• 15 •
IN DECEMBER 1958 Imme and I went to the San Diego airport to fly to Mexico City for our honeymoon. At that time we still had the new au pair, Margot Kaufner, to take care of the children. Imme had a brand-new German passport since her old passport had expired. The Mexican immigration official at the airport examined the passport and refused to let us fly. The expiration date on the passport said clearly that the passport had expired the day before it was issued. We must send the passport back to the German consulate and have a new one issued before we could travel. Four months passed before we could reorganize the honeymoon with Margot no longer available. We finally arrived in Mexico in March.
JANUARY 29, 1959, LA JOLLA
We had a letter from Hans Haefeli. He finally won his appeal to the Santa Rota in Rome. [This means the pope formally annulled his marriage to Verena. In the eyes of God, as interpreted by the Santa Rota, they were never married.] He will now marry a Swiss girl whom he has got to know in Boston. Katrin has met her and likes her, but I have not met her. Unfortunately this means he will go back to Switzerland for good. He has a job at a small engineering college in Luzern, and he will settle down there for the rest of his life. Undoubtedly this is the best solution for him, only I am sorry we shall have him no more to visit us in Princeton. He wrote me a very nice letter and said he has only understood, by what happened to me, what an idiot he was for so many years. I am very happy for him that he finally got away from his past too. For Katrin, this does not make much difference. She was not close to Hans anymore. There is no question of her going to live with him in Luzern. It is now entirely up to Verena to make some tolerable arrangement for Katrin.
I am sorry I have to abandon Katrin at this stage. I feel I am punishing her for her mother’s sins. But I have really no choice; Verena has legal control of Katrin, and so long as Katrin lives with us, this is bound to be troublesome. Verena’s future is also now more settled. She has taken a permanent job at San José State College. This is fifteen miles from Stanford. So she will continue to live where she now is. Kreisel will return to Reading for one more winter, and then come to a permanent position in Stanford in 1960. So it looks as if they will be able to provide a reasonably stable background for Katrin.
Margot Kaufner found herself a job with a family in La Jolla. So she left our household on Sunday. She seems happy at the new place, with five children under ten.
MARCH 26, 1959, MEXICO CITY
So here we are at last! Yesterday I achieved an ambition I have cherished since childhood by standing on the slopes of Popocatépetl [the gigantic volcano overlooking the valley where Mexico City stands]. What a magnificent mountain this is! A perfectly symmetrical peak with a crown of white snow. Needless to say, we did not climb it. It is 17,600 feet and takes twenty-four hours and a mule. What we did was just to get near enough to see it in its full glory. This takes some doing. Imme drove us in a beaten-up old Fiat car which we have rented. First she drove fifty miles over a “first-class” road, which means a road which was once tarred but is consistently narrow and full of bumps. Then came twenty miles of “second-class” road, which took us up to the pass about 11,000 feet high. The second-class road is barely endurable if one goes at fifteen miles per hour. It is hard dirt with pockets of soft sand, the surface ridged like a draining board. On the map there are also many third-class and fourth-class roads. But the map says before starting on these one should “seek local advice.” We decided the best advice would be to go on a mule. The pass is a magnificent place, a wide expanse of dry plateau with the snow peaks of Popocatépetl on one side and Ixtaccihuatl on the other. We walked up a little hill in the pass and looked through binoculars at the mountains and distant villages far below. Walking there is not an unmitigated joy, because the ground consists of the most penetrating black volcanic ash, which comes through everything and makes people and clothes uniformly grey.
The first days here we spent shopping and sight-seeing in the city. Yesterday was the first with the car. Today we took the car out again and went to see some ruins of pre-Aztec people, date about A.D. 500, at Teotihuacan. These ruins are also immense, and besides colossal pyramids and temples a certain amount of good fresco painting has survived. The pre-Aztecs seem to have been more cheerful people than the Aztecs. All the time here I am reminded of the days when I read Prescott’s Conquest of Mexico aloud to Mamma. I am glad I have this background to help understand things. But I am still woefully ignorant of the later history.
When my mother was growing old, she had eye problems that made reading difficult. I read many books aloud to her, including Prescott’s The Conquest of Mexico and The Conquest of Peru (1843 and 1847). Prescott’s books are written in a lively style, with a fast-paced narrative and vivid descriptions of buildings and landscapes. The monuments and mountains that I saw in Mexico were exactly as Prescott described them. I was amazed when I later learned that he had never visited either Mexico or Peru. He had eye problems too, and that made traveling difficult.
Generally speaking, the city is lovely, full of trees and parks and wide roads with even wider green strips on either side. There are many lovely old and new buildings. And still one is constantly shocked by the extreme poverty in the villages and in many parts of the city, the crowds of people hanging around the hotel district trying to sell knickknacks, many of them small children. Schools seem to be few and far between. We flew down here on Saturday, shall probably stay ten days and have three more at Acapulco on the ocean before flying home.
On Sunday we went to a bullfight in the big arena. This was not a good bullfight according to the experts, but it was exciting enough for me. The spectacle is impressive, and I should quickly become an aficionado if I lived here. You would not like it here, as the heat at midday becomes oppressive. Even for us it is exhausting from about eleven till three. One has to live like the Mexicans and take a siesta during the hot hours. It is pleasant to find the villages unspoilt, primitive, and picturesque. But for the people who live there, one can only hope they get spoilt as quickly as possible.
APRIL 7, 1959, LA JOLLA
Here we are, safe and sound after our two-week jaunt. The last three days turned out the best. Acapulco is what a seaside resort ought to be. The sea is warm so one can swim as long as one likes. In Acapulco we had no shopping or sight-seeing to do, and we could relax completely. We were in a hotel of the most satisfactory sort, a little bungalow for each family, equipped with icebox, cold drinks, and a jeep for driving around the rugged hills. We found the three children in excellent spirits when we returned. George and Esther stood at the door and threw rice over us as we came in.
APRIL 19, 1959, LA JOLLA
Now comes the sad news. Oliver will not be born in any inn or stable. Imme went to see her doctor, and he said Oliver is due approximately September 6. He said it is crazy to think of coming back from Europe in August, and even the trip out in July would be a serious risk in case of a bad-weather flight. So we decided to be sensible and have the baby here. We will drive home in time for the start of the institute term on October 1. It was Mrs. Peierls who said, “It is no use trying to have a baby at a convenient time. When they come, it is always inconvenient.”
Each of our daughters in turn was called Oliver, until he turned out to be a she.
Two breakfast conversations, one from yesterday and one from the day before.
Freeman, holding forth as usual like a professor: “Scientists are still trying to find out how pigeons can find their way home. We don’t know whether they can find their way by the stars.” George: “But I know that camels find their way by the stars.” Freeman: “How do you know that?” George: “Because when the three wise men were going to Bethlehem, the camels saw a star in the sky, and so they knew where to go.”
Esther is looking through an anthology of children’s poems: “That’s funny, I wrote a poem called ‘Daisy Song,’ and now I see another author has written one too.” Freeman: “Who is the other author?” Esther: “John Keats.”
MAY 19, 1959, LA JOLLA
We have a nightingale who sings each night outside our bedroom from about midnight for three or four hours. He stops just before sunrise when the chorus of other birds begins. He sings so loud it sometimes wakes us up, but it is no hardship to lie awake and listen to him. He sings alone, and it is impossible not to imagine a wealth of feelings behind this outpouring of song.
A Russian astronomer, Iosip Shklovsky, has suggested half-jokingly that the two moons of Mars are hollow. There is some evidence for this. The inner one has changed its revolution period faster than it should if it were solid. If they are hollow, then they are artificial, and the question is “Whose?” Shklovsky is a good astronomer and has done many sensible things before this. Now I am more than ever impatient to go there and have a look around.
SUNDAY, MAY 24, 1959, LA JOLLA
We just came back from a Sunday excursion to the Palomar telescope. This is only a two-hour drive from here, and it is through lovely country all the way. The observatory is 5,550 feet up, and the cold mountain air was most welcome to us. Also there is a little museum with thirty of the most striking pictures taken by the big telescope on view, properly illuminated with light coming through from the back. One never sees them so well when they are printed on paper. The big telescope, which started operations in 1949, is still unique in the world and still producing a large proportion of the important astronomy. It is surprising that nobody is thinking of building a bigger one. Even a second one of the same size would be enormously useful.
The astronomers are seriously interested in putting telescopes into space. Martin Schwarzschild in Princeton is a good friend of mine, and last year he flew a twelve-inch telescope several times in a balloon to eighty thousand feet, to take pictures of the sun. He had the telescope point itself automatically at the sun and take the pictures automatically. It all worked well, and he had some pictures sharper than any that had been seen before. Schwarzschild said the problems of operating a telescope in a rocket satellite are in some ways easier. He is already getting ready to send up a small telescope into orbit. I will be surprised if this is not done successfully within two years. I am interested in putting a bigger telescope higher up, for example on the moon. One of the attractions of our spaceship is that it could carry a big telescope up there with enough people and stuff to use it effectively.
After Einstein died in 1955, Niels Bohr was the greatest living physicist. He presided over European physics from his home in Copenhagen. Unlike Oppenheimer and most of the other senior physicists, Bohr believed strongly in the peaceful uses of nuclear energy. Freddy de Hoffmann invited Bohr to come to San Diego to give his blessing to the formal dedication ceremony of the General Atomic laboratories, and to our amazement Bohr said yes. He stayed at General Atomic for a week and was seriously interested in the details of our work. He was particularly interested in the TRIGA reactor and the Orion spaceship. As part of the dedication ceremonies, he pushed the switch to demonstrate the safety of our prototype TRIGA. The switch caused the control rods to be pulled explosively out of the reactor, so that the reactor was supercritical with a neutron doubling time of about two milliseconds. For a few milliseconds it was blowing up like a bomb. This was the worst possible situation that could happen in a reactor accident. The reactor power shot up in a few milliseconds to fifteen hundred megawatts, enough power to melt down the reactor in a few more milliseconds. But there was no meltdown. Instead, the power came down as fast as it went up, and the reactor settled down quietly to a power of one megawatt. The audience heard a loud bang when Bohr pushed the switch, and then silence. They were invited to walk by the reactor in its swimming pool and see the blue glow in the water around it. The automatic shutdown of the power after an accident was guaranteed by the laws of physics and did not require any human intervention. Bohr enjoyed the reactor like a boy playing with a new toy. He said he was sorry he was not able to include the launch of a real Orion spaceship in the dedication ceremony.
Yesterday we had a beautiful supper-picnic on the beach. A lot of our friends were there and also Niels Bohr and his wife. Old Bohr was here for the official celebrations when the laboratory was dedicated last week. Bohr stayed another week to talk to people and enjoy the scenery. For about half an hour Bohr talked to me alone as we walked up and down the beach. It was a tantalizing experience, as his voice is almost too low to hear, and each time a wave broke, his wisdom was irreparably lost. I learnt a lot about his struggles during the war to convince Roosevelt and Churchill that the atomic bomb was not something they could keep in their pockets. He believed then that the Russians would soon be making their own bombs and that the only chance to avoid a catastrophe was to bargain with Russia immediately for an abandonment of secrecy on both sides. Of course, he failed to convince Roosevelt and Churchill. But he said he had General [Jan] Smuts and Lord Halifax on his side.
I was glad that Bohr was enthusiastic about our spaceship. He thinks of it as something with which one may once again try to make a reasonable bargain with Russia. Of course, the difficulties now are in some ways greater than they were in 1944. But at least the secrecy problem is not so obsessive as it was then. The politicians have learned that secrets do not stay secret forever, and one can talk much more freely than in 1944. The problem is that we do not have much to offer Russia in return for opening up their country to us. I do not have much hope that we can solve the problems of war and peace this way. But I am glad if we try. Bohr encouraged me a lot.
SEPTEMBER 7, 1959, LA JOLLA
I got the children finally into bed. The house looks like a battlefield, but I will not try to tidy it up until Imme comes home. I take a few quiet minutes to write of the events of the day. It began at one a.m. with Imme gently waking me up. She said Oliver had begun hurting her around midnight, and it was now starting to feel serious. I timed the pains and found they were regularly at six-minute intervals. At one-thirty the interval changed to three minutes, so we telephoned the doctor and drove over to the hospital. We got to the hospital about two and found a great deal of commotion since three ladies had arrived in rapid succession. Because Imme had a first baby, they thought she would be slow and left her until last. However, about four they suddenly found out she was reaching the crisis, her doctor was summoned from his bed, and he arrived just in time to deliver a five-pound girl at 4:47. [At that moment Oliver became Dorothy.] The birth was quite simple and the baby started to scream at once. I was with Imme for a few minutes just before the birth, when the pains were severe. I came back an hour later and found her smiling and relaxed, everything over and already half forgotten. At six I drove home and had a fine time telling the children all about it. They were happy but not specially excited. They had been expecting this to happen each night since they arrived. Esther said she wants to marry young so that she can start having her own babies soon. This remark is a welcome change from her expressed intention to have no children at all, which she often used to assert when her mother was grumbling about the burdens of home and family.
George said when I put him to bed, “I am so excited about going to Princeton that I can hardly sleep. And I am excited most of all about the deep growly snowstorms.”
DECEMBER 18, 1959, PRINCETON
Last week I spent writing a political article about the problems of nuclear weapons. I hope to publish it in a quarterly magazine called Foreign Affairs which reaches a select and intelligent audience. The editor of Foreign Affairs is a young man who lives in Princeton. He brought off a tremendous success this year by getting a fifteen-page article by Khrushchev. He wrote to Khrushchev shortly before he came to America asking for an article, and back it came within a few weeks. The experts said it was undoubtedly written by Khrushchev because of details of style and phrasing. My article has to go to Livermore first to be scrutinized for secret information. When I get it back, I will send you a copy.
DECEMBER 31, 1959, PRINCETON
It is good to hear that you are enjoying Venus in the morning skies. Did you see in your newspapers that they have measured the surface temperature of Venus by looking at radio waves coming up through the clouds and they find an average temperature of 575 Fahrenheit? This was done at two different observatories independently, and the result is presumably correct. We had guessed it would be 100 or at most 150. This is an interesting puzzle, to understand why it is so hot. It is sad for the people who would like to go and see the place. Even at the poles one probably has an atmosphere consisting largely of superheated steam. This puts Venus permanently out of the running for colonization.
Later, when I looked more carefully at the problem, I concluded that colonization of Venus would not be impossible. If we put a big sun-shade in orbit around Venus, the atmosphere and the surface of the planet would cool down to a comfortable temperature in about five hundred years, and colonization could then begin. After the cooling, the main obstacle to colonization would be lack of water. That could be alleviated by importing water from icy asteroids or comets.
APRIL 7, 1960, PRINCETON
By good luck my article in Foreign Affairs appeared this week when everybody was interested in the subject. I had some busy days, with reporters calling from Washington and photographers coming to the institute to take my picture. I am pleased with the way this whole affair went. I have made a number of enemies by saying things people wish to be unsaid. But I now have a much easier feeling in my own mind. Whatever the government decides to do, I have done what I could to push them in a sensible direction. I do not have to feel responsible if my advice is not taken. I can now keep quiet and go back to working at physics with a good conscience.
The Foreign Affairs article was a political diatribe, arguing against an international agreement to stop the testing of nuclear weapons. I was emotionally opposed to a test ban treaty because it would forbid the nuclear tests that Orion would need before it could fly. When the Test Ban Treaty was signed in 1963, I had changed my mind and gave testimony supporting the treaty at the Senate ratification hearings. The Senate ratified the treaty with my blessing. By that time, I had given up hope that Orion could fly, and I was happy to join the majority who supported the test ban as a way to slow down the nuclear arms race. Orion was already dead, and the treaty was only one more nail in its coffin.
One surprise still remained for me. In December I showed my article to Oppenheimer before it was accepted by Foreign Affairs. I did this so that he could object to anything he found objectionable. He surprised me then by agreeing to everything and saying it was all right with him. Now after it appeared in print and some of his friends complained to him about it, he violently changed his mind. He gave me half an hour of tremendous scolding, saying that it was wrong to make any public statements about technical matters unless the statements were of such a kind that all experts would support them unanimously. This happened at a party in Oppenheimer’s house, while Imme stood by and listened in amazement. I shall certainly not follow Oppenheimer’s advice, nor has he usually followed it himself.
This is to me interesting, mainly in showing how unstable a character Oppenheimer is. This has always been at the root of his troubles. I am not worried for myself; it is now the third time that I had a tongue-lashing from Oppenheimer, and each time we remain friends. The first time was when I first came to the institute in 1948 and he objected to my physics. The second time was five years ago when he accused me of betraying some faculty secrets. On that occasion I really was at fault. Anyhow, with all his inconsistencies, I like him.
Yesterday I met Frank Drake, who is in charge of the project in West Virginia listening for radio signals from inhabitants of nearby planetary systems. So far they have tried two stars. Drake is a first-rate man, absolutely sound and full of common sense. He was here to talk to the astronomers about other things he has been doing, exploring the galactic center with radio. He said the big problem with the listening project is to be on guard against teenage pranksters with radiotransmitters (of which there are thousands in this country alone) who might enjoy fooling Drake with some plausible signals. Drake had a signal which seemed to be genuine for a whole month before he finally proved it came from Earth. Fortunately this did not get into the newspapers. My scheme of looking for unusual infrared emissions would alleviate this problem.
My proposal was to search for alien societies who were not interested in communication and could not be detected by radio. Any advanced society in the sky, whether or not it wished to communicate, could not avoid radiating waste heat into space. We could detect any large emission of waste heat with a telescope sensitive to infrared radiation. Many years later, telescopes in orbit searched for artificial sources of infrared radiation, but found no evidence for high-powered alien societies.
MAY 24, 1960, PRINCETON
I have occupied myself for the last few weeks with minor things. One of these was a little paper on the detection of intelligent beings in the universe [1960]. This was rather a crazy idea, but I think it is fundamentally right. I have still a strong belief there is a good chance we shall find evidence of intelligence in the universe if we look for it hard enough. This is not necessarily a remote prospect—it could happen within the next few years. I have also the naïve feeling that if we do find something of this kind it will have a profound effect on human behavior in general. It has always been true historically that the way to unite factions has been to find a common enemy. So the discovery of some rival civilization out there would have more effect in uniting humanity than any number of summit meetings. That is my belief. So I am in my own way fighting for peace too.
In August Imme and I traveled with our eleven-month-old Dorothy to England and Germany to meet her grandparents.
AUGUST 31, 1960, PRINCETON
Our trip home was comfortable, but we were three hours late in New York. In New York we missed all the convenient trains, and so we went to the bus station to wait for a bus to Princeton. At the bus station one could buy a quart of ice-cold milk, and so I took Dorothy’s bottle to the Men’s washroom to wash it out before refilling it. I felt rather foolish in the men’s room with this baby bottle and two huge soldiers washing their hands on either side of me. However, one of the soldiers after looking at me said, “Say, that’s not the right way to clean out a nipple. I’ll show you how to do that. It’s something I’m a real expert at.” So he showed me the expert way to do it, and I felt, well, this is America, and I am glad to be home.