The Nobel Prize in Physics 2001
Eric A. Cornell, Wolfgang Ketterle, Carl E. Wieman
I was born on March 26, 1951 in the small town of Corvallis, Oregon. A number of years earlier my newly wed parents N. Orr and Alison Wieman, like somewhat belated pioneers, had driven their decrepit car across the country to settle deep in the forests of the Oregon coastal range. My father began working in the lumber industry and during most of my childhood he worked as a sawyer in a sawmill. I was the fourth of five children. Most of my childhood was spent in the woods of Oregon where lumber was the sole industry. Probably some of my spirit of independence came from growing up far from other houses and towns. The nearest tiny store was always many miles away over unpaved mountain roads. Some of my earliest childhood memories are of the long school bus rides that my siblings and I used to take over those winding roads to go to school.
Much of my youth was spent wandering around in the forests of towering Douglas fir trees. I also spend much of my time reading and picking fruit and fir cones to earn spending money. Every Saturday my family would make a long expedition to the nearest town to do the week's worth of shopping. A stop at the public library was always part of these trips. Although I was unaware of it at the time, my parents must have made special arrangements for their children to use the library since we lived far outside the region it was supposed to serve. The librarians would also overlook the normal five-book limit and allow me to check out a large pile of books each week that I would then eagerly devour. That experience has left me with a profound appreciation for the value of public libraries. At the time I was quite envious that my friends had televisions while we did not, but in retrospect I am very grateful that I spent this time reading instead of watching TV.
I went to primary school (up to grade 6) at Kings Valley grade school. It was a tiny rural school that had expanded from one to three rooms shortly before I enrolled. For the seventh grade I had to take the much longer bus ride (almost interminable for an impatient 13 year old!) to the small town of Philomath. My young idealistic teachers in mathematics and science there had a significant influence on me. I particularly remember my science teacher, Ron Tobias, who was just starting his first teaching job. I am sure that Philomath 7th grade, with all its children of loggers and farm workers, for whom education was not a particularly high priority, must have been a very tough job for a young teacher. At times I could sense hints of his frustration. However Mr. Tobias did a great deal to kindle my interest in science with his enthusiasm and knowledge. I still remember his explanations (far better than any of the material from my college courses!) of the structures of atoms in the periodic table and how these structures determined the various chemical properties and molecular reactions.
After 7th grade my parents moved to Corvallis (home of Oregon State University) so that my siblings and I could both avoid the long bus rides and take advantage of the better school system offered by this "big city" of 25,000. It was a heady day for me when we moved into a house that had a central heating system instead of just a wood stove and had an actual paved street out front! Although I was never a very sociable child, Corvallis provided me with somewhat more comfortable companions. My intellectual interests and the liberal political attitudes of my parents were always somewhat at odds with the leanings most of my previous rural classmates, but I fit in better with the children of faculty at OSU. I became close friends with a very smart boy, Brook Firey, whose father Bill was a Professor of mathematics. One summer Bill gave Brook and I our own private course in geometry. It was a rewarding and eye-opening experience to get a glimpse of the richness of mathematics, even elementary geometry, as viewed by a true mathematician. And of course, at that age, I did not realize there was anything unusual about a University professor spending a few hours each day to provide personal instruction to two fourteen year olds.
Brook and I also spent many hours engrossed in all sorts of projects constructing and investigating things. I think that much of my talent and enjoyment at improvising solutions to experimental problems goes back to those homebuilt projects. In this regard my older brother Howard also inspired me; he was always tinkering with machines and building astonishingly elaborate toys for his younger siblings. Carrying out these individual projects also developed in me a good sense of self-reliance and a sense when a piece of improvised apparatus was likely (or unlikely) to be adequate. This sense is one that I often see missing in students whose education has been confined to formal instruction.
During high school I was a good student, but never quite at the top of the class. I mastered the material, but was usually a little too independent to do precisely what the teacher wanted, and so was never considered among the very best students. Usually the worse the teacher (at least according to me), the lower was my standing. Although always interested in science, my most memorable classes were in literature and writing. From 7th through 10th grade I was a passionate chess player, spending hours a day on it. I traveled all over Oregon and occasionally to nearby states to play in tournaments. I was highly ranked in the northwest US among my age group, but at the ripe old age of 16 decided to "retire" to spend my time in more productive activities. Those activities were studying and playing tennis.
My high school grades, although not outstanding, were good enough to get me accepted into MIT. From what I now know about college admissions, I suspect my admission was considerably helped by their being intrigued to have a student who had spent much of his life literally in the wilds of Oregon. My accomplishments as a competitive chess and tennis player may also have helped. Although it may seem surprising that a boy from the woods of Oregon would aspire to go to MIT, my family always had a strong interest in education. Both my parents graduated from college and had come from welleducated families. My grandfather Henry Wieman was a rather well known Professor of Theology at the University of Chicago. Out my four siblings there are two Ph.D.'s, including a successful nuclear physicist, as well as a high-level software engineer.
My tendency to intensely pursue a particular activity to the exclusion of everything else was and is one of my most notable strengths and weaknesses. After "retiring" from chess, my focus turned to tennis. That continued after I went to MIT, and I played intercollegiately my freshman year. I also learned to play squash rackets and took to it so naturally that I was quickly at the top of the freshman intercollegiate squash team. My squash career was notable in that I can claim to have lost to some of the best players in the country, including one future national champion. Unfortunately my rather fierce competitive drive exceeded my limited physical capacities, and after surviving several minor injuries caused by throwing myself into walls and such, by the end of my freshman year I had seriously damaged my right elbow from excessive practice at squash and tennis. After several unsuccessful treatments, I then switched to playing left handed, and by early in my second year of college was starting to again be competitive in both sports at the intercollegiate level. At that point I developed serious elbow problems in my left arm, and reluctantly came to the conclusion that at age 19, it was time for my second "retirement". It was only then I turned my full attention to physics.
As one might imagine, going from the woods of Oregon to MIT was quite a culture shock. I did not do particularly well in classes my freshman year, but I greatly enjoyed an informal freshman seminar on physics that I had with Professor Al Hill. He was a gruff but kindly old faculty member. Although I had a general interest in physics at least since seventh grade, particularly the behavior of light and atoms, I was not totally convinced when I started at MIT that I wanted to go into physics. However, after this seminar and its casual far ranging discussions about physics, Al Hill encouraged me and suggested that I should get involved in research. I discussed this with my freshman advisor who was Daniel Kleppner, and he took me on to work in his laboratory my first summer of college. This was a dramatic change from my employment the previous summer. Then, just out of high school, I had worked in the lumber mill, "pulling on the green chain". As the green lumber came out of the mill on a large conveyor chain, my job was to pull it off and stack it in the appropriate pile. This was an exhausting job that gave me a clear taste of what real labor was like. Every now and then when I am fed up with some aspect of my job as an academic, it is useful to reflect on that summer on the green chain to remind myself how well off I am compared to all those people who spend their lives doing real work.
I quickly became deeply engaged in research as an undergraduate and continued to work in Dan Kleppner's research group until I left for graduate school. I found this much more interesting and educational than taking courses, and quickly adopted a philosophy of taking as few courses as possible. Since I never did terribly well in most normal courses anyway, particularly ones that had exams, this worked out well. I was actually remarkably successful at avoiding courses, helped in large part by the events of the times. The last few weeks (and the dreaded final exams) of my freshman year were canceled because of massive protests over the Vietnam War, and during the following years there were many opportunities to participate in experiments in various sorts of alternatives to normal classes. I took full advantage of all of these alternatives, and their rather lax requirements and oversight. I also spent countless hours discussing physics with the graduate students and postdocs (notably Dave Pritchard) in Dan Kleppner's research group. My education as a physicist came largely from my work in Dan's lab and these interactions with him and his group. I also spent much time in physics discussions with an informal seminar group (the "physics family") run by Rai Weiss and Al Hill.
In spite of (or because of) this unorthodox education, I ended up far more enthusiastic about physics than most of my classmates, as well as having a much better grasp of many basic concepts such as quantum mechanics. Of course I was considerably weaker in the formal solving of problems, and I still have not learned much of the standard material of the undergraduate curriculum. However, when I needed to know some material, I was completely comfortable with going out and learning it myself in a way that I discovered was not typical for my classmates. My undergraduate experience has always left me deeply suspicious of the claims of those who say a student cannot become a physicist without being required to take courses covering a whole list of specific topics. I have had a pretty successful career in optics and atomic physics without having a course in either, for example. Some may argue that this could only work because I was an extraordinary student, and the more typical student must be required to take a formal curriculum with a large number of courses and exams. However, it might be noted that before obtaining this unusual "education" there was little to indicate that I was anything special as a physics student. So one could equally well argue that it was not me that was exceptional, but rather the education I received. Perhaps if far more students learned physics in the haphazard way that I did, many more of them might turn out as motivated and successful as I have been.
I did become extremely involved in research as an undergraduate. Through a chain of circumstances, helped out no doubt by my enthusiasm and willingness to put in long hours of work, I ended up with my own lab and my own experiment. This involved the construction and use of a tunable dye laser, which at that time was a very new and exciting device. This was the beginning of Kleppner's group moving into the use of lasers to study atomic physics. I spent my time blasting atoms with a dye laser tuned to the atomic resonance line and looking carefully at what happened. To a large extent much of my subsequent career has been variations on this basic theme. After spending many very late nights by myself taking data in the lab and showering every day at the athletic center after exercising, I started to wonder why I was paying all that money, of which I had little, to rent a dormitory room I almost never saw. So driven by my involvement in the research and a desire to save money, I actually moved into my lab. After about a half a year, living in the lab got pretty old, and so I moved into a normal apartment, but the story of my being so devoted to experimental physics that I actually lived in the lab has tended to follow me ever since.
My work with dye lasers made me aware of the exciting developments in narrowband dye lasers and their applications to atomic spectroscopy being done by Ted Hänsch. That, along with the far superior weather and more relaxed academic atmosphere, convinced me to move from MIT to Stanford for graduate school. At Stanford I resisted the natural temptation to immediately jump into laser spectroscopy again, and so I spent a year looking fairly carefully into all of the different faculty and research areas in the department. However, in the end I concluded that working on laser spectroscopy with Hänsch was the best option. I began working with his group as they were developing a very high power narrowband dye laser for exciting the 1S-2S transition in hydrogen. Ted was a new enthusiastic young professor, the technology and the experiment were new and exciting, and because of my previous background I was able to become thoroughly involved in the experiment almost immediately. It was a fun time, made more so by the fact that we soon observed the H 1S-2S transition and used it to measure the Lamb shift of the 1S state. For my thesis work I then went on to develop the technique of polarization spectroscopy and built the first single mode continuous wave dye laser at 480 nm to further improve the 1S Lamb shift measurement and greatly improve the determination of the 1S-2S isotope shift.
As I neared completion of my Ph.D., I became interested in the subject of parity violation in atoms. This was predicted by the theory of electroweak unification, but had not been seen. It seemed like the natural next step to my thesis work in that it was using precision spectroscopy of atoms to test fundamental physics. But rather than further test QED in atoms, which by then I was ready to accept as being confirmed as well as ever need be, the parity violation work was looking for new physics in atoms that went beyond QED and was far from certain. It offered the possibility of using atomic physics to do important elementary particle physics. I took a position as an assistant research scientist at University of Michigan to pursue these studies. I joined Bill Williams' ongoing experiment to measure this parity violation in atomic hydrogen using microwave spectroscopy. Shortly after I arrived at Michigan I found that the research scientist position I had taken was not the research faculty position that I had expected. It had all the disadvantages of a regular postdoc, but none of the advantages in that there was not sufficient research money in the grant to cover my salary, so that I had also had to teach, and I had to be responsible for much of the administration of the research group. However, I threw myself into the experiment and worked extremely hard, and my position was converted into a regular assistant professor position after a couple of years. Shortly after this I developed a somewhat different formulation for how to describe atomic parity violation experiments. This allowed me to see clearly how to compare the sensitivities of a large variety of different experimental approaches. At that same time I was also becoming increasingly disillusioned with the hydrogen experiment, and my new formulation made it clear to me that a quite different approach, using laser spectroscopy of cesium, would have a far better chance of success.
For a variety of reasons I chose to pursue the cesium experiment on my own, after first receiving assurances from the department chair that this was a suitable activity. Unfortunately, my abandoning of the hydrogen experiment to pursue my own atomic parity violation experiment lead to considerable friction with senior faculty and general strife within the department. As a young assistant professor naïve in departmental politics I was quite vulnerable, and had a difficult time during my subsequent years at Michigan. However, during that time, Sarah Gilbert and I were able to get funding from Research Corporation and then NSF and used it to thoroughly develop a novel experimental approach for measuring atomic PV in cesium. Sarah was a graduate student that I had met soon after I arrived at Michigan. We then worked intensively with graduate students Rich Watts and Charlie Noecker to implement this difficult experiment. By 1984 we had made sufficient progress to indicate the viability of our approach, and this attracted an offer of a faculty position at the University of Colorado in Boulder. I eagerly accepted the offer.
The year 1984 was a very active one for me. First, Sarah Gilbert completed her Ph.D., and I accepted the job at Colorado. In late August we then packed up the entire lab into the back of a rental truck along with all the personal furniture of the graduate students, and then Sarah, Rich, Charlie, Charlie's girlfriend, and I set out on a modern day pioneer caravan across the Great Plains to Boulder, Colorado. After quickly unpacking the truck, Sarah and I then left to fly out to Oregon for our wedding. We had been anticipating this since shortly after we met, but we had delayed until after Sarah finished her degree. We then returned to Boulder to start our new jobs and a new lab.
In the supportive environment of JILA and the Department of Physics in Boulder, along with lots of very hard work, the four of us, Sarah, Rich, Charlie, and myself, were able to make rapid progress and in less than a year completed our first measurement of parity violation in cesium. As with all my experiments, I had started out wildly optimistic as to the difficulty and time required for this experiment, and it was both a tremendous relief and a tremendous satisfaction when it succeeded. It was the best measurement of atomic parity violation at a time when this subject was being pursued by a number of notable atomic physics groups. Our result established both to myself and the rest of the world that I would have a career as research physicist; something that had sunk into considerable doubt during my seven years of meager accomplishments at Michigan. Shortly after the success of the PV experiment I was given tenure and promoted to Full Professor at Colorado. During the subsequent 15 years, my group has carried out two further generations of this long and difficulty experiment with ever improving accuracy.
I would be remiss if I failed to mention the tremendous benefits that I have gained in my career by having a wife who is a very talented and intelligent physicist (as well as being a wonderful person of course). Shortly after we arrived in Boulder, Sarah took a job at the NIST Boulder labs where she has worked ever since. We worked together on the PV experiments, and still collaborate on an occasional small project. Talking with Sarah about physics has always provided me with countless inspirations for new ideas, and has revealed critical flaws that I had overlooked in twice as many bad ideas. She also can understand and share in my obsession with the research and its occasional extraordinary demands. Finally, her ruthless editing has greatly improved the writing of nearly all of my papers. When we are not working, Sarah and I can usually be found running or hiking on the trails of the Boulder Mountain Parks. We can also occasionally (but not frequently enough) be found at our house on the central Oregon coast.
The development of the diode laser technology that was needed for the third generation of the parity violation experiment led to my involvement with laser cooling and trapping and ultimately BEC. Originally in about 1984 Rich Watts and I were simply looking for something fun and easy to do with the diode laser technology we had developed for the PV experiment, as a respite from the very long hard grind of that project. This resulted in our slowing atoms using lasers that were about 1% of the cost of what was used for previous work by Hall and Phillips. I then became increasingly interested in laser cooling and trapping. Initially my work on it focused largely on developing it as a useful technology for doing other atomic physics, but then I became more involved in studying the novel behavior of atoms at the unprecedented temperatures we could achieve. In the process of those studies I worked with an undergraduate Bill Swann to invent the vapor-cell MOT to replace the traditional atomic beam loading of optical traps. This provided a means to trap atoms using only inexpensive diode lasers and a small glass cell, which was a dramatic advance towards making laser trapping a simple and widely useable technology.
To me personally, this reduction in the cost and complication offered the opportunity to explore a variety of speculative directions involving laser cooled atoms with relatively little risk, since the cost and effort was now quite modest. One such quick experiment was to switch the laser cooled and trapped atoms to a magnetic trap in order to avoid the limits we had discovered were imposed by the photons in the optical trap. This worked so easily and so well - we obtained trapped atoms about 100 times colder than had been achieved previously, with a corresponding enhancement in phase space density - that it inspired me to pursue goals grander than just better trapping and cooling technology; namely, the attainment of BEC by further cooling in the magnetic trap. Fortunately Eric Cornell joined me at just that time (1990) to pursue the goal of BEC. Ours turned out to be an extraordinarily friendly and effective partnership that has continued up to the present. Our pursuit of BEC is now well-documented history.
Over the past several years I have become increasingly involved with trying to improve undergraduate physics education and have been balancing my time between that and my research. I have been examining alternative curricula and learning about the research in physics education as to how students do and do not learn. A particular concern has been improving how physics is taught to students who are not planning to become physicists, in the hope of one day making physics understandable, useful, and interesting to a large fraction of the population. My efforts have ranged from working with national organizations pursuing widespread change in undergraduate physics education to developing useful innovations in the individual courses that I teach. Because of my particular concerns, these courses have lately been large introductory courses primarily for nonscience students.
From Les Prix Nobel. The Nobel Prizes 2001, Editor Tore Frängsmyr, [Nobel Foundation], Stockholm, 2002
This autobiography/biography was written at the time of the award and later published in the book series Les Prix Nobel/Nobel Lectures. The information is sometimes updated with an addendum submitted by the Laureate.
Copyright © The Nobel Foundation 2001