C. N. Yang: Stony Brook Masters Series

Transcript Search in video Introduction 0:05 [Music] 0:34 a theoretical physicist Cen Yang was awarded the Nobel Prize in physics in 0:39 1957 among a host of other contributions to his field his work with Robert Mills 0:45 resulted in Yang Mills Theory considered the basis of modern physics he has 0:50 crossed paths with the other great minds in his field Einstein and fairy 0:56 Oppenheimer and Teller here at Stonybrook The Institute for theoretical physics which he directed for 33 years 1:03 now Bears his name Dr Young thanks very much for taking the time I'm very happy Early Life 1:08 to be here you grew up uh in China the son of a mathematics professor yes can 1:14 you tell us a little about your early life I was born in central China but uh 1:20 I grew up in Beijing uh so my primary school years 1:27 and uh four years of high High School were in Beijing and in 1937 I was uh 15 1:36 years old uh the signo Japanese war started and uh my family moved to 1:44 southwestern China to a city called Quin which is uh famous as the end of the 1:51 Burma Road MH and uh I went to college there in 1:56 1945 I was 23 uh I want a scholarship to come to 2:02 the United States uh so I came 2:07 arriving uh on November the 24th uh in New York 2:13 City uh because at that time there were no commercial traffic between China and 2:18 the US and the only way for me to come from kumin in southwestern China to the 2:26 US was to fly to Kolkata in India and they wait for a boat a ship one of those 2:35 uh troop transport ships of uh the American military forces 2:42 which were used to transport the over million American soldiers in the China 2:49 Burma India theater from that area to the United States so I waited for two 2:56 months in Kolkata for for a birth on one of 3:01 those troop transports and uh the ship was about 5,000 tons and we 3:09 went through the Mediterranean and the Atlantic Ocean where we got into a storm and I 3:17 remembered I was vomiting so much and I said to myself maybe this trip is not 3:23 worth it but anyway I arrived uh in New York and uh went to Chicago and became a 3:31 graduate student at the University of Chicago that was quite a quite an adventure for a young man yes it was and 3:39 of course uh to come to the United States from a completely different culture was I wouldn't say it was a 3:46 shock but it was uh it required some adjustment was it your um your knowledge Education 3:53 of physics that got you U that sort of bridged that that divide uh 4:00 uh yes I had a very good uh education both uh in college in kmin and later for 4:09 two years in the same University as a graduate student earning a master's 4:15 degree um my level of Education in China was uh very 4:20 Advanced uh such things like uh quantum mechanics I've studied uh thoroughly in 4:26 China so when I got to the University of Chicago which was uh which had at that time the 4:33 world's best physics department uh I found that uh the 4:38 quantum mechanics course offered in Chicago was not as uh deep really nor as 4:46 uh detailed as the course I had in China so I had a head stall in some sense and 4:54 uh so I earned a PhD degree in Chicago in 1948 Atomic Bombs 5:00 I was thinking that um when you made your journey to the United States it was 5:06 at about that time that the United States had dropped atomic bombs on Hiroshima and Nagasaki yes how did that 5:13 how did that affect you if at all in your in your field and as a 5:19 person uh oh it has a profound effect uh you know uh China was fighting the 5:27 Japanese invasion from 37 to 45 uh eight 5:33 years and um uh China was very weak at that time 5:40 and uh it was a miserable time and the Japanese uh were very brutal you may 5:45 have heard of this uh massacre in nin yes uh 5:51 so uh and nobody had any inclin that uh there was this uh new weapon developed 5:58 in the United States uh in fact I understand most of the people in the US didn't know about it 6:05 either right and so the morning in August when the bomb was dropped when 6:12 the radio announced the news uh it was a great Elation for the people in 6:20 China uh because uh everybody knew that's the end of the misery of the 6:26 eight years of War uh uh I remembered uh I was uh I came out of uh our house 6:37 rented house and got onto the street and suddenly I saw many people uh exploding 6:43 firecrackers you know in the Chinese custom if you have something to celebrate you you have hundreds of 6:52 firecrackers and uh then I got hold of a newspaper and then realized uh what 7:00 happened uh of course uh that was a great event for the American people but 7:06 I would say the American people did not suffer as much during the war as the Chinese people and as a consequence of 7:13 that the happiness and the Elation that was felt in China was proportionately 7:21 higher did you understand the physics ramifications of of the atomic bomb at Atomic Bomb Physics 7:27 that time uh the General Physics 7:32 uh uh principle that uh one can generate tremendous amounts of energy by Neutron 7:41 collisions uh was known since uh 38 and 39 and uh that in fact even got into 7:50 textbooks but uh the detailed uh procedure by which you can 7:58 uh do that was a very complicated Engineering Process and 8:04 uh uh you probably know that uh it was so difficult that the 8:12 Germans in about 1944 or 43 decided uh it uh cannot be done 8:20 during that war so they abandoned that project uh fortunately they did uh and 8:28 the United States it was uh picked up uh first because of a letter iron 8:36 wrote to president Rus but more because of uh the 8:42 fear among the American government and the F phist 8:47 especially that the Germans might uh get it first so they devoted the 8:55 wholehearted effort at Los Alamos to do this uh it's uh a most important event of 9:04 course not only for the 20th century it's one of the great events in the 9:11 history of mankind you and I certainly don't wish to to U make this all about the bomb but 9:18 it's it's it's uh sort of coincidental that you went to Chicago the University 9:24 where much of this work was done um and uh one of your mentors there was fairy I 9:31 believe yes tell me a little about fairy uh enrio fairy was born in two in 9:39 1901 in Italy uh at that time Italian physics 9:45 was not so great and he was a precocious 9:50 young man and he alone uh lifted ital the level of 9:56 Italian physics to World standards at a very young 10:02 age uh he was a remarkable person and I had uh said that uh familyy was a person 10:11 with both feet on the ground how so uh in the sense that um he was very solid 10:19 he looks like he was a solid person and he is uh when he uh speculates on something 10:29 you know that uh it was based already on concrete thought which he had already uh 10:37 been thinking about therefore his words carry Authority because you know that 10:44 these are not the random or of the top of one's head kind of 10:51 remarks uh and he was a great theorist 10:56 as as well as a great experimentalist you know in early centuries uh many 11:03 great physicists were both theoretical and experimental but by the 20th 11:09 century um theoretical physics has gotten so complicated experimental 11:15 physics has gotten so complicated so very few people could do both and uh Relationship with Fermi 11:22 Enrico FY was the last great physicist who contributed first class work 11:29 to both sides how was your relationship with him oh very close uh you see when I got 11:37 to Chicago very rapidly everybody found that this young man from China was 11:43 extremely well trained uh so I had a very close and 11:48 warm relationship with the familyy 11:53 uh Mrs FY uh the fies had two kids 12:00 and one of them the older one Nella was uh College 12:06 age so the family is always uh hold a 12:11 square dance party in their house and I was there many times and got to know the 12:18 family uh very well uh in later on in 12:26 1949 uh FY and I wrote a paper together uh it's called our Meson 12:34 Elementary particles and I was very happy to see 12:39 that that paper is still referred to today because uh we were the first to 12:46 publish a paper saying that uh what is known as a Pion uh may be a bound state 12:55 of a uh nuclear with an anti-nuclear these are probably two technical terms 13:00 but anyway uh we wrote a paper together and uh so I was 13:07 the one of the favorite students of family in Relationship with Oppenheimer 13:13 Chicago you of course knew uh Oppenheimer you at The Institute for advanced study with Oppenheimer yes tell 13:20 me about your relationship with him uh everybody knows that the opah 13:26 hammer became very famous because of it uh uh direction of the atomic bomb 13:33 project during the war and in 1957 47 he 13:38 accepted the the directorship of the institute for advanc studies and um in 1949 he came to 13:47 Chicago to give a talk about a new uh 13:53 development in physics called the renormalization I will not uh explain 13:58 why what it is but anyway that was the hottest uh topic around that time so I 14:05 was fascinated by his talk and I knew that uh starting that fall the fall of 14:13 1949 there'll be many experts on renormalization uh at his Institute in 14:21 Princeton so I applied to become a post talk at the 14:26 Princeton and uh abam accepted me so starting in 49 the 14:34 four I went to The Institute for advanced studies I was originally just 14:40 going to be there for one year as a post do and returned to Chicago but uh I remained and allog 14:49 together I was in Princeton for 17 years from 14:55 1949 to 1966 and uh as you know the institute for 15:01 Advance studies was a well-known Ivory Tower in the best 15:07 sense of the word their Scholars uh do their 15:12 research uh without been bothered by committee work without being bothered by 15:18 graduate students and indeed I took great advantage of that that was the 15:25 period that 17 years was the period I did my best uh research work I I Stony Brook 15:32 understood that um Oppenheimer tried to uh convince you to replace him when he 15:38 left the Institute but that instead you came here to Stonybrook which was barely 15:43 uh barely peing out of the ground at the time what what what happened there uh yes uh what happened was the 15:51 following in 15:56 1965 uh first before President Kennedy was uh 16:04 assassinated uh he named alamer as the next enrio FY Prize winner 16:14 the enrio FY price was a presidential award it was originally awarded to fairy 16:23 because uh F was Dy and they quickly created this price and gave it to him 16:29 before he died in 1954 and afterwards many distinguished 16:35 uh people who contributed to the US uh worldtime scientific work got the uh 16:43 price including beta including tellor uh 16:49 Etc and uh probably or very 16:56 likely because uh president President Kennedy wanted to 17:02 uh erase the Sorrows that the the US Meed out to 17:11 opah hammer in the opah hammer hearings of 1954 so he decided to give it give the 17:18 next one in 62 to obah hammer but before that transpired he was assassinated uh 17:27 Kennedy was assassinated so then Johnson became 17:32 president and uh in fact the rumors were that uh many of the people who are 17:38 against op Hammer uh tried to convince Johnson not to give that award but the 17:46 Johnson did not listen to them so there was a ceremony uh and alamer did win the 17:53 world so that was uh I think it was 196 63 or 18:00 64 but anyway uh that was at the time so by 18:06 1965 uh aaham had just uh had this uh uh great event of the United States 18:17 uh government essentially saying implicitly we are sorry right and we 18:24 apologize now upen Hammer is the director of the insute intitute had great difficulties with the 18:30 mathematicians in The Institute that's a long story I'll not bother you with the 18:36 details he was a director but the mathematics Group which is the 18:42 strongest uh at the institute at that time and still today uh were unhappy with him in my 18:51 opinion uh they were wrong in a accusing uh upen hammer 19:01 of uh not favoring mathematics but anyway they made op Hammer's life very 19:06 difficult for many years so one day in 65 I remember opah 19:13 Hammer dropped by my office and said uh Frank uh I'm thinking of uh retiring as 19:21 director how do they think about it I was uh 19:26 surprised uh but I thought about it for a few minutes and I said uh I think this 19:32 is a good decision because I said you have been at the institute for a long time now and 19:40 this is the right moment because a there is a law in the opposition on the part 19:48 of the mathematicians against you and uh In the Heat of great debate 19:54 it's difficult for you to say I want to retire and secondly the United States government 20:03 has essentially apologized to you uh this is the right moment so he thanked me 20:10 for my opinion then he said uh I want to 20:16 propose you as my successor my instinctive reaction Deciding to become a director 20:22 immediately was that uh I don't want to to do it because uh I'm not a 20:29 administrative type it's uh uh so I told 20:36 him I'm honored that uh you thought so but uh I'll think about it for a few 20:43 minut for a few days so I thought about it and uh 20:48 eventually I wrote him a letter saying that uh uh how 20:56 I am not sure I'll be a good director I'm however very sure that I 21:03 won't enjoy the life of being a director so that's the end of that part of the 21:09 story but just around that time a little bit uh before my final decision but 21:16 after he had mentioned his proposal to me uh John tol who had just become who 21:23 had just been nominated as the president of uh stook uh came to visit me and 21:30 asked me to join him in stook to develop 21:35 stook into a uh great research 21:40 University uh so uh when I wrote that letter to OB 21:46 Hammer I had already decided with my family that I'm going to move to 21:53 stook that was in 65 and you came on the pretty much on 21:58 the promise that a great research institution would be built here because 22:04 there was none at the time yes uh you of course know that 22:09 um ston began about 50 years ago but it was uh 22:16 in another campus and the the real expansion 22:22 started uh when it moved here and the great expansion started when jto came in 22:30 65 and 66 and uh that was a great period of uh 22:38 expansion and I think uh what you see today 22:43 uh have all in many senses originated with the few 22:51 beginning steps that uh John to and his uh Administration put in place 22:58 and that you helped him with uh yes in some Einstein 23:04 respects you knew also Einstein uh yes I went to The Institute 23:10 as I told you in 1949 uh he was uh 70 years old at that 23:16 time and he had just retired but uh he lived close to the Institute and 23:25 he would still walk to the Institute every they he he didn't drive and uh he 23:31 would walk uh to his office and then stay a 23:37 few hours and then walk back now uh at that time uh I irance 23:44 position in physics was towering it's I had said 23:50 uh repeatedly that the Newton and Einstein are the two greatest physicists 23:57 of all four times and uh but uh he was at that time 24:05 no longer working on the things that we were we young people were interested in 24:11 so we didn't so much uh bother him uh however I did 24:17 hear uh two lectures by him and uh in 24:24 1951 I think uh I think 51 or 52 uh he sent his 24:30 assistant Brewer cman uh to me and said uh you just 24:37 published a paper in the physical review uh about uh gas liquid uh how gas became 24:44 a liquid how upon Cooling and uh Professor Einstein would 24:51 like uh to talk with you about the the paper wow so I went to see him and uh we 24:59 must have spent an hour and a half together and I was very much Ed by his 25:05 presence uh I didn't get very much out of that uh conversation I only remembered he repeatedly drew a curve 25:14 which was very famous due to Maxwell a great physicist of the 19th 25:20 century and uh indeed uh Einstein's uh Einstein was 25:28 deeply in the tradition of old physics of classical physics two branches of 25:34 that uh statistical physics and uh electrodynamics were his uh great uh 25:43 fors and uh using this tradition using 25:49 his uh deep perception in these two 25:55 areas he launched the two and a half revolutions for physics 26:01 in the 20th century two and a half yes which was the half uh quantum mechanics okay the three 26:09 revolutions were that's generally accepted as the greatest revolution in 26:16 physics uh after Newton it was special relativity general relativity and 26:22 quantum mechanics uh special and general relativity 26:28 were invented by him MH essentially alone quantum mechanics was the work of 26:36 many people and so I count that as half a revolution okay by 26:42 Iran I I I'm unable to plumb the depths of physics or scale the heights of YangMills Theory 26:49 physics whichever it is um but I wonder if you could explain to us 26:55 non-physicists um the Yang Mills 27:01 Theory uh you know what the fundamental physics 27:08 is about is uh to ask uh how 27:15 matter uh is put together in the 19th century finally 27:21 people realized that everything is made of uh atoms and molecules in the 20th 27:28 century we learned that the uh molecules are made of atoms atoms are made of 27:36 protons and electrons and neutrons but uh what are protons and 27:41 neutrons made of now we know they are made of quarks so that is one aspect of what we 27:48 do namely we want to take matter apart and look at the 27:55 constituents but there's another part of the Endeavor namely how these parts are put 28:03 together the reason that they are together is because there's a force between them force is in Daily Language 28:12 in physics we call it the interaction so the question is what are 28:17 the interaction between these constituents uh interaction of 28:24 force uh it's well known already since Newton's time there's gravitational 28:31 force and uh through the 19th century we know there are electric and magnetic 28:37 forces in the 20th century we know there are two additional kinds of forces they 28:44 are called nuclear forces which are responsible for the atomic bomb nuclear forces nuclear forces and the weak 28:51 forces which are responsible for such things like radioactivity 28:58 so there are now four types of forces the question is what are the precise 29:03 nature of these uh four types we know that the gravity through Newton is a 29:11 inverse Square law you probably learned that in high school physics so you might 29:16 say that the basic question that uh one of the basic questions one of the 29:21 fundamental basic questions we face is how are these three other forces 29:28 structured they are not inverse Square laws but what are they and that's where 29:35 the young M Theory or gauge Theory comes in gauge Theory gives a 29:43 principle which uh uh governed how these forces are 29:51 structured mathematically precisely and uh when M well 29:58 originally in 1918 and 1919 stimulated by Einstein Herman v a 30:07 great mathematician uh proposed what is called gauge Theory uh he used that to 30:15 describe uh electricity and magnetism and that was successful but it does not apply to the 30:22 other two the nuclear forces and weak forces MH and what Ms and I did was we 30:30 generalized what the V did and that becomes a general principle 30:38 of forces of why they are these forces including 30:44 gravity and that principle is now called the gauge principle M and the gauge 30:50 principles detailed mathematical structure is what uh we wrote down in 30:56 1954 at the time that we wrote it down nobody 31:01 believed uh that was it was important and we didn't know it was that important 31:08 but we said that this is a beautiful idea and the mathematical structure is 31:14 very elegant so we published a paper about it and uh then 20 years later 31:20 various experiments showed that that in fact was approximately the right 31:26 direction then after struggling for another five years it became clear that it's not just approximately right it is 31:33 exactly right so that became something which uh uh is now the universally 31:42 accepted principle of how these forces are 31:47 formed 1954 yes how do you feel about that fact that 31:55 50 years later something that you created that you propounded has been so 32:01 so fundamentally U has so fundamentally changed to your field well of course I 32:07 feel good about it but uh I tell my 32:14 students that uh the structure of 32:20 uh uh everything uh often times has a hidden 32:27 uh Beauty in it if you can sense vaguely some of 32:34 these Beauty uh do not let go uh the reason that in 32:42 1954 Mir and I were able to do it as I told you it was not in agreement with 32:49 experiment and nobody believed this but we saw the beauty of the structure so we 32:55 wrote it down the Elegance of structure that's right it's uh it's a oh by the 33:00 way I should add the following uh and that has something to do with stone 33:06 book uh okay this uh y m theory was published and uh gradually originally 33:15 people didn't believe it gradually more and more people see the beauty of it so people began to work on it but it was 33:22 only in the 70s that it was confirmed by experiment 33:27 and uh so by the 60s there 33:32 were not many papers but I would say every year there'll be 10 papers 20 33:38 papers about it and uh I came to Stone in 33:44 1966 and one day it must be 68 or 69 I was giving a talk I I was giving a 33:50 lecture no I was giving a course on general relativity it's a graduate uh course 33:57 and I wrote down on the Blackboard uh one long formula a famous formula called 34:03 the remon tensor Reon was one of the greatest mathematician of the 19th 34:09 century and Reon tenser has something to do with the Einstein's gravity Theory so 34:17 I copied down on the Blackboard the P this uh long P long formula of the remon 34:25 tension as I was coping down it suddenly flashed through my mind that the 34:32 structure of this uh reong equation is very similar to the equation that Ms and 34:38 I had written down when we wrote it down in 1954 we didn't notice uh we were not 34:45 uh doing general relativity so we didn't notice there was any similarity but uh that uh Le during that 34:54 lecture I found that they were very similar so after the class I went to my office and checked in detail and sure 35:01 enough they were not just similar they were exactly the same if you define some 35:06 quantities correctly so I was a bit excited but I didn't understand it and 35:12 uh so I went to see Jim Simons Jim Simons as you know was the young 35:18 department chairman of mathematics at Stone book and he was a great uh 35:23 geometer so he knew uh remon in Geometry very well so I went to his office we 35:30 were still in that old red brick building both his office and mine so I 35:36 said Jim uh here's the reing formula that you are 35:42 very acquainted very familiar with and uh some years ago M and I wrote this 35:49 formula look they are very similar and uh he thought about it for a 35:54 while he said that yes yes that's it's not strange they are both fiber bunders 35:59 so I said what's a fiber bundle uh so he gave me a book uh written by a famous uh 36:07 princet the mathematician called stin Rod it's called fiber bundus so I went back with 36:16 book and uh but the book was impossible for me to understand uh the 36:21 mathematicians have a tendency to write very dry uh 36:28 uh very abrupt statements they are precise but there is 36:33 no flesh to it so it's very difficult to it's all bones and is it's impossible to 36:40 understand so I didn't understand so I went back to Jim and said look this book 36:46 is useless for physic but uh we want to understand what this fiber bundle 36:52 business is about and uh could you explain to me me what it is he said the fiber bundles is 37:00 a new thing in mathematics too but earlier than in physics in starting in 37:05 the 40s there were already many papers in mathematics in fiber bundles and it's 37:12 now a important branch of geometry and so I said uh could you give 37:19 us some lectures understandable to theoretical 37:24 physicist he said yes so he gave a series of lunch lectures uh The Dictionary 37:32 very uh informal there may be 10 of us 37:38 uh faculty and graduate students of uh The Institute of theoretical physics 37:44 here at Stonebrook and uh as he must have uh talked for about a a whole month and 37:52 that was very useful for us so at the end of that um we decided to give him a gift for this 38:01 uh uh series of lectures so we chipped money 38:08 together and decided uh to buy something for him and I went to Irving CW a 38:16 mathematician whom I knew very well I said Irving we want to give a Jim a gift 38:22 what should we buy he said the Jim cannot uh spell give him a 38:28 dictionary so we bought a big dictionary and gave it to Jim and uh he told me 38:34 recently that he's still using it but uh what we learned from Jim in 38:41 those uh lectures were very important not only 38:47 for me not only for stoneberg but in fact it launched a new 38:55 trend and that came about this way after I understood the gist of uh what the 39:03 mathematicians were doing with fiber bunders I realized indeed both general 39:10 relativity of Einstein M and uh gaug 39:16 Theory were fiber bundles so I wrote a paper with TT of 39:23 Harvard immediately after that in which we we explain in 39:29 detail the relationship between the mathematicians ideas and terminology and 39:35 the physicist ideas and terminology and so we made a little dictionary the little dictionary had only maybe 15 39:43 entries on the left side are the physicist terminology on the right 39:50 side all the mathematicians terminology and there was an exact correspondence so 39:56 we call called it the dictionary but there's one item which uh physicist used uh 40:04 repeatedly its technical term is called source source actually was due to the 40:12 idea of source was due to Ampere you know the electric Uh current three amp 40:20 five amp yes that was named after the great French physicist 19th Cent 40:27 Empire and uh uh 40:34 now in physics Empire's idea of a source was 40:40 a crucial concept so we have to have that in our dictionary on the physics 40:46 part but on the mathematics part I went to ask Jim what do you call this he said 40:53 we don't deal with this concept so we left that the blank so it's a dictionary 40:59 with maybe 15 entries on one side 14 entries on the other side and nothing to 41:04 correspond to Source yes but then 41:10 uh ye singal from MIT a distinguished mathematician came to visit I had known 41:17 him so I gave him a copy of our preprint and he looked at it and there's this 41:23 blank so he thought about it and decided that is a very interesting 41:29 concept and they should deal with it they somehow in their 20 or 30 years of 41:36 dealing with the fiber bundles had never touched on this idea so he went to England immediately 41:45 and he was a great collaborator of uh a perhaps the greatest mathematician today 41:52 in Great Britain uh Michael AA it's now sir my CR at that time he was 41:59 not a sir yet and uh so they looked at it and found that this concept that they 42:06 never used but we dealt with since ampire was most interesting that became 42:13 now a new branch of mathematics so they wrote a paper and because of the 42:19 prestige and the fame of a teer and singer many young mathematicians all 42:26 began to look into this and now it is a thriving branch of modern mathematics 42:32 what do they call it uh well there are many names in particular a student of AA 42:40 called uh Donan uh did the Pioneer working it so 42:46 it's called donon Theory but the all those are related to that blank 42:53 spot so in some sense you know know in the first half of the 20th century 43:00 physics and Mathematics were divorced uh in early centuries physics 43:06 and Mathematics were in close collaboration but in the first uh half 43:12 of the 20th century the mathematicians became more and more 43:17 abstract they in fact were very happy that they in fact one of them wrote a 43:23 article saying that the greatest contrib tion the greatest achievement of 20th 43:29 century mathematics was that it finally liberated itself from the shackers of 43:36 physics that was by a famous mathematician but with this uh fiber BND 43:43 business uh the mathematicians and the physics are not coming together again so 43:49 if you want to say how did that coming together come 43:55 about I would say that uh it has something to do with uh me and Jim and 44:02 that Blank Spot in that dictionary and with the stoner book so we are very 44:08 happy that uh Jim continued to be interested in physics and math and you 44:14 know now he's a billionaire and uh he just announced he would give her $25 44:19 million to St that's great yeah so you I mean you have this is just 44:26 another way you have made connections in in your life uh not only connections 44:33 having to do with matter but also yes uh yeah interdisciplinary connections as 44:39 well uh I moved back my former wife 44:45 passed away in 203 I moved back to Beijing when I was growing up in Beijing 44:52 as I told you before my father was a Prof professor at the Singa University 44:58 in Beijing uh one of the most uh prestigious universities in China and so 45:04 I grew up on that U campus uh in 19 in 203 after my former 45:12 wife passed away I moved back to that campus and now I'm a professor of 45:17 physics on that campus and the Jim and Maryland came to 45:23 visit us in 20 45:28 01 that's before my I moved back I was uh already visiting that campus very 45:35 frequently and Jim came and uh I remembered uh what happened 45:43 precisely after his visit I came back and he came back and I visit him and in 45:50 his office here in soket I said uh what's your impression 45:55 of China oh he said uh he was very happy with the 46:01 visit he said I figured the greatest problem in the world today is 46:08 poverty and here I see 1.3 billion people pulling themselves uh out of 46:15 poverty uh by their own bootstraps that's a great contribution 46:20 not only to themselves but to the world so they deserve uh 46:26 our help what do you need so I said uh uh we have many 46:34 visitors in Beijing but the housing was lousy uh how about helping us 46:41 to have some uh visits housing so he gave a million dollars and 46:48 now that the complex prices are still cheap in China 46:54 so that uh $1 billion sorry $1 47:00 million uh is suff sufficient to have nine very nice Apartments build and is 47:08 called CH Simon's hall because uh one of his great contributions to math and 47:15 physics was a paper he wrote with churn in the 1970s and uh he and Maryland recently 47:23 went to uh Beijing and uh open that Hall so I think that uh 47:31 through the math physics connection uh there is now a Stonebrook 47:38 T connection too I wanted to ask you um you mentioned Differences in Education 47:44 that when you came to the University of Chicago from China you were you actually 47:50 already knew some of the things that they were teaching at the time you were 47:55 very very well trained how do you U how do you see the uh the differences in 48:01 education in in in the United States and in China today that's a very important question 48:09 and I've been reflecting on that uh I think there are very 48:15 fundamental differences and uh these fundamental differences uh show up on each 48:23 side uh good points and bad points uh you know that the the 48:31 newspaper said that President Bush just uh appointed the uh committee to study 48:39 how to address the problem of uh mathematics education in the primary and 48:48 secondary schools in the United States why because uh in many many 48:56 many uh high school student mathematics examinations International 49:04 examinations with maybe 30 Nations the US always is near the bottom it's the 49:12 Asian countries that are at the top so of course that gets uh the 49:19 Educators and the mathematicians worried here and that's why this uh 49:24 appointment uh why why is it that uh the US uh high 49:34 school education in mathematics uh is not as good it's because the 49:41 whole educational philosophy and system are different the kids here 49:48 [Music] are uh are more treated as uh adults even 49:58 though they were young in China if you have a 50:05 eight-year-old uh child and say you should do homework he or she would just 50:10 go to do the homework here if you have a eight or nine year old child and you say 50:17 you should do homework he or she would say I don't want to do it why not it's uninteresting 50:26 is boring the concept that doing homework might be boring does not exist in 50:34 China so if you ask a child to do it he would just do it is this a matter of 50:39 discipline or something uh yes it's a discipline which is in the air so that 50:46 the concept that that that a child would only do something that he or she is interested in does not exist so that 50:54 that's the difference now the consequence of that is that the kids are well trained they do lots of mathematics 51:01 exercises okay so that means the Chinese system is good no because if you go to 51:07 China they're all discussing this Chinese system is no good all the kids 51:12 are trained too much a they have no free time and they cannot develop uh other 51:18 interests B they have the tendency to become robot-like they don't think for 51:26 themselves so they are discussing Iden finding item how to change that system 51:31 to be more like the American system so after you have observed both 51:38 these two you realize that this a very complicated thing it's in fact if 51:43 President Bush asks me what this mathematics committee can do I would 51:50 tellar him they won't be able to do anything because it's not the education 51:55 system it's the whole society it's the whole value judgment it's whole idea of 52:03 how uh you educate the philosophy behind education 52:08 is different and um so in fact I believe that all that one can do on each side is 52:17 to make small changes so as to most of the kids here uh are not uh 52:26 interested in mathematics I would say uh that's okay 52:32 there's no reason for so many kids to be interested in mathematics but the system must be such that for those who could be 52:40 interested who could in fact be extremely interested you must provide the opportunity for them to get into it 52:47 on the other hand in China I would say that don't train all these kids all the 52:54 time it it's too straight lighten up yes 53:00 uh so the I think a comparison of uh the educational system 53:07 the educational philosophy in the orient and in the United States is a very 53:13 interesting and very deep subject given all that you've said why would a why 53:19 would a a student in China come to Stonybrook to study oh mostly 53:27 because graduate school in the United States is uh the best in the world 53:34 today we were talking about in the last few minutes about primary and secondary schools when 53:42 it come to graduate education the the US the best us uh graduate 53:51 schools are absolutely the best in the world so so uh I always say that uh if 53:59 you have a bright uh child the best thing is for him to get a 54:07 good high school education in China a college education in China and get a 54:14 good graduate education in the United States I myself benefited exactly from 54:20 that I had a very good college education in China where the professors are very 54:30 devoted they are very responsible they lead you through difficult 54:36 things uh going to Great depths and uh covering large areas that's why when I 54:43 came to Chicago I had a tremendous Advantage compared with my fellow 54:49 American graduate students uh but on the other hand when I came to Chicago 54:55 I learned how to explore the Frontiers how to be creative in your 55:05 thinking about the Frontiers problems so I got the best of uh both words and I 55:12 think that is I was fortunate and I would recommend that to any young person 55:20 who especially is interested in the Sciences Experimental vs Theoretical Physics 55:26 I think this is a good note to uh to turn it over to our audience and uh and find out if there are questions u in the 55:33 audience U if you'd step up to the microphone if you have a question for Dr Young uh you mentioned earlier that uh 55:41 as time went on experimental and theoretical physics uh grew apart because of growing complexities within each of them I'm curious how you uh 55:49 yourself decided which which one to go into or did it just sort of happen naturally with the work you were doing 55:55 experimental versus theoretical physics yes how did how did how they grew apart and how did you adapt to that uh no how 56:02 did he actually decide to go into theoretical physics how did you why did you decide to go into the theoretical 56:08 Branch uh as I said experimental and theoretical physics have both become so 56:16 complex by the mid the 20th century uh 56:21 it's almost impossible to be EXP in both both and as I said the 56:28 family was the last physicist who made first grade contributions to both 56:34 sides now I myself when I came uh to the United States I knew that I had a very 56:41 good grounding in theory I also knew that I had uh almost no knowledge in 56:49 experimental physics so I said I must uh broaden my educational basis 56:55 so I decided I should write an experimental thesis here and 57:02 uh I so I worked in fact at Chicago for some 18 or 20 month months in the 57:11 laboratory of Professor Allison Allison was uh making 57:18 a at that time a large accelerator it's about the size of this room uh it's a 57:25 400 kilovolt of water circuit and uh so he had maybe five or 57:33 six graduate students and I became one of them but quickly I learned that I'm 57:38 no good at uh experimental physics uh when things go wrong I do not 57:46 know why they are wrong and uh I of also 57:51 often times turn the wrong knob and uh do some very bad things to various 57:58 things so my fellow graduate students were all a little bit uh worried when I 58:03 get close to any equipment uh but uh we were on good 58:08 terms because uh I could solve theoretical problems for them very easily uh but anyway after 18 or 20 58:17 months of work uh I was very frustrated because uh uh Allison gave me a problem 58:25 and uh the experiment I was doing on that problem was not uh going well and 58:32 uh one day tellor came I had uh be in contact with tellor in theory and tellor 58:40 said uh I understand your experiment is not doing well I said right he said why 58:46 do you stick to experiment you had already written a paper a short 58:51 paper uh in theory uh I can sponsor that uh as your thesis if you make it a 58:59 little bit longer so I said uh thank you very much I have to think about this 59:05 because it was uh not according to my plans for so long thinking about it for 59:12 a few days I finally went back to him and said uh I accept your uh suggestion 59:19 and uh that was uh a very important thing in my life namely to learn what 59:27 I'm good for what I'm not good for any other 59:37 questions I have a question because both of stoneberg and chinai University are 59:43 very great University in the world and as a professor you have taught all of the students in both universities and 59:50 how could you how could you compare the students in both of University one is in 59:56 America and another is in China thank you comparing the uh the students in 1:00:03 China at the college level with the students in America at the at the college level yes I me undergraduate in 1:00:10 undergraduate yeah yes how would you compare undergraduate you spoke of that's a very important uh topic uh 1:00:17 especially since uh I have some firsthand observation um I taught 1:00:25 twice in ster book freshman physics and I taught uh for one semester 1:00:31 in 204 uh freshman physics at s 1:00:37 University so I have a firsthand knowledge about the Freshman students in 1:00:43 physics here and in Beijing uh uh T of course is 1:00:52 uh one of the most difficult to get into universities in China and uh so I found that uh there 1:01:02 are two differences difference number one is that the students in uh 1:01:09 Chena are almost all very well trained they 1:01:15 did lots of exercises in high school so such things like uh analytic geometry or 1:01:23 trigonometry is no problems for them here uh at least half of my students 1:01:31 here were not well trained in analytic geometry 1:01:37 or trigonometry they know the definitions but they cannot manipulate 1:01:44 because they didn't do enough exercise so the first difference is that the the 1:01:50 high school training in China is much more rigorous than here the second 1:01:57 difference is that the the students in China in Singa 1:02:05 University were very mature and very motivated they 1:02:13 were they knew they have to work hard they sort of uh 1:02:18 appreciate uh that uh what they want to do 1:02:25 and they go full force at it for the stoneberg students I would say at least 1:02:31 half of them we still sort of uh wandering around without any specific 1:02:37 aim in life this is I have thought about this this is um again a product of the 1:02:46 difference of uh the two societies now you cannot say which one 1:02:52 is necessarily better the Chinese system is better in training 1:02:58 a lot of people who would uh uh mature 1:03:04 who would get channed into some uh wake of way of life which would 1:03:10 make them a useful citizens but uh the American 1:03:16 system uh is more free and so therefore the people's outlook on life on 1:03:23 everything is uh uh is less 1:03:29 restrictive and uh the best of them are given enough opportunity so that they 1:03:36 can prosper look at Bill Gates Bill gas is able alone to create uh trillions of 1:03:44 dollars not for not only for uh his company for the whole world so that kind 1:03:52 of uh uh Innovative Spirit of free spirit is the 1:03:58 kind of things that the United States educational system and Society is uh 1:04:04 good at fostering and that's that's true all over the world I think the Europeans 1:04:10 the Japanese all Marvel at the great success of the United States system 1:04:17 which produced all these uh uh tremendous Innovations and as a 1:04:23 consequence wealth okay thank 1:04:28 you questions um Professor uh you said uh to 1:04:34 sense the beauty is important in the scientific research uh I want to ask uh 1:04:40 whether you have uh any tricks to sense the beauty can you tell us some you said 1:04:47 the importance of sensing the beauty or the the Elegance of in scientific work 1:04:54 do you have any tricks uh that help you to uh to spot the beauty or the the 1:05:03 Elegance uh the the direct answer is certainly 1:05:08 no uh I think for a young 1:05:14 person it is uh important and that uh the American 1:05:20 system is uh good good for this 1:05:27 to allow uh oneself to be interested in in quite a 1:05:35 number of things and uh to 1:05:42 perceive some things some areas uh some 1:05:48 directions that he or she is particularly interested in and and uh if a person at a young age 1:05:58 could uh latch on to something that he or she is interested in and uh fully 1:06:04 develop that that may be the way he or she would find the Elegance the beauty 1:06:13 the usefulness of some things uh it's uh the Chinese system is 1:06:21 not good for this the Chinese system has too much of a 1:06:28 tendency to impose what the children what the school 1:06:33 what the society want the young person to look 1:06:40 at and uh discourage him or her to Branch out 1:06:47 the American system is better in this respect so it's 1:06:52 uh uh uh I think there are good aspects 1:06:58 and bad aspects of uh each system when you choose is to discuss different 1:07:08 directions of what you want to push Dr Yang thank you very 1:07:14 [Music] 1:07:22 much