John Wheeler - Session XIII - XXII

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Interviewed by
Kenneth W. Ford
Interview dates
October 5, 1994 - April 12, 1995
Jadwin Hall, Princeton University
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Interview of John Wheeler by Kenneth W.

Ford on 1994 October 5 - 1995 April 12, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA,…

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This is the last ten sessions of oral history interviews with John Archibald Wheeler conducted by Kenneth W. Ford between December 6, 1993 and May 18, 1995. They represent research material for Wheeler’s autobiography, Geons, Black Holes, and Quantum Foam: A Life in Physics (Norton, 1998).


Harry Smyth Foresees War Work
(for Chapter 1)

Harry Smyth sat me down with him at a lab bench one day in the fall of 1941 and referred to Milt White and to other lab members who had been drawn off to do war work. He referred to the work that he knew I was doing with Feynman. "You better finish it up soon," he warned, "because surely soon you will be involved in war work, too." And soon I was.

Working with Bohr
for Chapter 1)

We started in my office with Bohr sitting or standing near the blackboard and dictating a broad picture of how nuclear reactions must go as envisaged by his compound-nucleus model, and then turned to what that model has to say about this new reaction of fission. To fill out that picture in the case of fission, however, we had to clear up a host of details. These we would discuss, taking turns drawing diagrams on the board and raising questions that we set off to clear up by calculation, then discussing with selected colleagues puzzling points of principles.

An Institute for Advanced Study colleague in mathematics, Marston Morse, had worked out the theorem, famous in the Princeton community, that dealt with the nature of a landscape. With so many peaks and so many valleys, it must have so many mountain passes. One such mountain pass must symbolize the energy hill that the wiggling nucleus must surmount if it is to undergo fission. But what is the probability that the nucleus will use its energy resources to surmount this barrier? This question seemed to me no different in nature than the analogous question about the probability for a complex molecule to split. My older colleague, Eugene Wigner, had, I knew, worked with the physical chemist Michael Polanyi of the Kaiser Wilhelm Institute. Wigner had eaten some contaminated oysters a few weeks before and was in the university infirmary with jaundice. Despite his yellowed face, he greeted me warmly, listened to my question, and steered me in the right line of thinking. Soon I could try out on Bohr the formula I derived for fission probability as proportional to what would nowadays be called the "number of channels" that lead over the barrier to fission. Only in later years did experimentalists achieve the accuracy needed to reveal the opening up of a new channel as the bombarding energy was raised to the appropriate level.

At that time, I occupied Room 214 in Fine Hall. Wigner occupied the corner office in Fine Hall that had been Einstein's (Einstein and other Institute people had recently moved to the Institute's new quarters away from the campus). Bohr was assigned an office next to Wigner's for the period of his visit. Between his office and mine were the tea room and several other offices.

Sometimes we would work in my room, sometimes in Bohr's. More than once had the stick of chalk broken in two as Bohr leaned on it to emphasize his point. As we left that room to go to tea, he would lift the rug and kick the fragments of chalk under it to hide them from the janitor who, proud of the building, and oblivious to the eminence of its occupant, would scold Bohr for messing up that beautiful place. And always in the left hand corner of the blackboard in his room would be a list of the things he had to do, the outside obligations he had to meet.

The drawings I made to illustrate the paper did not have the quality of any professional draftsman, but I had absorbed enough from my course in engineering drawing [at Hopkins] to enjoy doing them. There were still things to be done on the paper when Bohr left. Peierls and Weisskopf told me they envied my having his permission to send in the paper myself without all of the usual last-minute Bohr changes.

Sometimes as Bohr entered my office, he would find me with Ray Bowers, the architect and contractor for the house that Janette and I were having built. In what different worlds the two men lived!

Archibald (Archie) Blake
(for Chapter 3)

Archibald Blake was a first cousin, the son of my mother's sister. He gave me Pierce's Table of Integrals as a gift. I still have it. He was only about four years older than I. He lived in Chicago and visited from time to time. His older sister Mabel stayed with our family in Youngstown when she was recovering from an unhappy love affair.

John W. Reid
(for Chapter 3, page 3)

John W. Reid was a great uncle, the brother of Grandmother Archibald. He often came to Sunday dinner with us during the year we spent in Washington, DC. At these dinners, we had debates on the war [World War I was then in progress]. Although in that war Japan was a US ally and helped take Pacific islands away from the Germans, Uncle John was deeply suspicious of the Japanese. He tried to make the case that everything they did was by virtue of copying the west. He liked to tell a probably apocryphal story of an automobile the Japanese had copied with a bent tailpipe so that all their new cars appeared with bent tailpipes. I can recall that our side of the family was skeptical of his position and his arguments. However, he was thoroughly respected in the family for we all knew that he had been part of Sherman's march from Atlanta to Savannah and from Savannah to the sea.

Other Washington Recollections
(for Chapter 3)

Our house was at 1105 Park Road. It is now destroyed, torn down to make room for stores. It was close to Rock Creek Park.

I'd like to remember the occasion for President Wilson speaking in front of the Lincoln Memorial, and the date. I heard that speech as a child, with my grandfather.

Grandfather also took me to a naval gun factory in Washington. It was off limits to the public, but he barged right in with me. When a guard tried to put him out, he responded with the story of his Civil War service, so I got to see how the inside of one cylindrical casting was made just a little smaller than the outside of a more central casting so it could only be made to fit by heating it, sliding it on, and then letting it shrink as it cooled, thus putting the outer steel under tension and the inner steel under compression.

There were usually debates at Sunday dinner. Once my grandfather got everyone else convinced of his position, he turned around and took the opposite position and started debating for it. I can't tell whether this was the start of my interest in debating in high-school days.

Gift from Slave to the Reids
(for Chapter 3, page 9)

The Reids in Ohio were given two silver spoons by an escaping slave after they nursed her back to health. She had taken just these two spoons when she escaped from her master and presented them in gratitude to the Reids. They are now with my sister-in-law, the widow of my brother Rob. She lives in Louisiana.

Rabbi Morris Lazaron (for Chapter 3, page 11)

We should add something on Morris Lazaron. I have written about him in my contribution to the Feynman issue of Physics Today. This piece can be found in Rigden's book Most of the Good Stuff.

Rabbi Lazaron once said to me "Now I know you think that Jews should have equal rights, but don't they sometimes rub you the wrong way?" I met him through our Baltimore federation of young people's groups. He may have initiated our meeting. He was smart enough to know that if you want to promote an idea, it is best to let other people think it is their idea. I was head of the Unitarian young people's group. It was an excellent way to meet a congenial group of other young people. I first met Janette there (after first meeting her sister Isabel).

The Cyanide Tank in Mexico
(for Chapter 4, page 5)

When the tank of cyanide was once drained, coat buttons were found in it. (The coats had been dissolved.)

Social Life at Hopkins (for Chapter 4, page 18)

At Hopkins, a group of graduate students from all across the campus (not just physics) had formed, interested in dances. Somehow I ended up as chairman of the group, and responsible for promoting the acquaintance of one with another.

I have a theory why so many people treat me in a friendly way. I am shortsighted and therefore late to recognize an acquaintance as we meet walking on the sidewalk. Therefore I adopted, from freshman days, the policy to try always to have a smile as if to greet an acquaintance. Some whom I did not know ended up that way as acquaintances. Perhaps that is why I became the chairman of the committee arranging dances for graduate students and introducing one to another at our get-togethers.

Some of the young ladies [who came to the dances] were students. Most came from the larger Baltimore community. I usually brought a girl with an exotic, attractive way of looking at things. One, a flame for a long time, was the daughter of Danish parents. Another was the daughter of French parents. Both were of about my age. They transformed Europe from a far-away abstraction to a world throbbing with attraction and passion.

More frequent encounters came from the regular Sunday evening meetings of the Young Peoples Group of the Baltimore Unitarian Church. Of these meetings I remember well the liveliness with which we took up current issues of the day. Generally we managed to get an older leader in his or her profession to introduce the topic and intervene from time to time in the headstrong discussion. Somehow I ended up as president of this young people's group. The girls who belonged gave it an attractive social flavor.

Isabel Hegner, like more than one of the other members, invited us to a social dance at her house.

One of the most attractive and provocative people we got [for discussion leader] at the Young People's Group] was Rabbi Morris S. Lazaron. Through contact with him, I ended up promoting the organization of a federation of the young people's groups of various churches and synagogues in Baltimore. I still remember a private interlude once with Rabbi Lazaron, where he asked if I did not have some antisemitic prejudice. Unlike so many Americans, I did not appear to have any such prejudice. I did not think to recite some of the long Wheeler and Archibald history of moving away from communities persecuting our religions, nor surviving the starvation months of the siege of Londonderry. But then he asked a harder question, "Aren't there some Jewish people whose very tone and way of action turns you off?" I cowardly said, "No." I did not at that moment call to mind an experience my father had when we still lived in Youngstown, Ohio. His zeal in pushing the library in one way or another upon every available occasion led someone to accuse him openly of being Jewish himself. Still to come lay that visit to Auschwitz that made one of the most moving experiences of my life.

Our Unitarian young people's group took its name from that scientist, discoverer of oxygen, and independent thinker Joseph Priestley, for his anti-

trinitarian preaching. He had been driven out of his home in England [I don't remember the details—was his house burned down?].

[What follows is suggested actual text to be used on page 4-183 Isabel Hegner, one of the members of the Joseph Priestley group, invited it and some of the larger community of friends to a dance at her house in the spring of 1933. There I fell under the fascination of [instead of "became intrigued with"] her older and still more vivacious sister Janette. Janette quickly discovered that I wasn't much of a dancer and suggested that we sit and talk. I learned that she was shortly to make a trip with her father to the American Southwest to view Indian ceremonials. [It is possible that this Southwestern trip was a year later, in the summer of 1934. KWF] I remember my problem as I sent her a postcard to southern California a couple of months later: how to translate the pronunciation into a spelling. She never reproached me in later life for having written "Genet."

Breit Anecdote
(for Chapter 5, page 5)

Breit once told me about a meeting that he had with Ehrenfest when he [Breit] was an NRC Fellow in Leiden. Ehrenfest had been doing all the speaking when suddenly he turned to Breit and said, "Breit, behaupten Sie etwas." [Breit, stick up for something.]

Working with Breit (for Chapter 5, page 7)

Breit was a heavy smoker, but there was no flack in those days about a smoke-free environment!

I recall a lunch at which we discussed the experiments of someone at NYU [maybe Crew?] that conflicted with the principle of CP invariance [or maybe just P invariance]. The consensus spoke against [the experimental result] as a theoretical impossibility, an assessment that left all four or us, I am afraid, uncomfortable. Had that result been taken seriously, physics would have jumped ahead x years.

Liquid Positronium
(for Chapter 5, page 18)

Later I calculated what properties can be expected for a system composed of very many positronium atoms held together by their mutual attraction. Liquid positronium is calculated to have a density about 1 /xxx that of water and to be a superconductor. The ease with which it might release its energy makes it far more dangerous than nitroglycerine to carry around in a can! Nevertheless, it makes a most interesting extreme form of matter to study. I hope that an observable amount of it will someday be condensed out of a gas that is heavily radiated and then suddenly expanded and supercooled. Drops of liquid positronium, the magic fluid of myth ...

Courtship of Janette
(for Chapter 5, page 19)

I sent flowers to Janette at Rye Country Day School on what by accident turned out to be Mother's day [May 1934]. The other teachers there really ribbed her about that.

X-Ray Absorption
(for Chapter 5, page 13)

A photon, or light quantum, that comes down the pike is going to have a difficult time getting itself absorbed by an atom, we [Bearden and I] had to recognize, when that photon gives these electrons of the atom an unfavorable energy—unfavorable because the natural state of that energy is already occupied by an electron. This blockage often comes about in an atom of large atomic number because such an atom has so many electrons that they fill the states where the upgraded electron would like to go. As a consequence, the heavy atom absorbs light less strongly than would otherwise be expected.

This is true for photon energy less than K shell binding. For energy greater than the K shell binding, there is no such inhibition. Combining all effects for an atomic electron, the transition from, say the tenth state, to the ground state, if it were to take place, would give the opposite of absorption. If you apply the sum rule to that one electron, the transitions upward giving absorption and downward giving emission, you find that the positive part (absorption) is more than unity since the downward part would be negative. The electron in the tenth state absorbs more strongly than otherwise expected. To sum up, the absorbing power that would have been contributed by transitions from the first to the tenth state is made up for by enhancement of transitions from the tenth state into the continuum.

Unpublished Wheeler-Plesset Paper
(for Chapter 5, page 24)

I don't know what Bohr had against the paper. We can just write that Plesset and I went back to work, but in the end the work was never published. It was sort of understood that I would refine it and get it into publishable shape, but it never got done. The work showed that, given the known absorption of photons in lead, the principle of causality limits how much scattering there can be. We used the Kramers-Kronig dispersion relation.

Role of Theory in Understanding Cosmic-Ray Observations
(for Chapter 5, page 25)

It took theory to understand what the observations were revealing. Were these penetrating particles electrons or atomic nuclei or known constituents of atomic nuclei: neutrons and protons? None of the three. It took theory to show they couldn't be electrons. Bohr and Williams gave the decisive argument against electrons. They avoided any direct appeal to the theory of high-energy electron processes, looking at the interaction of a fast electron with a block of lead, not in the frame of reference in which the block of lead is at rest, they emphasized, but in the frame of reference of the electron. The electric field of force of the lead nuclei that whiz by are indistinguishable in their effects on the electron, they pointed out, from the electric field of an equivalent beam of passing radiation, radiation consisting of photons of relatively low energies whose effect on electrons is well known both theoretically and experimentally. These equivalent photons so drastically affect the electron that it can never penetrate the six or ten inches of lead. So what comes through can't be electrons. Neither can it be any other then-known particle. This conclusion created the climate of opinion, the intellectual background, for Carl Anderson's discovery of the meson at Caltech in Pasadena in the fall of 1935(?).

Wedding and Honeymoon
(for Chapter 6, page 1)

The wedding was held early in the day, maybe at 10:00, so that my sister could get to an exam that she had later in the morning. It was in the Hegner's house.

Right after the ceremony, Janette and I climbed into the black Ford coupe, complete with rumble seat, that we had just purchased (used). We took off for Charlottesville, VA, where we visited the beautiful campus and library that Thomas Jefferson had designed for the University of Virginia. The next day we went to Chapel Hill, to meet our future colleagues and look for a house. My father and mother being in England, they had offered us the use of their house in the village of Benson, Vermont. After about two days in Chapel Hill, we drove the Ford to Vermont, and stayed there for the summer. (My parents were away for at least a month.)

This was Janette's first visit to Benson. She got as much amusement as I did from people keeping track of us. The telephone operator had her office up the street, and upon seeing the light go on in the house, she phoned us to see if all were well. Other people in the village kept tabs on us, too. (Let's ask Janette for her recollections.)

The kitchen stove was an all-day proposition. It was my job to start a fire in the morning and keep it going during the day, and not let it run out of firewood. While I was doing physics that summer, Janette was doing a lot of reading. There were so many interesting books around the house, history, biography, and English classics. Did we start our habit of reading aloud to each other that summer? I can't remember.

My sister Mary and brothers Joe and Rob were living at the Hillside Camp three miles away. (The family had built this camp.) None of them were married yet.

My father had been invited to a library meeting in Spain. That paid his way. Since it looked like he never again would have the chance to go to Europe, he wanted to make sure that my mother had the chance to visit, too. They decided to focus on England and Scotland, so rich in the scenes of the books they loved to read. His meeting in Spain ended just at the time I was returning from Copenhagen to the United States for my wedding. He knew the name of my ship, the Europa, and knew it was going to stop at Le Havre on its way from Hamburg (or Bremen?) to New York. I did not know he was going to try to make contact with me. But he sat up all night on the train through France and got to Le Havre in time to see my ship at anchor. He cajoled his way on board and, lo and behold, found me standing on the deck looking down on the shore.

A few days later, he was in England meeting my mother, who, from her own ship, had an exchange of radiotelegrams with me as our ships passed, out of sight, on their oppositely directed Atlantic crossings. No wonder that they could not be at our wedding.

Physics Department at UNC
(for Chapter 6, page 2)

I taught classical mechanics, quantum mechanics, and nuclear physics, some at the undergraduate level, some at the graduate level. (I can't remember what my teaching load was.) The graduate students were older than I. Their friendly North Carolina spirit was typified by Dudley Williams, who started in calling me Brother Wheeler instead of Professor Wheeler.

One of the graduate students, Katherine Way, undertook a thesis with me, a wonderful opportunity for me to learn more nuclear physics.

Frank Porter Graham was the President of the University of North Carolina, endowed with a warm, outgoing personality and animated by a vision of what the university can and should mean to the life of the state. He had brought in Arthur Ruark from xxx to bring zip and a more modern outlook to the physics department, even at some risk to egos in the town and in other departments, bruised by the no-nonsense push of this new department head.

Ruark and Harold Urey, while together at xxx, has written one of the exciting physics books of its time, Atoms, Molecules, and Quanta. I had been one of the lucky graduate students to learn much of his modern physics from a study of this book. Both authors were in love with their subject and communicated that feeling to thousands of lucky students around the country. Somebody went away with my copy of the book (my choice of prize in a debating contest) but I gave a gulp and shelled out my own money to get a second copy.

Otto Stulman, one of the old-line members of the dept, took away the mystery that crept into the neighbor's face when told, "I teach physics." Otto short-circuited the question and the word "physics" by saying, "I work on X rays" and by wearing a white coat. Earle Plyler taught general physics and had such a happy, joking way to deal with the problems of life that he was a general favorite. He died in 19xx, but I am happy to say that the American Physical Society regularly awards a prize in his honor (I don't remember the source of funding for this prize).

The Herd Instinct
(related to the discussion or research directions, Chapter 6, page 5)

Edward Teller once disdainfully defined an "intellectual" as someone who thinks the same things and uses the same words as other "intellectuals." If these words describe how much it alienates him (and me) to encounter a community imbued with a herd instinct, they may also excuse the fury we had to bottle up when colleague after respected colleague in nuclear physics spoke so assuredly of "nuclear forces" being obviously distinct from electromagnetic forces. "Fork up or shut up, "I had to say to myself. "Let me try to derive nuclear forces as a consequence of electromagnetic forces, nuclear particles as assemblages of positive and negative electrons." So motivated, and enchanted by Dirac's picture of the positive electron, or positron, as a hole in an infinite sea of negative electrons, I found myself more than once in my life working out the structure of assemblages of positive and negative electrons.

By now I'm afraid I can't die 100 percent happy until I see somebody producing droplets of liquid positronium. By sudden cooling of a gas irradiated with positrons (or gamma rays), it may be possible to achieve it.

Another mantra also irritated and stimulated me because of the unthinking herd instinct that seemed to me so often to lie behind it: "The force between two nucleons, alone or in the nucleus, arises from the exchange of mesons between the nucleons, as the electromagnetic force between two electrically charged particles arises from the exchange of photons between them." It is sad to look at villagers working away at curing tobacco for sale, much as one might like those individual villagers themselves. To unbelieving me, it is equally sad to see a community of bright and otherwise interesting young physicists working fervently away on one or another esoteric application or elaboration of the meson theory of nuclear forces. Fortunately, nobody tries to explain the chemical forces which attract molecules by the exchange of mythical chemons between molecules.

K: Did your distaste for the meson exchange theory of nuclear force date from Yukawa's first paper on the subject?

Yes, it did.

Living in Princeton During First Visit to the Institute
(for Chapter 6, page 7)

The head of the house where I rented a room treated his wife in such an abusive way that I think he felt called upon to excuse himself to me by saying, "That's the way my boss treats me. So I treat her the way my boss treats me. Otherwise I'd go crazy."

Neighbors in Princeton (for Chapter 6, page 10)

Next door [to our Battle Road house] on the west lived the art historian xxx Panofsky. [K. Insert footnote on his sons, the smart Panofsky and the dumb Panofsky.] Across the street were Carl and Janet Ten Broeck. Carl was Director of the Princeton division of the Rockefeller Institute for Medical Research. Through him we met Wendell Stanley, discoverer of a form of life with crystalline structure, the tobacco mosaic virus, [and also met] his wife and other live-wire members of a great research center.

Around the corner from us, on Battle Road Circle, I believe, lived Vladimir K. Zworykin, known, perhaps oversimplistically, as "the inventor of television" and his warm-hearted physician wife Katusha. Zworykin was a vice president of RCA and worked at the RCA Laboratories located about three miles from Princeton. He had been an emissary of the Russian government with responsibility for purchases involving large sums of money. At some point, he decided to stay in the United States. Zworykin told us that television was the most decisive invention of the 20th century.

Next door to Zworykin lived the Institute for Advanced Study's luminary in economics, Winfield Rieffler, and his wife Dorothy. Rieffler had ties with the administration of Franklin D. Roosevelt, and described to us his first-hand contact with the President's way to deal with economic problems. It is difficult today to remember how strongly people differed in those day in their views on economic matters, and how violently Roosevelt was attacked for his so-called "tax and spend" philosophy. Rieffler, during the war, served in England as a United States representative (perhaps a minister) helping allocate scarce resources to the most effective uses.

On the other side of Rieffler from Zworykin lived Hermann Weyl.

An appreciable gulf separated the academic communities of Princeton University and the Institute for Advanced Study on the one hand from the townspeople on the other. About a thousand commuted every day from Princeton to New York to legal or financial occupations.

Mary Wheeler became the wife of Eugene Wigner (after Wigner's first wife died in Madison, Wisconsin). I met her before that at a physics meeting. She taught physics at a women's college, perhaps Vassar. I approached her because she had the same name as my sister. I told her that I had a sister named Mary Wheeler who lived in Vermont. "Oh," she said, "I come from Vermont." "Where in Vermont?" I asked. "Fair Haven," she answered. That was the nearest town to the village where my sister lived!

[A few recollections of the Princeton community from more recent times] Next door to the house of Einstein on Mercer Street lived xxx Packard, the son of David Packard of Hewlett-Packard. He took an interest in the work and studies going on in the classics at Princeton and achieved what I considered a miracle, putting all of the known Greek and Roman literature on a single compact disc.

Through John von Neumann Janette and I came to know Abe Spanel, tycoon of Spandex. He lived in a beautiful place, Drumthwacket (?), now, I believe, the residence of the Governor of New Jersey. We also met von Neumann's daughter Marina, who was (and may still be) a vice president of General Motors.

Winding Down" at Hanford
(for Chapter 7, page 2)

Nobody who had been busy during the war was less than busy afterward, although with new goals.

I cannot recall any newspaper predictions about the end of the war in the summer of 1945. The news each day featured battles on land and on sea. Nevertheless, I felt that the war would be over by the time school began in the fall. So Janette and I decided we must get the children back by September to their long-term Princeton schools, however much longer I would need to stay with the plutonium project. That meant Janette having to take the three children on a long trip east. It would be best, we decided, if she and the children could re-enter normal life gradually by stopping off for a few weeks with her father and mother at Salisbury Cove, Maine, on Mt. Desert Island. The easiest course seemed to be to cross Canada by train. I took the four of them to Vancouver, B.C., to put them on the transcontinental train. As it pulled out and I made my own way out through the station to return to Richland, Washington, I encountered newsboys hawking extras, announcing "Atomic Bomb Dropped on Japan." Janette, too, with the children in the observation car of the train, found there copies of a newspaper and was elated at the successful outcome of our hectic past years. She looked around her at the nice-looking Canadians reading their copies of the paper, appalled that no one showed any sign of emotion. Finally, she could no longer contain herself and exclaimed, "Isn't it wonderful. The war will be over in a week or two." The others thought she was crazy.

No more news reached her until the train made a brief stop at Winnipeg. There she rushed out to buy a paper, but found no news except what the leaders of the various women's clubs of Winnipeg thought of the bomb. I got back to Richland too late to see the immediate reaction to the news.

End of the War in Japan
(for Chapter 7, page 2 - or elsewhere)

On more than one occasion, I have had a veteran of the Pacific war come up to me with thanks for saving his life, because he had been slated to take part in the intended invasion of Japan.

Not until 1962 did Janette and I visit Hiroshima and see the monument with those ambiguous words, "Let us not make the same mistake again." (I may be paraphrasing; I don't remember the exact words.) I came to know a Japanese physicist colleague who had permanently lost his head of hair as a result of his Hiroshima irradiation. Much more recently, in the 1990s, I attended a meeting in Tokyo sponsored by the Hitachi company. A kind executive picked me up at the Tokyo Airport in his car and took me to my hotel in downtown Tokyo, kindly sparing me a $140 taxi ride. He and his military comrades had been standing facing away from Nagasaki at the time that the blast from the August 10, 1945 explosion hit them and knocked them flat. They picked themselves up, undamaged, but found the transportation system so thoroughly knocked out that they could not go on their scheduled trip by train. He made his way back home by a two-day trip on foot.

Haru Hanamatsu (sp?) Reischauer, in a gripping book, Samurai and Silk, tells the story of distinguished family members, half of them in business, half in government. The last chapter focuses on one person who had been assigned to the Emperor's court in Tokyo. The cabinet of the Tojo government was generally unanimous in its decisions, so the Emperor's participation could be limited to a simple signature. Then came Hiroshima and much debate in the cabinet: Go on in the war? Surrender? Nevertheless, they brought to the Emperor a unanimous recommendation: Go on. He signed, but expressed his displeasure that the cabinet had delayed a whole day in letting him know the news of Hiroshima. Then came Nagasaki. This time there was no 24-hour delay. But the cabinet debate surfaced. At last the Emperor could make his own voice heard, and he insisted on surrender. The word of this decision became known in the nearby protective army garrison. They staged a coup, took over the Imperial compound, and cut, they thought, all wires connecting with the outside. However, they did not know that the Navy had installed a secret line. Through it, the Imperial party called in outside help. That force undid the coup and three of the ringleaders had to commit hara kiri. At last the Emperor could make his voice heard. However, he had never spoken to the Japanese people. The operator of a tape recorder was summoned. Inexperience, either his or the Emperor's, spoiled the first tape, so a second was made. The first was enclosed in a special lacquer box tied with the Imperial ribbon and taken by an honor guard to the radio station to be aired. The second, the good tape, someone carried along inconspicuously in his pocket so that another coup attempt would not stop the Emperor's voice from being heard. The message went out over the air, but in an antique Imperial court Japanese that only the higher-ups in the various communities could clearly grasp. "Wonderful, the war is over," exclaimed ordinary Japanese when the news percolated around the country: "But who won?" The idea had been propagated that the Americans were being allowed to come closer, bit by bit, so that it would be easier to defeat them. That chapter provides a quick answer to the familiar question, "But why did we have to drop the second bomb?" Fortunately, the third one did not have to be used.

The Move from Richland to Princeton
(for Chapter 7, page 2)

In returning from Richland to Princeton, it did not make sense to drive. Our ancient second-hand car would never have made it. We advertised. A fine-looking young man, a Mormon, appeared to buy it. He explained how all his previous purchases had been made with the advice of the Mormon church—in each case a piece of land which he had been told to hold, then after several years been told to divide and sell, in each case with substantial gain. We did not tell him that he should have consulted his church before buying our car!

Goods traveling to Europe in the Middle Ages had to pay toll, we are told, at almost every city. The belongings that we shipped back from Richland to Princeton included an embroidery coverlet made for us by my mother as a wedding gift. It never arrived—the toll for that transcontinental truck journey. I was back in Princeton for the opening of classes in September, 1945.

Cosmic-Ray Workspan>

(for Chapter 7)

Fermi was still in Richland when I left by train. He had an enduring fascination with the cosmic radiation: what those particles are, what energies they carry, how they acquire that energy, and what one could do with them. He must have seen more clearly than the rest of us that no national budget would admit expenditures big enough to produce the highest energies needed for understanding the structure of matter. It was natural for me to adopt this outlook and to get my Princeton colleagues to approve the conversion of Walker Bleakney's wartime shock-wave laboratory to a postwar cosmic-ray laboratory. (Bleakney put up no resistance. He went back to his pre-war love of mass spectrometry, which he could carry on in the physics building without the need of a special site.) I was the original director of the cosmic-ray laboratory. Thus began my experience seeking U.S. money for pure science.

How get personnel for this new line of work? Talk with anybody who looked bright-eyed and capable. There were few around immediately after the war, most of them aliens who had been out of the wartime research on grounds of citizenship. One I never did succeed in proselytizing because she, Chen Shiung Wu, and her husband, Luc Yuan (son of the first president of China), must have seen that they were destined to end up as distinguished members of the physics faculty at Columbia University. The Icelander Thorbjorn Sigurgeirsson brought to use on the cosmic-ray problem techniques that he had learned from nuclear physics work on the Princeton cyclotron. Put a particle counter above a pancake-sized piece of lead to detect the arrival of a cosmic-ray particle and put a battery of counters below the pancake to discover what, if anything, came out. In this way, Thorbjorn compared lead with other materials in their ability to stop the cosmic rays.

Another younger Princeton colleague from wartime days, W. Y. Chang, studied the radiation that came out when the cosmic-ray particle stops in the pancake: gamma radiation—radiation similar to X rays but made of photons of higher energy. Chang pursued vigorously the story of these energetic rays, which I always called "Chang radiation," although I never succeeded in selling the name. The source of the radiation turned out to be simple. The incoming particle, a meson, some 200 times heavier than the normal atomic electron, suffered none of the inhibitions that an electron would experience on entering a lead atom already provided with its normal full complement of electrons. A newly arrived electron would find no welcome among the orbits around the atomic nucleus, already occupied by electrons. The meson, on the contrary, cascades trippingly down the great staircase of energy levels feeding it to orbits closer and closer to the nucleus. The steps in this staircase of energy are, like the meson mass itself, some 200 times greater than the corresponding numbers for the electron, hence the energetic radiation. Won't the meson be snatched out of its orbit by the nucleus before it can get to the bottom of the stairs? Yes, it can and sometimes is.

A graduate student from Rio de Janeiro, Jayme Tiomno, saw a larger the new findings, an identity in the rate-determining factors in three apparently very different processes, proving once more my theorem as to why universities have students: to teach the professors. Undergrad? Graduate student? Postdoctoral? Junior? What does it matter!

Chang's wife we hardly ever saw. She was working with George Uhlenbeck at the University of Michigan. Husband and wife would occasionally meet in Indiana. (?) Some months after the end of the war, it became clear that China was gradually getting back on her feet. The two Changs felt that they ought to help their country and go back and give China the benefit of their experience. She ended up teaching physics in Beijing, he doing nuclear physics research, much of the time at the Soviet high-energy installation at Dubna near Moscow. Again they had to meet from time to time, but with the handicap of a far larger separation to overcome. He participated for a time in the Chinese nuclear weapons project, I have been told; but I cannot recall a single exchange with him on the subject of plutonium or explosive devices.

Ideas Underlying Particle Physics
(for Chapter 7)

On one of the side streets in Paris is a little shop that sells duplicates of various medals. What pleasure to look them over. I decided early on my favorite and have never changed, the medal from the Duke of Burgundy, le suis pressé" (I am in a hurry). Experimental physics gets answers, but theoretical physics often provides a quicker route to the result.

Particles and interactions between particles made up at this time the prevailing view as to how the world works. But how come either? My graduate days' acquaintance with the electron and its simplicities had encouraged me to believe longer than my more sensible colleagues that every particle could be built out of positive and negative electrons. Let the hard knocks come, I felt, and teach us the deeper truth about particles. Let us focus, meanwhile, on the more beautiful side of the story, the interactions —electric, magnetic, and gravitational—between particles. There grew up in time, to be sure, a litany that many a student was taught to repeat with a mindless faith of a catechism: there are four forces: the strong force, the weak force, the electric force, and the gravitational force. But my Protestant upbringing made me reject this catechism. What simpler faith could I put in its place? Ideals of unity and simplicity, unattainable now and perhaps for years to come. Take one force, electromagnetism, and explore and exploit it to the limit. That made a program pure enough and ambitious enough that I could give myself to it wholeheartedly.

The Collective Model
(for Chapter 7 late — Going to Europe in 1949)

I'm not sure I went to France with a draft paper on the collective model. My great push in France was to be on the theory of positive and negative electrons and what structures one could build from them. In my application for a Guggenheim, I had written of my plan to work with Bohr in Copenhagen on positive and negative electrons.

I didn't at first embrace the independent-particle model. I don't recall an early [1949] draft intended for Hill-Bohr-Wheeler co-authorship. The importance of the single particle model came, in my recollection, entirely from talking to Bohr [after I was in Europe in 1949]. We never got going on the positive and negative electron business that I had come for originally. I wonder how much he [Bohr] was a semi-permeable membrane that leaked information on the Aage Bohr-James Rainwater paper on nuclear deformations. Bohr and I were working on that subject when Harry Smyth called and urged me to come back to the United States.

I can recall later [1952?] working on the Hill-Wheeler paper to meet the deadline for the Annual Review of Nuclear Physics. We had a whole stack of figures. It was too much (and too late) for the poor devil of an editor. That's when we decided we should send it to the Physical Review. Sam Goudsmit got somebody at Physical Review to edit the manuscript, because it was really designed for a different outlet. This woman moved all the pictures to the end of the article, which took away some of the punch of the article that we had in mind. At the end, Goudsmit said we should send her a box of chocolates in appreciation for all the work she had done.

Gravitational Action at a Distance
(for Chapter 7 late - Going to Europe in 1949)

I don't know whether I mentioned in the Guggenheim application the idea of "sweeping away spacetime." Or did I consider it too speculative? It would be a nice way to start a paper to say: "I had been preaching that space is the whole show and what would I think of myself if I expounded a different outlook."

(mentioned in several chapters)

If the electron-positron idea didn't work out to build massive particles, at least it might serve to build polyelectrons. The three-particle entity was detected by Mills (?) at Bell Labs and published in Physical Review, maybe in the 1950s. I don't know that the four-particle entity [2e- + 2e+] has every been observed.

That dream stayed with me, so for Edward Teller's birthday celebration volume, edited by Hans Mark [date?], I did a paper on the equation of state of liquid positronium (or rather condensed positronium, either solid or liquid). In these last months, I was in touch with somebody who, in response to a question from me, held out some hope of someday condensing liquid positronium droplets out of a gas by sudden expansion. It continues to be fascinating that annihilation photons come from the space around more than one star. So the question arises whether that atmosphere is at all conducive to making liquid positronium.

(for Chapter 7, page 18)

Tiomno was of medium height, had a deep voice, was dark complected (tan, not black). He was antigovernment in the days when many thinking Brazilians were antigovernment. After going back to Brazil, he was dismissed from his position along with many like-minded colleagues in the government's self-defeating effort to change opinions. [There is something special about his wife and her political and emotional history that I cannot now remember. Tiomno was, I think, married when we worked together in Princeton.] He was inclined more to questions of principle than to questions of math formalism.

Robert Christy (for Chapter 8)

It was Bob Christy (of Caltech) who once declined to shake hands with Edward Teller at the Los Angeles Airport.

Cornelius Everett
(for Chapter 8)

Cornelius Everett walked down a corridor touching the wall as he went so he could think about mathematics, not about where he was going.

Rose Gonzalez and San Ildefonso
(for Chapter 8)

The traveler driving to Los Alamos from Albuquerque past Santa Fe branches off the Taos Road to the west and sees before him the mesa-studded profile of the hills (Jemez Mountains). Then he passes the Indian school. Then comes into view Black Mesa [we should consider putting in a picture of it]. The residents of the San Ildefonso Indian Pueblo below it took their stand on its summit against the Spanish troops sent in to put down the famous Indian insurrection of 17xx-xx. According to legend, the Indian defense collapsed when one of the Indian maidens revealed to a Spanish soldier the path from plain to summit.

The pots made by rival San Ildefonso potters, Rose and Maria, make the pueblo well known among collectors. Janette sought help with her intense Wednesday afternoon weekly cleaning and by some miracle ended up with Rose, her fame then unknown to Janette. We knew only that she was a grandmother gifted with the ability to speak Spanish, English, and her native Tewa. She became so attached to the children and the family that she invited us to take our last meal at her house down in the Pueblo shortly before our departure for the east. The living room where we ate was spare, neat, and clean. A substantial white refrigerator at the center of one wall counted as the major decorative element. We bought from her two large vases (pots) to serve as lamp bases. [We should ask Janette for other details. Did Rose give us a black plate as a gift? If we purchased it, what did it cost?]

"With what pattern should they be decorated? The thunderbird?" "Yes."

"A pine tree?"

"No, we never do that."

San Ildefonso Pueblo, like other pueblos of the Pueblo Indians, is divided into two clans, the squash clan and the turquoise clan. The colors designate the appearance of the men's bodies as they participate in the annual dances. At one point, San Ildefonso came into difficulty. The death of the Governor left the pueblo without the authority to sell hay and firewood to the outside world, their source of money under the standard US system of government-enforced communism. The two clans pushed rival candidates but found themselves unable to agree on either. Then xxx came into consideration. He, like a few other Pueblo members, had left the Pueblo for the Los Angeles area. There, thanks to the help of fellow Tewas, he got the financial support he needed to go the University of California and get a Ph.D. in nuclear physics. Now he was working at a good job at the Los Alamos Scientific Laboratory just up the hill from the Pueblo. A delegation from the Pueblo came up the hill and told him to give up his job to become Governor of the Pueblo. Later we saw him, along with the grandson of Rose, both bedaubed in the squash-clan color, dancing up and down as they took part in one of the annual Pueblo rituals. How sad to watch small Indian children, licking their ice cream cones, leaning against a wall and laughing at the spectacle before their eyes. What will be left of this centuries-old culture at the end of the coming century?

The Birth of Matterhorn
(for Chapter 8)

I could never figure out Norris Bradbury's reluctance to endorse Matterhorn. Shenstone was consulted. He was to bring it up with Oppenheimer to get his advice. Smyth was then full time in Washington, DC. Senator Jackson's right hand person, Dorothy Fosdick, is still around (perhaps in Washington). She might remember details of the creation of Matterhorn.

Later, Dorothy Fosdick asked me to chair a committee to make a recommendation on NATO science policy. It was a committee of about six or eight people. One was Reuben Mettler. (His electronics company has a branch near Hightstown.


March 1995 through May 1995
Collectively called "Tape 24"
Meadow Lakes

Newcomb-work other than Mercury's orbit
(related to Chapter 9, page 4)
Langley-work on aircraft and bolometer
(related to Planck work on black-body spectrum)

Simon Newcomb (1835-1909), who was mainly responsible for getting accurately the rate of precession of Mercury's orbit, was asked to do a National Academy report on Langley's experiments with unmanned flight. Langley was head of the Smithsonian and made numerous unsuccessful flights over the Potomac. The crashes were all too evident to members of Congress. Newcomb concluded that manned heavier-than-air flight was not possible.

The Wright brothers came to Washington and got some of Langley's lift and drag measurements, which they used in their design of an airplane.

Langley (1834-1906), upon becoming head of the Smithsonian, decided that in a country so vast as the United States, with its variable weather, one needed to study the sun more accurately. He invented a bolometer, which was subsequently used by Rubin (sp?) in Germany to measure the spectrum of cavity radiation. When Planck developed his black-body formula, he put it in a pneumatic tube in Berlin and sent it to Rubin asking him to seek to verify the formula with additional measurements. So American "know-how" played a role in the birth of the quantum theory.

Re Langley, see Britannica article on him. It cites his main interest in the sun. See also Newcomb article in the Britannica.

Ed Taylor and Spacetime Physics
(for Chapter 9, page 6)

Ed Taylor was at Princeton on a sabbatical (from Williams College?)) and sat in on an undergraduate course that I was teaching. Taylor took notes and they became the basis of Spacetime Physics.

Roald Sagdeev
(for Chapter 9, page 10)

Now Roald has literally embraced the west by marrying Susan Eisenhower, the granddaughter of President Dwight Eisenhower.

Geon as Transitional State to Black Hole
(for Chapter 9, page 12)

The waves in a stormy ocean sometimes come together to give a momentary wave of exceptional height. 172 feet is the highest of which I find any record. Likewise, gravitational waves arising from the battles of matter and energy in the early universe will occasionally coalesce. The resulting geon-like concentration of gravitational wave energy, if conditions are right, will, unlike the towering ocean wave, collapse to a black hole: "mass without matter," Daniel Holz, Warner Miller, Masami Wakano, and I showed in 1993.

Dark Matter, or Missing Mass (for Chapter 9, page 12 et seq.)

Three lines of evidence today argue that the bulk of the mass of the universe sits "out there" in invisible form. We do not know how much, if any, of this "missing mass" resides in the form of gravitational geons that have collapsed into black holes. Nor how much resides in black holes of any kind. The "machos" (massive compact halo objects) identified in gravitational lensing may be candidates for black holes.

1994, however, saw the discovery of a handful of dark objects with mass enough to deflect light. The idea for this discovery came from Bohdan Paczynski, a forty (?)-year-old astronomer who divides his time between the Princeton Institute for Advanced Study and the Warsaw Astronomical Observatory (?). In a 19xx paper, he suggested a way to detect dark objects that have mass enough to bend light. Look night after night at the same million stars of some nearby galaxy. When a gravitating object crosses the line of sight to the distant star, the rays of light will be bent and the distant star will suffer magnification by "gravitational lensing." This enterprise needs no enormous telescope. The Warsaw group of xxx (who?), Paczynski's old colleagues, had two telescopes that would blush to be next to California Mt. Palomar's 200- inch-diameter mirror, for their diameters were only xxx and xxx inches. They were quite large enough to distinguish clearly between the million stars observed in the xxx galaxy; and the light recording by CCDs (charge coupled devices) was efficient enough to make reliable records night after night of the same old stars. It's almost as if I, looking down from Mt. Wilson on the glittering lights of Pasadena, kept watch for any blinking off as a signal that a night-flying bird had passed between the street light and me. Only in this case, the object signaled its presence by an intensity blip due to gravitational lensing rather than a dip due to obscuration. The intensity rise (insert a figure?) lasted several nights, giving confidence of something real. But what? Not an ordinary star, because it would have shown itself. Not a cloud of absorptive gas, because it could not have raised the intensity. Not a planet, because the planet Venus, when it interposes itself every xxx years between us and the sun, cuts the sun's illumination of the earth by an amount too small to be perceived by any but the most delicate instruments. No wonder the responsible objects received the name machos (massive compact halo objects). The mystery that they enshroud makes one of the many attractions that draw bright young people to astrophysics today.

Evidence for missing mass: (1) The outlying stars in many a galaxy go around their galactic center at a rate faster than the attraction of the visible galactic mass can explain. The observations require that the extra mass be spread throughout the galaxy. See page 237 of A Journey Into Gravity and Spacetime. See also page 240. (2) Physics biases telescopes against seeing any matter at all in great regions of space where matter has a density a little lower than elsewhere. There, matter does not assemble itself into stars and therefore does not make itself visible. In this way one has been able to understand the spectacular 1986 finding of Valerie de Lapparent, Margaret Geller, and John Huchra: Great voids and great filaments in the distribution of the galaxies. (See figure on p. 239 of A Journey . . . Note also the recent work of Chung-Pei Ma of Caltech.) (3) "Peculiar" velocities of clusters of galaxies. (The Great Attractor.)

Origin of the Wormhole Idea
(for Chapter 9, page 14)

The wormhole idea actually goes back to Hermann Weyl in the 1920s. (See the chapter on Weyl in At Home in the Universe, especially pp. 176-77.)

Effect of Quantum Fluctuations
(for Chapter 9, page 15)

The electron, zooming around the proton in the hydrogen atom, responds not only to the electric attraction of the proton but also to the fluctuations in the electric field that affect all space. Hans Kramers, a former student of Niels Bohr, first fully realized this point and pointed the way to modern quantum electrodynamics, perhaps the greatest advance in physical understanding in the immediate post-WW-II years. (Kramers work was reported at the time of the Shelter Island Conference see Schweber's book.)

Fortunately, Willis Lamb and xxx Retherford of Columbia University, taking advantage of the microwave technology that had come out of the wartime development of radar, had just measured the energy levels of the electron in the hydrogen atom with unprecedented accuracy and found that they were incompatible with a force on the electron originating solely in the nucleus. Did the fluctuations explain the discrepancy? Inspired by the 19xx Shelter Island, New York conference where these ideas were discussed, Hans Bethe of Cornell made a first calculation on the homeward bound train that suggested that the Lamb-Retherford corrections to the energy levels of the hydrogen atom indeed result from fluctuations in the electric field pervading space all the time and everywhere. Julian Schwinger and Richard Feynman quickly developed two very different improved mathematical methods to evaluate the energy-level shift to be expected, and Freeman Dyson brought happiness when he proved the deep-lying equivalence of the two apparently very different ways of doing physics, a development in the history of science that makes the centerpiece of a book by Silvan Schweber, QED and the Men Who Made It: Dyson, Feynman, Schwinger, and Tomonaga.

Does this work prove or disprove the existence of wormholes? Neither. The wormhole idea so far has only this payoff—that it provokes our imagination.

Jadwin Hall, Princeton

Max Planck - and Use of the American-Invented Bolometer
by Rubens to Measure the Intensity of Cavity Radiation
(for Chapter 9, page 18—or to open Chapter 11 on quantum topics)

Regret assails me that I never saw or met Max Planck, who had announced the quantum in 1900.

Speaking in January in Munich (in impromptu remarks honoring Planck), I said that I would say something "nationalistic." Samuel Langley had been appointed in 1887 as Director of the Smithsonian Institution, successor to Joseph Henry (?), who was called from Princeton in the time of Abraham Lincoln to be the first director of what was to be in effect America's National Science Foundation. Realizing that the United States is a country of continental stretch, Langley felt that the Smithsonian could contribute to the new country in no way more effectively than by understanding the weather that ruled crops and animals. Accordingly, he encouraged colleagues to measure the amount of sunlight falling on the earth at many a location between one ocean and the other. Mountains were climbed to get above the clouds. That precaution served adequately for visible radiation, but what about the radiation in the infrared and ultraviolet that escapes detection by the human eye? To capture the important one of those two energy-carrying radiations, the infrared, Langley developed and made successive improvements in an instrument called a bolometer, from the Greek bole.

Word of this instrument reached far. Max Planck in Berlin wanted to understand the most fundamental feature of the physical world that he could lay his hands on. He knew that the amount and the quality of the heat radiation associated with a hot opaque surface depends not at all on the shape of the surface or the material of which it is made but only on its temperature, provided only that the surface bends up into the shape of a box or cavity. Here nature presented mankind with something new and wonderful and beautiful. The cavity acquired the name of a black body. Thus to look into it through a tiny hole resembled looking into a giant cave through a little opening. The cave would present blackness and so would the cavity. But heat the walls of the cavity and find that the radiation coming out with arty given color has an intensity that depends only on the size of the opening and the temperature of the wall.

What rules this black-body radiation, Planck asked himself. The intensity of light of any chosen color did not rise in proportion to the absolute temperature as the physics of the time had predicted. It came closer to doing so, however, the lower the vibration frequency of the radiation, or the longer its wavelength (the redder its color). What about the infrared? That is what Langley had studied with his bolometer, and that is what Planck's Berlin colleague xxx Rubens proceeded to investigate with a new bolometer aimed not at the sun but at the hole in a black-body cavity. Rubens brought his results around to the house one Sunday afternoon where Planck and his wife were having tea. Later, after Rubens had gone, Planck set to work to find a mathematical formula that would fit these new results along with the old results for light of everyday colors.

The single word "unfreezing" captures the essence of the new findings. The intensity of infrared radiation rose in proportion to the temperature when the temperature climbed high enough; but lower temperatures were not enough to drive the radiation to the level of previous predictions. In other words, it took a certain temperature to unfreeze the radiation-producing mechanism in the walls of the cavity. Moreover, this temperature required to drive the radiation-producing mechanism in the walls of the cavity up to 90 percent of the classically predicted output proved directly proportional to the frequency. No wonder this unfreezing effect had not been observed before. Visible light has so high a vibration frequency that the temperature needed to unfreeze it to 90 percent exceeded the melting point of any available substance. Planck had to conclude that light of a given color comes off the radiating surface, not with any arbitrarily adjustable energy but in "hunks," always of the same size for light of a given color, but hunks bigger in size for visible light of high vibration frequency than for infrared light of lower vibration frequency. I use the word "hunk" to convey the flavor of Planck's actual word, "quantum." In the food rationing enforced in Germany during World War I, the citizen got his quantum of bread, sometimes his quantum of butter, and rarely a quantum of meat. Hence what Planck called the quantum theory of radiation we might more appropriately call the hunk theory of radiation.

The formula with which Planck fitted Rubens' measurements did not yet convey to Planck the unfreezing concept and the idea that radiative energy comes in hunks. That took time and thought. But the same night Planck wrote a note to Rubens enclosing the formula and put it into the pneumatic tube mail that conveyed mail in those days with great speed from one part of Berlin to another. Not until December 8 (?) 1900 did Planck publish the formula and the unfreezing concept as it applies to the radiation in a black-body cavity. Albert Einstein, working in Berne, Switzerland in 1905, used Planck's hunk theory of radiation to explain a hitherto mysterious result of Heinrich Hertz. Hertz studied the photoelectric effect, the ejection of an electron from a metal surface when light hits the surface. Red light? No. Violet light? Yes. How come? The vibration frequency of the violet light is roughly twice as great as that for the red light. Hence the "hunks" of radiative energy are bigger. Hence they provide enough energy to extract the electron from the metal surface, as the red ones don't.

Length Scales
(for Chapter 9, page 18 bottom)

Suggestion: Expand on idea of fundamental and non-fundamental length scales.

Peter Putnam
(for Chapter 9, page 27)

Peter Putnam came from a wealthy Cleveland family. His brother had served as an aviator in World War II and had been killed in action. Not long after, his father had died. Thus Peter's affection became fixated on his mother, a powerful Cleveland businesswoman. It was a love-hate relationship. Peter inherited much of the family drive and know-how, as well as its love for art. When it looked as if a Cleveland election might go in a way not desired by the family, Peter took the initiative in getting posters designed and put up in all the Cleveland street railway cars.

At Princeton, the A.B. senior thesis is required of all students and is regarded by many in later life as their most important single educational experience. Peter's was a confusing mix of physics and philosophy. I could not see any rational way to assign it a grade and neither could the colleague who shared the marking responsibility with me. Finally we decided to give it a mark in the same ratio to the average of the marks of all other senior theses in physics as Peter's physics course work bore to their physics course work.

In accordance with family tradition, Peter was destined for the law, and went for two years to Yale Law School (the same Yale University Law School where my granddaughter Francis Ruml was graduated in 19xx). Ticking away inside Peter was a time bomb. He had read Sir Arthur Stanley Eddington's book, The Nature of the Physical World, and had acquired Eddington's belief that all the laws of the physical world can be deduced by pure reasoning. Perhaps once a year he dropped by my office and I tried unsuccessfully to disabuse him of this Pied Piper of a dream.

Finally Peter dropped out of law school and took a job with a fledgling electronics firm in New Hampshire—not full-time, but enough days per week so that the income would hold body and soul together. Despite the family wealth, Peter remained fiercely independent. His mother presented him with a Cadillac, but he made her take it back. I have known others filled with a sense of guilt at being still alive when a brother was killed in the service of the country, but I don't know how to analyze the thoughts and emotions churning around inside the troubled mind.

Anyhow, Peter followed my suggestion that he say good bye to Eddington and get back to something timely and tractable in the world of physics. As I was going to Leiden, he did me the honor of suggesting that he might come too. [K: Was he admitted for graduate work in physics at Princeton before this? If not, when? Get title of his senior thesis. Also the title of a paper that he published in Physical Review, and the names of his co-authors, and the date. Assuming he was already an enrolled graduate student, how much of his standard graduate work had he completed when he went to Leiden?]

Paul Ehrenfest and His Widow
(related to Peter Putnam)

Peter had remarkable ability to make contact with interesting people. Paul Ehrenfest no longer filled the chair of theoretical physics at Leiden. Ehrenfest was a man endowed with exceptional physical insight and analyzing power, but depressed at his own failure to make some great discovery. Depressed more at the fact that his son had been born mentally retarded. What would happen to that helpless boy if Hitler, then rising to prominence in Germany, should have his way in The Netherlands? Ehrenfest had a gun with him when he went to the hospital where his son lived. He killed the boy and then himself.

K: What year was this?

Peter told me that Mrs. Ehrenfest (also herself a distinguished physicist) was distressed that I had not paid a courtesy call on her. Being designated the Lorentz Professor at Leiden, I had already made a courtesy call on the widow of Lorentz. I must have spoken to her about the project I was promoting jointly with the American Physical Society and the American Philosophical Society to collect records and memories of the great figures of modern physics before it was too late. She told me that her husband had carefully collected his letters, arranged them into neatly labeled packages—and that she, after his death, had equally carefully burned them. When I called on Mrs. Ehrenfest, I told her that I hoped the same tragedy would not befall Ehrenfest's papers. We did not pursue the subject. However, months later, when I was back in Princeton going over the accumulated mail, as usual I put aside the big brown envelopes until the end. As I opened one, out poured a stack of postcards, the ones that Einstein had written over the years to Ehrenfest, the man he found most stimulating to talk to. I mentioned them to friends associated with the Einstein Papers project.

A month or so later, before I had time to get those postcards on their way, I received a call from Otto Nathan, the little man whose self-importance derived from his association as one of the executors of the Einstein estate. He started off with a threat to sue me if I did not immediately yield up those postcards. I'm happy that they are appearing in bits and pieces in their right chronological places in the great Princeton University Press Einstein Papers project. I know that Mr. Nathan later sued the Press for having John Stachel as the editor. It was (I think?) to Stachel that I gave the postcards.

Mrs. Nuijenhous
related to Peter Putnam)

Also on Zouderwoudsesingel, the street where Mrs. Ehrenfest lived, resided her friend Mrs. Nuijenhous (sp?). Peter invited her to lunch one day so that we could meet her, an 85-year-old treasure trove of history. She had been the daughter of one of the czar's generals and for her higher education went to the University of Zurich. Only once did she draw to the ready the pistol that her father had given her to take with her on the long train journey from Riga to Zurich. The train had been stopped for the night by a heavy snow in Poland. She was awakened in the middle of the night by the sound of footsteps prowling through the sleeping car. she suffered no interruption and put the pistol away after the intruder went off. At Zurich, she was accustomed to walk and talk with Einstein, and she saw him again when he made his annual visit to Leiden to talk with his old friend Ehrenfest. More than once in the library in Zurich she saw Lenin working away. She met a young Dutch student of archeology, married him, and went to live in The Netherlands. There, by agreement among the great powers, Kaiser Wilhelm II was interned after the end of World War I. He preserved that interest in archeology which had led in the pre-war period to the construction of the great museum xxx xxx and the reconstruction there of the beautiful altar of Pergamon. The Nuijenhouses became occasional guests of the Kaiser at Sunday dinner. What an epitome of history glowed in the bright countenance of that 85-year-old widow, with her memories of the czar, the Kaiser, Lenin, and Einstein!

Peter Putnam and Mrs. Putnam

To celebrate Alison's 14th birthday, we and Peter took her to the window seat in a restaurant that faced on a square in Leiden. Part way through the meal, a hurdy gurdy appeared outside the window, obviously arranged by Peter, with cheerful music to mark the occasion. Later in the spring, Mrs. Putnam came to visit. She discovered the terrible place where Peter was living to save money and worse, that through the influence of someone there, he had become a homosexual (to our surprise also), a sad species of humanity with which we had no previous acquaintance.

Peter Putnam (continued)
(for Chapter 9)

Gravitational waves and wave detectors, fluctuations in spacetime geometry, and describing electromagnetism as an attribute of geometry—the challenges to which Charles Misner and Joseph Weber and I directed our attention—did not engage Peter during this Leiden period, much though he helped the three of us by the magnificent poster-size drawings he got someone in Leiden to do. After Leiden, on his return to Princeton, however, Peter was engaged in and published, jointly with xxx, a study of where the mass-energy lies in a star that radiates at a prodigious rate. This work evolved into his Princeton thesis, for which he received the Ph.D. degree in 19xx.

He won a teaching appointment at the Fordham campus of New York University (?), then, the following year, at xxx on Long island. In the summer of 19xx, he filled in as a teacher in an undergraduate physics course at Columbia University. The seminar he ran in connection with this course had the flavor of the philosophical topics that were dear to him. It attracted students from the Union Theological Seminary near Columbia. The stimulus and sense of excitement that he produced led to his being given an appointment on the regular staff of Union Theological Seminary. One of the members of the Seminary told me that Peter was the only person he knew who could out-argue Reinhold Niebuhr, the great theologian and head of the Seminary. However, he did not publish. "Publish or perish" evidently holds as well in a theological seminary as in a research university's physics department. So Peter lost his job at this time.

American public opinion and the administration of Lyndon Johnson united to create an atmosphere favorable to winning civil rights for Negroes. Especially sensitive to these currents in the air, perhaps partly because of the climate of opinion at Union Theological Seminary, Peter decided to offer his services to Blacks in a little run-down seaside Louisiana community, Houma, located about xx miles south of Interstate 10. Janette and I stopped there in the summer of 1976 as we were driving from New Jersey to Austin, Texas to take up our new residence. Not a proper lawyer because he had only two years at Yale Law School, Peter represented many an indigent Black seeking his or her civil rights, but did this for a negligible or zero fee. Peter kept body and soul together by serving as a night janitor in a Houma church. One look at him was enough to show that he was truly impoverished. He would not swallow his pride enough to accept family money. His mother visited more than once from Cleveland, horrified though she was to discover that a black companion was living with him. Both wrote poetry and philosophical pieces too convoluted for this lowly physicist to understand, enthusiastically though Peter pushed his views on the walks we took around Houma. He nevertheless saw that they got informal publication. He also filled notebooks with writing that most educated people would find too etherial to grasp or accept.

In 19xx, cycling between his residence and his janitorial job late one night, Peter was hit by a drunk motorist and killed. One of his Union Theological Seminary students, xxx Clark (?), who now lives in Salt Lake City (?), to whom the writings and sayings of Peter meant much, has taken on the heavy task of being literary executor for Peter Putnam's daunting pile of manuscripts and notebooks.

Putnam Gift to Princeton for Art

When Peter moved from New Hampshire and half-time study of Eddington's book to full-time study at Leiden, he gave to Princeton University the stock in Sanders Associates (his New Hampshire employer) that he had in part earned and in part had been given as a bonus for his contributions. Keep these funds

segregated, he told the University, and do not sell the stock unless or until I give the instructions to do so. He realized that Sanders was going up and up. At a certain moment, he gave the University instructions to sell at what turned out to be the height of the market in Sanders. The yield for Princeton may have been more than $100,000. [Information probably resides in the University business office.]

Peter first proposed to President Goheen that this money plus an unstated additional amount from the family trust should go to the construction of a beautiful cathedral-like special building for the work in theoretical physics that I and others were doing. I recall the tension in the meeting with President Goheen, Mrs. Putnam, Peter, and me. President Goheen deplored, as I and other members of the department would, any fractionation of the department that would result in fewer of the interactions that make colleagueship at this university so precious. If not a work of art in the service of physics, why not then works of art for the inspiration of all who live and work on the Princeton campus? And of all forms of art today, did not modern sculpture offer the greatest in originality and leadership? The University happily accepted this change in the mission of the gift. With the advice and consent of the University and the Putnams, a committee came into being for the selection of the sculptures for the Princeton campus. Joseph Kelleher, Director of the Princeton Art Museum, served as chairman. Members included Sherman Lee, Director of the Cleveland Museum (to which the Putnams had already given numerous paintings); Thomas Hoving, Director of New York's Metropolitan Art Gallery (Museum?); and Walter xxx, Head of New York's Whitney Museum of Modern Art. Peter was effectively an active member of the committee, and through his influence I became what I can only call a kind of adjunct member of the committee.

The sculptures stand free in the open air here and there about the Princeton campus, delighting the casual art aficionado and serving as objects of pilgrimage for serious students of modern sculpture.

The Institute for Advanced Study already possessed a bust of Einstein done by Jacob Epstein. Gertrude Stein seemed to have no strongly marked connection with Princeton, so all debts of honor seemed to be paid to the three famous Steins, popularly known as "Ep and Ein and Gert." Niels Bohr, however, had a long and treasured connection with Princeton, so Peter and I wanted to see him honored, and the committee favored Marino Marini for the task. But he had never met Bohr and had no particular connection with the world of physicists. Therefore it fell to me to put together a collection of photographs of Bohr in various poses with various colleagues, interlaced with passages from his most striking statements, all translated and beautifully printed at Princeton. With this beautifully crafted book my forerunner by several weeks, I arrived in Milan and went to the residence of Marini. Unwilling to do a sculpture of a figure he did not know personally, Marini wanted to do an abstract figure on horseback, in the style of his famous sculpture of the condottieri Colleoni (?) in St. Marks Square in Venice (?), or . . .[another famous sculpture]. Bicycle often, motorcycle occasionally, but horse never did I see Niels Bohr ride, ride though King Frederick did on horseback through the streets of Copenhagen during the German occupation as sign and symbol that Denmark still lived.

Henry Moore
Sculpture and Rocks

The Marini enterprise came to nothing. My next enterprise for the Putnam committee came to a happier conclusion: Pick out a Henry Moore sculpture for the Princeton campus. In Paris at the time this request came, Janette and I flew to London, rented a car, and drove north less than fifty miles to the town of Muchhadham, where Moore lived. Miles out in the country at a little rural crossroads stood a grocery store and one or two houses. I stopped to enquire the way. "Henry? Why, he's just up the road a little piece. You'll see Henry's place on the left when you get there."

It was approaching noon when we arrived. Mrs. Moore expected us and invited us to lunch. We talked in the living room afterward and then were taken around the grounds to see the strategically located open-air sculptures. The themes for his sculptures Henry Moore conceived himself, never on commission from others. The piece chosen by the University of Chicago to commemorate the atomic bomb, though utterly appropriate in shape and design, had no connection with that theme in the beginning. One piece caught my attention above all others. Janette approved. With Henry Moore's approval, I recommended it to the committee. President Goheen, however, ruled it out because to buy it would consume too large a fraction of the Putnam sculpture fund. (It was around $150,000?) The committee settled instead on Moore's "Oval With Points." It retains continuing popularity with students, not least because it offers an attractive place for two friends to sit side by side and be photographed.

The hole through "Oval With Points" comported with Henry Moore's theory that every piece of sculpture that has a truly human cast always has somewhere a hole through it. Before we had to leave to get our plane out of London, Henry Moore took enough additional time to show us how he works. His workroom, perhaps ten feet square, bore bookcases on three of its walls. Black African carvings occupied one shelf, bones another, and xxx a third. In the center stood a table about the size of a folding card table, on it a stand consisting of a vase and a post perhaps six inches high, topped by a platform perhaps eight inches square. On it sat the clay which Moore was working up into the shape of his next piece. In the early hours of the morning, he had lain in bed thinking up the new conception. On arriving in the workroom after breakfast, he selected two or three pieces from each of the bookcases and laid them on the table to beam inspiration into the corners of his eyes. The clay maquette once done, Moore called in his assistant to make a replica a couple of feet high and wide. This Moore himself worked over, until he made it ready to go to the foundry in Berlin that was to cast the piece in full size. The foundry, he complained, got most of the money for his pieces.

Moore came to Princeton for the installation of "Ovals With Points" and was kind enough to visit the house we had built a few years before in Japanese style under the supervision of our Hungarian architect, Victor Olgyay. Where the driveway left the street, we had originally put in a few clusters of three or four stones, but admiration for the gardens of Kyoto made us look for boulders of monumental size. We drove several miles out in the country and locate three clusters of boulders that looked promising. The farmer who owned the first cluster said, "Rocks? I didn't know there were any rocks over in that corner of my field. No, you can't have them." Mr. Espenhorst, the contractor we had engaged to move the stones, looked over the other two clusters, each part of the debris from excavation associated with one or the other house under construction. Mr. Espenhorst brought the rocks that he had selected on a flatbed trailer, which also bore a front loader. With it, he unloaded the rocks onto the lawn and pushed them to the location we had selected in the center of the southerly view from our living room window. "Move this one" (and I was talking about three rocks taller than me) "three or four inches this way" and "three or four inches that way" as his ponderous machinery rolled and pushed. No laugh from him. He had served in the American Army in the Korean War and more than once had been in Japan on what the army calls R&R and what the rest of us know as Rest and Recreation. So he knew something of what we sought.

Henry Moore took an interest in nature's rival to his sculpture and advised us on planting about the base to comport with the triplet of peaks. Nineteen years later, we switched allegiance from the Japanese garden to the Chinese concept of rocks with holes that antedated by centuries Henry Moore's theory of the human predilection for the hole. In Suchow in 1981, we spent the better part of an hour in a garden consisting entirely of human-sized rocks with holes standing on monumental masonry bases. We asked one Princeton geologist after another, but with no satisfaction, where we could find rocks with holes. Finally, we asked Erling Lindorf. Negative at first, he thought harder and said, "Oh, now I remember one." "Where?" I asked eagerly. "In Colorado." My mind formed the image of me going to Colorado, renting a flatbed truck, retaining a contractor to load the rocks on it, and me driving the truck to Princeton. "Where in Colorado?" I asked eagerly. "Now I begin to remember, " said Erling as he racked his brain. "It was in Boulder—in front of the building of the Geological Society of America." If at three o'clock some morning that rock disappears, I'm afraid it will be all too obvious who took it.