Princeton Alumni Weekly. May 19, 1961.

Lyman Spitzer (above, left) is Charles A. young Professor of Astronomy, Chairman of the Department, and Director of the Plasma Physics Laboratory; the latter was formerly known as Project Matterhorn, Princeton’s $35,000,000 attempt to harness thermonuclear energy for peaceful purposes. – Editor (1961)

Ideas of all sorts transcend national boundaries. It is impossible to confine an idea with any political subdivision. Now the rate at which ideas diffuse from one group of men to another depends very much on the intellectual area in which this idea is located. Cultural, philosophical, and religious ideas sometimes take many years, sometimes even centuries, to spread fully and to be comprehended by the peoples of the world. The reasons for this are many, partly because such ideas are difficult to understand without a long common tradition.

In the realm of natural sciences, however, the reverse is the case. Science may seem very complicated to those who have not had the specialized training that is required, but one of the features of science is that men anywhere in the world who have taken or have given themselves the few years of training that is needed can understand without difficulty scientific ideas originating anywhere in the world. Moreover, science has a very simple criterion for judging the accuracy, the correctness, the truth of any idea. Hence the validity of a new idea is easily tested, and scientists in one country can readily judge the validity of an idea advanced anywhere else in the world. For this reason the growth of science has been an international phenomenon, and new ideas and new theories in one part of the world are immediately understood, evaluated and utilized by scientists in all other parts of the world.

Princeton University, as one of the great world centers of the intellect, has played an important role in the international development of science. I would like to give today two specific examples to indicate the type of international collaboration which is inherent in science, and in which Princeton has played an appreciable role.

The Collaborative Enterprise

There are two specific ways in which a university can take part in this international development of scientific knowledge, which today forms so central a part of our culture. These two methods are, first of all, collaboration in the basic research which gives rise to science. The scientists in a university spend much of their time in developing new ideas, in testing them against observations, in obtaining observations, and in communicating their results to other scientists in this country and abroad. This research activity is a type of spontaneous collaboration with scientists everywhere in the world. It does not need to be organized, there is usually little need to set up international programs for this or that. Each scientist working individually who communicates his results to scientists elsewhere forms a spontaneous member of this vast international collaborative enterprise that we call science. And that is the first way in which a university can take part in the development of international science.

The second way in which a university can take part in the development of science is through the educational process. It is obvious, of course, that education is one of the central functions of the university, education and research together being the two major functions. Education of scientists from abroad forms a very central part of the work here at Princeton.

I should like to give in just a few minutes two specific examples in each of these fields – examples drawn from my own experience, simply because that is what I am familiar with. I believe these examples are typical of the other scientific disciplines that have been developed here at Princeton. In the realm of research, I shall use as an example a particularly fascinating astronomical research problem of the last few decades, to provide an indication of the specific way in which scientific ideas develop by the interplay of work all over the world. To understand this example, I must say a little bit about astronomy. I am always a little hesitant in talking to a non-scientific group about astronomy, because I am always reminded of a story that came out in the New Yorker a number of years ago. This was a brief account of a young boy who was asking his mother some questions about the planets and the stars. The boy’s father, who was away at work, was an astronomer, and the boy’s mother said, “Well, Willie, I have a little trouble answering all these questions. Why don’t you wait until you Daddy comes home tonight and he’ll tell you all about the stars.” “Oh, Mommy,” said the little boy, “nobody wants to know that much about them!”

The particular area of astronomical research which I shall use for an example this morning is in the field of interstellar matter. We have learned during the last twenty years that there are vast clouds of gas and dust floating between the stars. These clouds are so enormous that it takes a ray of light, traveling 186,000 miles every second, several years to cross from one side of a cloud to another. The development of our knowledge of these clouds, and more particularly the understanding of how they interact with each other and how they condense to form new stars that were not there a few million years before (and a million years is a short time to an astronomer, you understand) – the development of this knowledge is a very good example of how international scientific collaboration arises spontaneously between scientists in different countries. It is also a very good example of collaboration between observational astronomers who have obtained their observations at the great telescopes on the West Coast of this continent and most particularly at the hundred-inch telescope just outside Pasadena, and between theoretical astronomers all over the world who interpret observations obtained with these giant telescopes.

A number of dates serve as milestones in the development of our knowledge on these interstellar clouds. One milestone, for example, was in 1926 when the great British astronomer, Sir Arthur Eddington, working at Cambridge University, put together observations obtained by German, Canadian, and United States astronomers over the previous ten to fifteen years, and showed for the first time there must be a gas permeating all of interstellar space. With a brilliant theoretical analysis he was able to make sense out of these different observations published by these other astronomers, and he showed that there must be interstellar material between the stars.

Next Milestone: 1965?

A second milestone about ten years later, in 1938, came when an equally celebrated, equally capable Russian astronomer, whose name is Ambartsumian, took the data obtained primarily by American astronomers with the hundred-inch telescope, together with previous theoretical work, and showed that this interstellar matter was not uniform but must be concentrated in certain clouds, each many trillions of miles across.

Another milestone came in the next five to ten years in the period between 1940 and 1950, when a group of us from Princeton went to Mt. Wilson, used the great telescope there and by interpreting these observations, in collaboration with astronomers in other universities, were able to unravel what the physical conditions were in these interstellar clouds. We were able to answer the questions, “How hot are these clouds? How much material is there?” In this work a Danish astronomer who was director of the University at the Royal Observatory at Copenhagen played a central part.

Another milestone was in 1953 when Fred Hoyle, a celebrated British astronomer whose popular books some of you may have seen, was a visiting professor here at Princeton, right across the way here at the Observatory. He showed theoretically that these clouds could condense into new stars similar in their properties to the sun.

A fifth milestone which is some distance in the future, and here perhaps I am being hopeful, is in 1965, when a telescope will, we hope, be launched into orbit by the National Space Agency, for use by the Princeton group. One of the main functions of this telescope will be to analyze the properties of these interstellar clouds and to obtain more information on how they condense into stars and thus to be able to complete this important chapter in the origin and life history of our universe.

Let me pass on from this discussion of astronomy and international collaboration on the spontaneous level to a brief description from another field, that of plasma physics, where the university, with the support of the Atomic Energy Commission, has undertaken a small but important program of education for scientists of other countries. You may not be entirely familiar with the work of the Plasma Physics Laboratory. I may say that the goal of the laboratory, formerly Project Matterhorn, is to develop a power source based on atomic energy in hydrogen. Since hydrogen is available in plenty in the oceans of the world, this program if successful would provide an almost infinite source of power that could last for many hundreds of millions of years. Because of the importance of this work to nations everywhere, countries all over the world are beginning to take active interest in this field and are beginning to undertake research programs in this area. To carry out this research, to tap this power in a controlled manner, one must make progress in a completely new field of physics that we call plasma physics. I do not wish to go into the details of plasma physics, but this subject involves an investigation of the properties of a very hot gas under rather unusual conditions. Princeton is in a very central, almost unique position in this area. There are many major research efforts in controlled fusion in plasma physics, but the only major research effort which is at a university, which is unconnected with any classified work on hydrogen bombs or nuclear weapons of any sort, is that here at Princeton. For that reason we have a unique responsibility to train scientists from other parts of the world in the methods and techniques that have been developed in this field.

Several years ago, in fact immediately after this work was declassified, we set up a number of post-doctoral positions. We had to limit ourselves to five men every year because the laboratory couldn’t accommodate any more. The theory of these positions is that scientists would come here and learn by doing, by taking part in our research program. There has been a very active response to this program. In two years we’ve had 37 applicants from 17 foreign countries, 10 in Europe, 6 in Asia and Australia. We have been able to only admit 5 every year, as I say, but these scientists have come here, have worked closely with our group and have made an important contribution to the work of our laboratory. They then go back to their own countries, where they play active parts in the development of similar programs in plasma physics. This program has been one of the many ways in which Princeton has contributed to the education of scientists all over the world.

This was originally published in the May 19, 1961 issue of PAW.