joke is a metaphor for reading and publishing," he wrote.

When I was in the United States, my PhD was only required to take courses: I had no requirement to publish a paper because I had to take a course andtake credit. I graduated with a journal paper, a conference paper, according to domestic standards may not graduate. Some of my classmates did not publish any articles when they graduated, but still graduated. And I have taken the lessons of the Course but I have benefited for a lifetime.

personally, it is much more important to lay a good foundation than to publish several papers in the long run. Scholarship is like building a house, the foundation is not to build a tall building. I recruit graduate students, in the Master's Day, published a pile of papers of the student will not. You should study without studying, learn to piece up the rubbish paper, just like you learn martial arts do not practice basic skills, but learned huaquanxiutui, road go crooked. 工欲善其事, its prerequisite. In the basic theory study, the belly must have several excellent courses when the sharp weapon. when Lincoln was a woodcutter in his youth, he said, "If you give me 8 hours to chop down a tree, I'll spend 6 hours grinding the axe." "Only a thick, thin hair can write good articles."

2.2 Topics

For most graduate students, the topic of scientific research from reading literature,follow Other people's work began, is roughly right. unless a few talented people, the scientific research always start from imitation. But there are two kinds of imitation, one is longitudinal, is to apply the method of others, which is often referred to as the homework , as students do the same, nothing innovative. The other is horizontal, that is to find where it is imperfect or where it can be developed in parallel. In this way, you study the object and the original problem is different, need some new method or new thinking, this kind of work has certain innovation, can improve your scientific research ability.

Usually this kind of imitation is easy to make some small articles, which is necessary. In the early years heard the logic of Wang Hao's report, said:"This small article to do several, know that they will do, do not do again, to find a bigger point of the problem to do." "This larger problem should be a promising research direction.

So, what is the promising direction of research? Here are a few words to quote Mr. Prof. HO: "often have a career just started young researchers asked me, what is a promising research direction." People often tend to recommend what they are doing, but it is also dangerous to suggest that others are selfish. Mr Ho's advice is to find a real problem that people are eager to solve, and that's what interests you, but what you don't know, and devote yourself to trying to solve the problem, but not just using the existing tools you're familiar with. "

Mr. Ho mentioned several obvious advantages of this research direction:(1) Once successful, there are some ready-made people to advertise for you;(2) You can try to expand this discovery into a whole new area of research;(3 in a research area where few people are currently involved, there is no need to devote too much effort to learning the accumulated literature;(4) new projects like new mines, the same strength, the output of new mines is much higher than the old mine.

I think Mr. Ho has highlighted two points here:(1) to look for new and meaningful questions,(2) to develop and use new tools. I agree with this view and I have a similar experience of life.

2.3 Matrix half tensor product with me

Matrix semi-tensor product is a relatively proud of their own work. Matrix semi-tensor product is a generalization of matrix common multiplication, which makes common matrix multiplication can be used in any two matrices without changing its properties. For the first time in 1999 year I proposed this operation. It was mainly used to calculate the continuous system. beginning to apply it to a new and more popular problem: Boolean network analysis and control, to be successful. Relevant work was awarded by the International Federation of Automatic Control (IFAC) automatica 2008-2010 best theory / Method Paper Award.

Now, there are at least more than 10 universities, including Tsinghua, Peking University, Alexander, Tongji University, and so on, there are teachers to solve various problems with the matrix half tensor product, the international have Italy, Israel, the United States, Britain and other scholars use matrix half tensor product. At present, I mainly study the application of matrix half tensor product in game theory, especially in the network evolution game, which is a promising new field of matrix semi-tensor product.

Believing in new tools and / or new fields is the secret to generating innovative research.

2.4 Innovation concept and fantasy

The concept of innovation and fantasy is hard to define on the surface, and there is a correlation between them. So, what's the difference between them? The concept of innovation is based on a solid foundation, including your understanding of the context of the problem and the mastery of the relevant knowledge. The exploration of the truth can only be mastered by the previous knowledge and analysis of the existing conclusions on the basis, and then like Hu Shi suggested: "Bold imagination, careful verification", careful analysis, careful screening, strict reasoning, thorough argumentation. This is the rational innovative thinking.

The founder of Quantum Mechanics, Planck: "The only idea is to make the experimenter a physicist, to make the chronicle a historian, to make the ancient Codex discriminator a linguist." "It may be summed up as follows: Innovative Ideas + knowledge accumulation and academic breakthroughs.

Innovative thinking needs to dare to challenge authority, personal understanding is not superstitious authority of the speech, dare to think, dare to criticize the authority of the mistakes, to achieve the truth before all equality. But the challenge of authority should be based on respect for science. To fear the truth, the long-term accumulation of human society, has been strictly proven knowledge, is the common wealth of mankind. It's a fantasy to challenge it without knowing it in depth.

As an old gentleman, he knew nothing about the theory of gamma-MabThera, and the basic mathematics training was very scarce, so he had to solve the five-time equation and make a very low-level mistake. And when others point out his mistakes, and everyone sees clearly where he is wrong, he still does not understand and insists that he is "absolutely right". This is not a scientific exploration, but a typical fantasy. The same is true of a number of other people, who lack professional training and fantasy to easily crack the world's problems and become famous overnight.

Lessing, a famous German Enlightenment thinker and poet, once said that the word was quoted repeatedly by Hegel: "Truth is not a coin, it is placed there, and can be hidden in your pocket." Truth is a process, which is gradually mastered in the process of long and developing cognition; In this process, each step is the direct continuation of its previous step. ”

The development of natural science to today, the solution of scientific problems is more so. The most typical is the breakthrough of two major problems in mathematics in recent years. Wiles proves that Flt theorem is based on a series of predecessors ' work, including fray to convert Flt theorem into elliptic equation, Valley Mountain one Chi village conjecture, elliptic equation model and so on. Perelman proves the same with Poincaré conjecture,Ricci flow is an equation named after the Italian mathematician Ricky. When Hamilton used it to turn irregular manifolds into regular manifolds, Shing was acutely "able to use this to prove Poincaré conjecture." "Perelman was doing it in Hamilton's way, so he claimed:" I'm Hamilton's disciple. "

Marx said: "In science there is no flat road, only in the climb of the rugged path of the people who are not afraid of labor, only hope to ascend the pinnacle of glory." "This sentence is wisdom, hope in the scientific research in the overnight is idle ignorant fantasy."

3. The Way of life

"Life is a series of lessons, to understand life must go through life." (Life is a succession of lessons which must being lived to being understood.) --Emerson

"No matter what happens, you have to face Life"(Whatever reason,turn-he-back-on Lives.) --Roosevelt

3.1 Life is a long way

Life is a long journey, like a marathon, a long way to look at the amount of scenery, must not care about a moment of gain and loss, who laughs last, who laughs best. I have written to myself this passage: "Don't give up, as long as you are on the runway, you still have the chance to win." ”

If the life is million meters long-distance running, admitted to the university is probably hundred meters node, PhD graduate is probably kilometer node. The real competition in life lies in the long distance after kilometer. I don't quite agree with the saying "Don't lose on the starting line." Who saw the marathon and tried to fight it? Some students, the university as the end, even at hundred meters speed rushed into Tsinghua, Peking University, but the lack of stamina, or may be defeated.

Brockett, a professor at Harvard University, is known as the "father of geometric theory of nonlinear systems", and his doctoral dissertation is a chemistry major. A chat, I asked him: "You are a doctor of chemistry, how can you think of using differential geometry control?" He replied, "PhD is only theentrance ticket to Scientific Palace. ( Doctoral degree is just the entry volume of Science Hall.) )"

Qu Yuan's famous saying: "The road long its repair far, I will go up and down and quest." "Young people on the road to life is to prepare for a rainy day, looking to the future, lest" no foresight, there will be immediate worries ", but also down-to-earth, hard work, let" a journey, a one. " ”

3.2 failure is the best teacher

For young people, choose a goal in life and then move on to that goal. Must have the victory not arrogant defeat not hungry spirit. In particular, to withstand the test of failure, on the road of life, frustration is better than the success of teachers.

Harry Potter's author, Rowling, lectured at Harvard University on the topic "Learning from failure and using imagination" (learn from failure and making use ofimagination) . She used to be a single mother, living on social welfare, and said she was: "The most thorough loser I know." "She later became the most expensive person in Britain except the empress. "Failure teaches me a lot, and these cannot be learned in any other way," she said. Through failure, I found myself with a strong will. "Once you realize that you've become wise and strong in frustration, then you have the ability to keep your life going." You may never know who you are without being tested in adversity. "

I have suffered several setbacks on my way to life and have made myself stronger every time. Junior Middle School First grade, I just admitted to "Fuzhou first middle School", is Fuzhou the best middle school. I accidentally graffiti, wrote "reactionary slogan", was expelled from the team. It made me start working early. The first grade of the school was left in Fuzhou one, before the Cultural Revolution, I was in Tsinghua, joined the league, when the class cadres, the party activists, but also individualized to the image of life, Love is full of fantasy. The Cultural Revolution, I was named "reactionary students", like the scabies, neither of the two factions do not me. I secretly ran to Yuanmingyuan, in the rocks in a book, and later admitted to the Cultural Revolution after the first graduate student; I taught at Texas Tech University, and I resigned from home for family reasons. Then I pinned my hopes of success on myself and worked hard. Sometimes feel that fate is unfair to me, but in fact it is a bumpy life made me today.

3.3 Opportunity Only favors prepared people (what to prepare?) Why prepare? )

"The opportunity only favors the prepared person" This is one of my deepest life sentiment. a few experiences made me believe it.

five years college entrance examination Mathematics, said to be out of tricky difficult problem. The eighth question is: "Square cut two circles, a round cut left and top, another round cut right and bottom, two circles tangent, ask when two circle area and maximum?" Minimum? "The next two additional questions, one is to change the square to a rectangle, one is to change the square and the circle for cubes and balls." I believe that if I was in the field, I could not think of it. But I have done a math competition problem in Shanghai, the two-time type in the interval is extremely small. It is not difficult to solve the above problem with this method. I became Fujian province the only complete solution to this problem of students, got 119 points, is the highest score of the year. Those tricky gave themselves a chance.

Useless in the Cultural Revolution, I taught myself a few math and English, not necessarily knowing that they were useful. But later to resume the postgraduate system, they helped me to enter the Mathematics Institute, the admission rate was 50:1.

I just started using half a piece to represent the logical equation without knowing what it was for. Occasionally listening to the academic report on the Boolean network by Professor Prof. Qian of Tsinghua University in Hong Kong, it was felt that the logical half-tensor product could be used. I invited him to the dorm that night to discuss, then formed a Boolean network control of a set of theories.

In short, scholarship can not be too utilitarian, to eclectic, assiduously. Tiandaochouqin, chances are roughly proportional to your knowledge reserves. (serious consent)

3.4 experience is far more important than possession

Rousseau once said: "Life itself has no value, its value lies in how to use it." "Everyone lives, or says, to the world, how can we make this a more valuable one?"

I thought not in the fame, the splendor, but is has experienced, struggles, has a wonderful life course. At the beginning of his masterpiece, Anna Calierina, Tolstoy said: "Happy families are all the same, the unfortunate family." "Like this, we can also say:" The smooth life of everyone is the same, bumpy life is a kind of person. "Do not envy the second generation, rich second generation, to use their own struggle to compose their own unique and sensual life story."

The British writer, Stevenson, traveled around the world with a lot of lung disease and published numerous travels and short stories. He once said with emotion: "The journey of hope is more important than the arrival, and the true success lies in the progress." "(to travel hopefully is a better thing than to arrive, andthetrue success are to labor.)

Einstein himself had frankly called himself "a tramp and a freak of deviant." "Young people may learn to learn Einstein, to be a tramp, to go to different places in the world to stray, to different academic fields to wander, to grow their knowledge and talent, to be a deviant, not the rules, to take the road before the past, go to the ground, to open up new fields." If so, no matter success or failure, your spiritual world will be rich, your life will be wonderful.

3.5 The purpose of life

I have always believed that a man must have an ideal to live. I wrote in one blog post: What is ideal? It is a faint thought of the mind, a kind of hope for a better future, it is a piece of the heart of the thoughts, a desire for career and success, it is an upward knot, urging you to achieve their greatest value of life. It can't be seen or touched, but always with you. In difficult times, it gives you perseverance to persevere, in failure, it gives you to heal the wounds, new stand courage, in the face of challenges, it makes you know difficult to go astray, it is for you to guide the maze.

When I was young, I was arrogant, thinking that the world is a hero, who but myself. Decades of experience let me see, many of the people I have not seen, in different areas, to do a very good job, so that they can not be done. Finally understand a truth, everyone has their own strengths, should have their own ideals, their dreams, can go to achieve their greatest value in life. Therefore, my understanding of ideals is no longer like scientists, engineers, or even Nobel prizes ... The ultimate goal of this. It should be a process, a mindset. An effort to fight the spirit of a never give up the pursuit of always strive to achieve their best.

A classmate asked me:"What is your ideal now?" I think: my ideal is that my work can be left in history. "History is just, it will not recognize" title "," Official position ", by the history of the river has been washed and can leave the gold.

Osternovsky in the "steel is how to practice" there is a famous saying: "The most precious thing is life, life belongs to people only once." Man's life should be so through, when he was dying to look back on the past, he did not regret because of wasting time, nor because of mediocrity and shame ... "Perhaps, we should ask ourselves every day:" Today, I am in a mediocre wasting time? ”

I love Ai Qing's poem:

Even if we were just a candle,

should also be a candle into the ashes of tears to dry;

Even if we were just a match,

There is also a time to shine at the critical moment;

Even if the bones rot after we die,

and become wildfire to burn in the wilderness!

Young friends, may your life shine more brightly!

4. Living and scientific research

Confucius said: "Those who do not know better than those who are good, and those who are better than those who are happy ." "If you use it for scholarship, especially for scientific research, that's true," he said. Oneself in the academic circle to climb the life of half a lifetime, if want to say have what experience, perhaps have such a article: " when scientific research becomes a means of livelihood, scientific research is dead." "I really believe that only interest can produce truly innovative scientific research .

This time I was a visiting scholar out of the country, but out of the motive is obviously not pure: there is no PhD when the strong curiosity, and lack of passion and motivation to do research. So, doing research is like a monk knocking on a bell, as if doing for a living. Impetuous, plaintive and an inability to explain the sense of loss, condensed into a repressed atmosphere, shrouded in their own.

The imbalance in my mind makes it impossible for me to concentrate on research. Every day, when opening a book or reading a paper, the mind always can not help him to wander, often think of their own situation, that unforgettable feelings of inferiority, began to eat my heart.

My mentor is already very good enough, he gave me the subsidy is twice times more than the domestic sponsored visiting scholar. However, compared with my classmates working in the United States, I still judge if Tianrang. When they started buying a house, I had to go with the new grad student and rent the cheapest apartment. The new students have been a generation after the Cultural Revolution, they are more than a year old, English, full of youthful vitality. Already past the middle age of me, with their generation gap manifested. Being with them often makes me embarrassed.

This time in the Department for a total of four months. This period of time, desire and temptation of the contradictions dispute is always filled with my heart, let me change their minds, all day, do not know what, can not meditate into their own research. I feel that this is the least efficient period of time. Later, finally, the adjustment mentality, in the nonlinear system decoupling linearization has made a little progress, completed a conference paper. I would like to go further, but then again met with new temptation ...

Reading, scientific research and life path