Chapter 11 The second part accidentally broke into Princeton-3

When eating and chatting in the restaurant of the Princeton Research Institute, everyone always likes to sit together like a flock of like.I also sat with physicists at first, but after a while I thought: It must be fun to see what other people in the world are doing.So I took turns dining with other groups, shifting positions every two weeks. When I turned to the group of philosophers, they were seriously discussing "Process and Reality" by Alfred North Whitehead (Process and Reality) book.Their language was so strange that I couldn't quite understand what they were saying, but I didn't want to interrupt their conversation by nagging them to explain it to me.There were actually a few times when I actually asked questions and they tried to explain, I still couldn't figure it out.In the end they simply invited me to their seminar.

Their seminars are very much like a class, and once a week they discuss a chapter of Process and Reality in the way that someone reports what they have read and then discusses it.Before attending this seminar, I tried to remind myself that I was only going to observe and not to talk nonsense; because I didn't know anything about their topics. What happened at the seminar was typical—unbelievably typical, but it happened.First of all, I sat there quietly and didn't say a word, which is also unbelievable, but it happened.Then a classmate gave a report on one of the chapters discussed.In this chapter, Whitehead keeps using the term "essential object" in a very technical way. Maybe he has defined this word in the book, but I have no idea what it is.

After discussing the meaning of "essential objects", the instructor who presided over the seminar gave some speeches, intending to clarify the concept, and drew something like lightning on the blackboard. "Mr. Feynman," he said, "is the electron an 'essential object'?" So, I got into trouble again.I explained that since I hadn't read the book, I had no idea what Whitehead was referring to, and that I had only come to listen. "However," I said, "if you answer me a question first, let me know more about the concept of 'essential objects', so I can try to answer the professor's question. Do bricks count as an 'essential object'?" Woolen cloth?"

What I want to find out is whether they will classify theoretical constructions as essential objects.The electron is really just a theory we use, but it is so useful in helping us understand how the universe works that we almost think the electron is real.At that time, I wanted to illustrate the concept of "theory" by means of comparison.In the brick example, the next thing I would ask is: "What about the inside of a brick?" Then I'll point out that no one has ever seen the inside of a brick!Whenever you split a brick, all you see is another surface, "a brick has an interior" is just a simple theory that can help us understand things.Electron theory has similarities.So I asked: "Is a brick an 'essential object?'"

The answers came out in droves.Someone stood up and said, "A brick is a single, particular brick. That's what Whitehead means by an essential object." But someone else said: "No, the meaning of essential objects does not refer to individual bricks, but refers to the general characteristics shared by all bricks. In other words, the 'brickness' is the 'essential object.'" Another guy stood up and said, "No, it's not about the brick itself. 'Essential objects' refer to the concepts that form in your mind when you think of bricks. "

One by one they stood up to speak, and I realized that for the first time in my life I had heard so much genius about bricks.Afterwards, as is typical of all philosophers, chaos ensues.The funny thing is that in so many previous discussions, they never asked themselves whether simple objects like bricks are "essential objects"?Not to mention electronics! Then, at dinner, I moved on to the biologists' group.I've always been interested in biology, and their topics were very interesting.Some of them also invited me to sit in on an upcoming lecture on "Cell Physiology".Although I have studied a little biology, this is a graduate level class! "Do you think I understand? Will the professor let me sit in?" I asked.

They asked the lecturer professor Harvey (E. Newton Harvey) for me. He has done a lot of research on "luminescent bacteria".Harvey agreed, on the condition that I complete all assignments and papers like the rest of the class. Before my first class, some of my classmates who invited me asked me to look at some plant cells.Through the microscope, I saw many green spots that were constantly moving, which were chlorophyll that made sugar when exposed to light.I looked up and asked, "How do they work? What drives them?" No one knows the answer.I learned later that this was still an unsolved mystery at the time.In this way, I learned something about the peculiarity of biology: you can easily ask a very interesting question, and no one knows the answer.

But in physics, you have to study a little bit deeper to be able to ask questions that no one else can answer. In the first class, Professor Harvey first drew a very large cell diagram on the blackboard, marked its internal structure, and then explained it one by one. I understand most of what he said. After class, the classmate who invited me to sit in asked, "How was it? Did you like this class?" "Not bad," I said. "The only thing I didn't understand was the part about lecithin. What is lecithin?" The guy said in his monotonous voice: "All living things, whether animals or plants, are made of little brick-like things called 'cells'

composed of..." "Listen," I said impatiently, "I know everything you're talking about, or I wouldn't be here. What the hell is lecithin?" "I have no idea." I read papers and give presentations like everyone else.The first paper assigned to me was on the effects of stress on cells, and Professor Harvey singled it out for me because it involved a bit of physics.I fully understand the content of this paper, but when I read my post-reading experience to the class, I mispronounced all the proper nouns; However, when the word "blastosphere" was pronounced, the students in the class laughed so hard that they couldn't straighten up.

The second paper assigned to me was that of Edgar Adrian and Detlev Bronk.They confirmed that nerve impulses are sharp, single-pulse wave phenomena.Using cats as experimental subjects, they measured the voltage between nerves. I started working on this paper.It goes on and on about extensors, flexors, or excretors, and so on.I can say this muscle and that muscle, but I have absolutely no idea where they are located in the cat, or where they relate to other nerve lines.So I went to the biology section of the library, grabbed a random librarian, and asked her to find me a diagram of the anatomy of a cat.

"Cat body structure diagram?" The librarian said with a pale face, "You mean the biological taxonomy, right?" Since then, word has spread that a stupid graduate student from the biology department ran to the library Go to the "Cat Body Structure Diagram". When it was my turn to give a report, I first drew a cat on the blackboard, and began to mark out the muscles of each part.Many classmates interrupted my actions: "We all know that." "Oh," I said, "you all know that? No wonder you've been studying biology for four years, and I've caught up with you in no time." They waste all their time memorizing nouns, and these It only takes 15 minutes for everything to be checked out. After World War II, I drove around the United States every summer vacation.After teaching at Caltech, one year I said to myself: "I don't want to change to another place to play this summer vacation, I might as well try to change to another subject of knowledge." It was just after James Dewey Watson and Francis Crick discovered deoxyribonucleic acid (DNA), and because Max Delbruck's (Max Delbruck, famous physicist and biologist) laboratory At Caltech, many of the best biologists are gathered there.Watson was also invited to give a speech at Caltech, discussing the cryptographic system of DNA; I went to listen to all his speeches, and also participated in many seminars in the Department of Biology, and I am very interested in biology.It was an exciting time for biology, and Caltech was an excellent place to do biological research. I don't think I'm competent enough for real biology research, so when I plan to spend that summer on biology, I'm just going to walk around the biology lab, help them "wash the dishes," and watch See what they do, but when I went to the biology lab to explain my intentions, a young postdoctoral researcher and director of the lab, Robert Edgar, said he wouldn't let me do that. Idle around. He said: "You should do some real research work like other graduate students, and we will also give you a topic to study." Of course, I am happy to accept such a suggestion! I took a class that discussed phage.A bacteriophage is a DNA-containing pathogen that attacks bacteria.And in this class, we learn how to do research on bacteriophage. I soon found that studying biology was much easier because I knew physics and mathematics.For example, I know how atoms move in liquids, so how a centrifuge works is not too mysterious to me.And being statistically literate, I am well aware of the statistical error involved in counting spots on a Petri dish.In other words, while my classmates in other biology departments were trying to understand these "new" concepts, I could concentrate on learning about real biology. In the lab, I learned a useful technique that I still use frequently today.They taught us how to hold the test tube with one hand while opening the cap with the middle and index fingers, leaving the other hand free to do other things - like holding a pipette and carefully sucking the cyanide solution into the tube... …Wait. Now, I can hold the toothbrush in one hand and the toothpaste in the other, and open the cap, squeeze the toothpaste, and screw it back on. At the time, biologists had discovered that phages could mutate in ways that affected their ability to attack bacteria; our task was to study those mutations.However, some phages will undergo secondary mutations and regain the ability to attack bacteria. Some of the phages that have undergone two mutations are exactly the same as before the mutation, as if no mutations have occurred.Others have different variations: They attack bacteria faster or slower than normal, so the bacteria reproduce slightly faster or slower than normal.In other words, "back mutation" (back mutation) will occur, but the situation of phages returning to normal is not necessarily perfect, and sometimes they can only restore part of their abilities. Edgar suggested that I do an experiment to see if the countermutation occurred at the same position in the DNA helix.After doing a lot of complicated experiments very carefully, I found three examples of anti-mutation, which occurred in very close positions-in fact, closer than the examples that everyone has ever observed-the original function of the phage is also reply section.It's tedious research work, and the whole thing is a bit of luck, because you have to be patient and wait for secondary mutations to appear -- and that's very rare. I keep thinking about how to make phages mutate more often and how to observe them more quickly, but I haven't thought of a way yet. The summer vacation is over, and I gradually lose interest in this research topic. At this time, my sabbatical year is approaching (Note: University professors in the United States can take a sabbatical year for every few years of teaching—usually 6 years. During this year, they can do whatever activities they like at will), I Decided to spend the year in the same biology lab, but choose a different research topic.I did some research with Matt Meselson, and I teamed up with J.D. Smith, an easy-going guy from the UK.Our research topic has to do with the ribosome, a double sphere inside the cell that contains about 50 proteins and is able to transfer from "messenger ribonucleic acid" to (mRNA, messenger ribonucleic acid) to make protein. Using radioactive tracers, we demonstrated that RNA can be detached from ribosomes and put back. I carefully carried out each step, measured the data, and tried my best to control all the factors that may affect the experimental results; but after 8 months, I realized that one of the steps was too careless.At that time, the way to obtain ribosomes from bacteria was to grind the cultured bacteria with alumina (also known as alumina) in a mortar.The rest of the steps are chemically involved, all under control; but the point is that when we grind the bacteria, the action of pushing the pestle is unrepeatable, so my experiments came to nothing. I must also mention the experiment I tried with Hildegarde Lamfrom.What we wanted to investigate was, do peas and bacteria use the same ribosomes?In other words, can bacterial ribosomes make proteins in humans or other organisms? By then Lanvrom had devised a method for isolating ribosomes from pea and adding messenger RNA, which the ribosomes used to make pea protein.We realized that, "When you add pea messenger RNA to bacterial ribosomes, do you make pea protein or bacterial protein?" That would be an interesting and significant question; and our experiments were no different. It will be high-profile and will have a huge impact on the foundations of genetic biology. "I need a lot of bacterial ribosomes," Lanvrom said. Methosen and I had extracted large numbers of ribosomes from Escherichia coli for other experiments.I said, "Forget it, I'll give you our ribosomes, there are plenty of them in our laboratory refrigerator." If I had been a really good biologist, it would have been an amazing and important discovery; unfortunately I am not a very good biologist.We had a great idea, a great experiment, and a great set of equipment, but I screwed it all up; because I gave her infected ribosomes, and that's the worst mistake you can make in this kind of experiment up.Our ribosomes have been sitting in the refrigerator for almost a month, already contaminated by other organisms.If I had re-prepared some ribosomes and given them to Lanvrom with great care and care, keeping everything under strict control, the experiment would have been successful; and we would have been the first to demonstrate the universal nature of life.We'll show that the machinery that makes proteins -- the ribosome -- looks the same in any living thing.We were doing the right thing at the right time, but I acted like an amateur, stupid and sloppy in my approach and attitude. Do you know what this reminds me of?I think of Madame Bovary's husband in Gustave Flaubert's book, a dorky country doctor.He figured out how to cure the clubfoot, but the result was nothing but suffering.I'm like that inexperienced doctor! I never got around to writing a paper on the results of my phage experiment, and despite Edgar's constant urging, I never found the time.That's the problem with interdisciplinary work: I don't take it seriously.When I finally wrote an informal report to Edgar, he read it and laughed because I didn't follow the standard format that biologists use—first the experimental procedure, then the . . . Wrote a whole bunch of stuff that biologists already knew.Edgar changed what I had written into a more succinct version, but I couldn't understand it all.I don't think they ever published it, and I never published those experimental results directly. On the other hand, Watson thought my phage experiments were valuable, so he invited me to Harvard University.I gave a talk at the Harvard Biology Department on mutations and countermutations in close proximity.I told them my idea was this: the first mutation changes the protein, for example by changing the pH of one amino acid, and the second mutation changes another amino acid within the same protein, but with the same pH change as the first The reverse is true for the second mutation, thus canceling some of the effects of the first mutation—not completely, but enough to restore some function to the phage.In other words, I think it's two changes in the same protein whose chemical effects just happen to complement each other. However, that is not the case.A few years later, it was discovered -- apparently by these people who had figured out how to induce and observe mutations quickly -- that what really happened was that in the first mutation, the entire base of DNA was missing, so that the code within the DNA The order is different from before, and it cannot be "deciphered".There are two possible situations for the second mutation: one is that one base is inserted back, or the other two bases are taken away, and the result is that the code can be read again.Therefore, the closer the positions of the first and second mutations are, the less information will be damaged in the DNA, and the more complete the function of the phage will be restored. Jointly, the fact that each amino acid code has three "letters" (that is, three bases) has also been confirmed. During that week at Harvard, Watson came up with ideas and we did experiments together for a few days.That experiment is not finished, but I have learned many new experimental skills from this top expert in the biological world.That was my proud moment too!I actually gave a lecture in the biology department of Harvard University!In fact, this can be seen as a description of my life: I will always put my foot in something and see how far it can be made. In the field of biology, I have learned a lot and gained a lot of valuable experience.I can even pronounce those weird biological nouns, not to mention the mistakes that should be avoided when writing a paper or giving a speech, or realizing that a certain experimental technique is missing, etc. But what I really love is physics, and I always go back to the world of physics!