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JOLIOT-CUBIE [1227] Largely through Rickover’s drive, en ergy, and persistence, the project was carried through to completion. The U.S.S. Nautilus, launched in 1955, was the first of the nuclear submarines. Rickover’s scorning of convention, however, did not make him popular with old-line admirals of lesser ability, and it was only after considerable hesitation (and the application of popular pres sure) that Rickover was promoted to vice admiral in 1959. Although the nuclear submarine is pri marily a war weapon, it has also served science. Its fuel supply lasts for months and it does not need to surface to charge batteries. In 1958 the Nautilus crossed the Arctic Ocean underwater from the Pacific to the Atlantic, thus initiating the study of the Arctic depths. Nuclear sub marines also serve as an interesting method of keeping men closely confined over long periods of time—with results that may be useful in solving the psycho logical problems that will undoubtedly accompany prolonged space flight. Rickover was awarded the 1964 Fermi award by the Atomic Energy Commis sion. It amounted to only $25,000 on that occasion for the cash value of the award had been pettishly reduced by half because of Congressional response to the fact that Oppenheimer [1280] had been granted the award the year before. [1226] LONDON, Fritz Wolfgang German-American physicist
Wroclaw, Poland), March 7, 1900
March 30, 1954 London, the son of a Jewish professor, received his Ph.D. summa cum laude in 1921 from the University of Munich. The dissertation was on philosophy, but he returned to Munich in 1925 to work on theoretical physics under Sommerfeld [976] and later worked with Schrodinger [1117]. The coming to power of Hitler drove London out of Germany in 1933. After some years in Great Britain and France, he was appointed to a profes sorial position at Duke University in North Carolina and remained there the rest of his life. In 1927 he had worked out a quantum mechanical treatment of the hydrogen molecule, which provided a strong theo retical basis for the study of molecules generally in terms of the new physics, and which laid the groundwork for the resonance theory of Pauling [1236]. [1227] JOLIOT-CURIE, Frédéric (zhoh-lyoh-kyoo-reeO French physicist Born: Paris, March 19, 1900 Died: Paris, August 14, 1958 Joliot-Curie was born Jean Frédéric Joliot. He was the son of a merchant who had taken an active part on the side of the radicals in the Paris Commune of 1870. He was brought up without reli gion and remained an atheist all his life. He added his wife’s name to his own when he married Irène Curie [1204], the daughter of Pierre and Marie Curie [897, 965], not willing (since the Curies had no sons) to let a name so famous in science be wiped out in favor of his own. He had obtained a degree in engineer ing from the School of Physics and Chemistry in Paris in 1923. In 1925 he attracted the attention of Langevin [1000], through whose recommendation he became special assistant to Marie Curie and in 1926 married her daughter. After 1931, the Joliot-Curies worked to gether as the Curies had done before them, and like the Curies they worked on radioactivity. Frédéric concentrated on the chemical aspects (and obtained his Ph.D. in that subject in 1930). Irène on the physical. On two different occasions, they missed great discoveries by a hair. In 1932 they were within an ace of discover ing the neutron but lost out to Chadwick [1150], Then in 1933 they had the posi tron almost at their mercy and lost out to Anderson [1292]. In 1934, finally, lightning struck. They were studying the effect of alpha parti cles on light elements such as aluminum. They knocked protons out of the alumi 771 [1227] JOLIOT-CURIE PAULI
num nuclei in the course of the bom bardment, very much as Ernest Ruther ford [996] had been doing in similar ex periments for fifteen years. However, at one point the Joliot-Curies discovered that after they had ceased alpha particle bombardment, and protons ceased being emitted by the target, another form of radiation continued. The Joliot-Curies decided that as a re sult of the bombardment of aluminum, they had formed phosphorus. Nor was this phosphorus the ordinary form. Their reasoning showed it had to be an isotope that did not occur in nature and that had to be radioactive. After they had stopped their bombardment, the new radioactive isotope of phosphorus they had formed kept right on breaking down. This was the source of the continuing radiation. What the Joliot-Curies had done was to discover “artificial radioactivity.” It was now realized that radioactivity was not at all a phenomenon confined to the very heaviest elements like uranium and thorium. Any element could be radioac tive if the proper isotope was prepared. Since that day in 1934 over a thousand different radioactive isotopes have been prepared, at least one (and sometimes a dozen or more) for every known ele ment. These artificial radioactive isotopes (also called radioisotopes) have proved far more useful in medicine, industry, and research than any of the naturally radioactive materials. For this work the Joliot-Curies were awarded the Nobel Prize in chemistry in 1935, the third Nobel Prize to go to the Curie family, although Marie Curie failed by a year to live to see her daugh ter and son-in-law so honored. Just as World War II started, Joliot- Curie discovered that in uranium fission, neutrons were produced. He therefore began work on the development of an explosive chain reaction, research which, in the United States, was eventually to produce a nuclear bomb. Joliot-Curie might have got there first, but for the war.
The German conquest of France in 1940 interrupted him. The Joliot-Curies managed to smuggle the heavy water (the only sizable quantity in the world) necessary for atomic bomb research out of the country and out of the grasp of the Germans. (Their uranium was hid den, then reclaimed after the war and used to build France’s first nuclear reac tor in 1948.) The Joliot-Curies them selves remained behind in order to help organize resistance to Hitler. In 1944 Joliot-Curie helped Langevin to escape to Switzerland, then did the same for his wife and finally went into hiding himself. After the war Joliot-Curie returned to work on a nuclear reactor and was made head of the French atomic energy com mission by Charles de Gaulle. In 1948 the reactor was completed and it worked. It had been built in France, in dependently of the Anglo-American know-how. However, as it turned out, Joliot-Curie was an admitted Commu nist, having joined the party during World War II after the Nazis had exe cuted Langevin’s son-in-law. He was therefore removed from his position in 1950 and was replaced by his friend Per rin [990], In 1951 he was awarded the Stalin Peace Prize, and for the rest of his life he remained an outspoken Commu nist. [1228] PAULI, Wolfgang Austrian-American physicist Born: Vienna, Austria, April 25, 1900
Died: Zürich, Switzerland, De cember 14, 1958 Pauli, the son of a professor of colloid chemistry, was a youthful prodigy and his godfather had been Mach [733]. While still a teenager, he was writing formidably lucid articles on relativity that were admired by Einstein [1064] himself. He studied under Sommerfeld [976] at the University of Munich and obtained his doctor’s degree there in 1921. After postdoctorate work with Bohr [1101] at Copenhagen and with Bom [1084] at Göttingen, he joined the faculty of the University of Hamburg in 1923 and the Zürich Institute of Technology in 1928. He was impossibly clumsy with his hands and was a poor and stumbling lec turer; but it was his brain that was non- pareU. In 1925 he announced his exclu-
[1228] P a u li OORT [1229] sion principle. His teachers, Bohr and Sommerfeld, had worked out the energy levels of the electrons within atoms. These could be expressed as quantum numbers, which could be stated accord ing to certain simple rules. There were three quantum numbers altogether. Pauli, after long consideration of the Zeeman [945] effect, capped the struc ture by allowing for a fourth. This fourth quantum number could be inter preted as supposing that in any particu lar energy level, two and only two elec trons could be permitted, one spinning clockwise and one spinning coun terclockwise. Once this was allowed, it was possible to arrange the electrons of the various el ements in shells and subshells. If the chemical properties of an element were assumed to depend on the number of electrons in the outermost shell, then Mendeleev’s [705] periodic table was ac counted for. The various elements in the first column (lithium, sodium, potas sium, rubidium, cesium) are all similar chemically, because all have a single electron in the outermost shell. They have different numbers of shells inside that outermost one so that they have different atomic weights and vary in chemical detail. In the broad strokes, however, they are similar. The same holds for other rows of the periodic table, which thus completed the ratio nalization that had begun with Moseley’s [1121] discovery of the atomic number. For this important discovery Pauli re ceived rather belated recognition in the form of the award of the 1945 Nobel Prize in physics. Meanwhile, he had not rested on his oars. In the 1920s it was discovered that atoms emitting beta particles (speeding electrons) did so with less energy than they should. Some energy was apparently being destroyed and the law of conser vation of energy might have to be aban doned. This, physicists did not want to do without overwhelming cause (though Bohr is reported to have been on the point of doing so). In 1931 Pauli suggested that when a beta particle was emitted, another parti cle, without charge and perhaps without mass either, was also emitted and that this second particle carried off the miss ing energy. In the next year Fermi [1243] named Pauli’s postulated particle the neutrino, which is Italian for “little neutral one.” Without charge and without mass, the neutrino is practically indétectable. For nearly a quarter of a century, it was the mere ghost of a particle and many scien tists thought uneasily that it was simply a “gimmick” to save the energy book keeping and preserve the law of conser vation of energy. In 1956 the neutrino was finally detected and proved to exist by a very elaborate experiment involving a nuclear power station (which did not exist in 1931 ). Pauli lived to see his conjecture proved.
The neutrino, for all its evanescence, can have huge effects. In 1962, for in stance, a theory was advanced wherein supernovas exploded through reactions involving neutrino formation. In the 1930s Pauli was often in the United States and, with the coming of the war, he made his home there and joined the Institute of Advanced Study at Princeton, becoming an American citi zen in 1946. [1229] OORT, Jan Hendrik (awrt) Dutch astronomer
Oort was the son of a physician and the grandson of a professor of Hebrew. He studied under Kapteyn [815] at the University of Groningen, obtaining his doctorate in 1926. He spent his pro fessional life at Leiden Observatory, entering it in 1924 and becoming its director in 1945. He had been Kapteyn’s last student so it was rather fitting that he continued his teacher’s studies of the motion of the stars in mass. In so doing he was able to reduce Kapteyn’s two star streams to something even more orderly, for he could show in 1927 that our galaxy was rotating about its center (something Lindblad [1185] was independently demonstrating). Since the galaxy is not a solid mass, but con sists of individual bodies, it does not ro
[1229] O ort GABOR [1230]
tate all in one piece. Instead, the stars nearer the galactic center move faster than those farther from the center, just as the inner portions of Saturn’s rings move faster than the outer, and just as the inner planets of the solar system revolve about the sun at a more rapid velocity than the outer ones. It follows that those stars nearer the galactic center than our own sun, gain on us; in turn, our sun gains on the stars farther from the center than we are. There are Kapteyn’s two streams, one group moving ahead and one falling behind, which in 1927 Oort reinterpreted by this picture of a rotating galaxy. From the motion of the stars near us, Oort was able to show that the center about which they were revolving lay in the constellation Sagittarius and in this he disagreed with Kapteyn and agreed with Shapley [1102]. In 1930, however, making allowance for Trumpler’s [1109] discovery of dust clouds, which absorbed sunlight and made distant star clouds look fainter and therefore more distant than they really were, he scaled down the size of the galaxy. He calculated the distance of the galactic center at 30,000 light-years instead of Shapley’s 50,000, and in this respect it is Oort’s figure that is now accepted. It could be shown, too, that the sun completes its revolution about the galac tic center in about 200,000,000 years. From this period of revolution and from the distance of the sun from the galactic center, it could further be shown that the mass of our galaxy is about equal to the mass of 100,000,000,000 stars the size of our sun. Knowledge concerning the general structure of our galaxy dates from this work of Oort, who has gone on to spe cialize in the details of galactic structure. After the discovery by Jansky [1295] of radio-wave emission from outer space, the key tool in studying the galaxy came to be radio telescopy. Radio waves could penetrate the dust clouds that remained opaque to ordinary light, so that by radio telescope the galactic center (for ever hidden to our ordinary vision) could be studied. The best means for such study was worked out during World War II, amid the hardships of the German occupation of the Netherlands. With the land pros trate, the observatory closed, instruments unavailable, nothing was left but the un conquerable mind. One of Oort’s group, Van de Hulst [1430], spent his time car rying through calculations in 1944 that made it seem as though the electron and proton making up a hydrogen atom ought, once in several million years or so, spontaneously to switch orientation with respect to each other and, in so doing, emit radio-wave radiation at a wavelength of 21 centimeters (about 8 inches). The amount radiated by any ordinary quantity of hydrogen would be far too small to detect, of course, but the quantities of hydrogen thinly spread between the stars ought to amount, in total, to a mass large enough to radiate a detectable amount. With the war over, and Holland free once more, it became possible to attempt to confirm this purely theoretical deduc tion. In 1951 Oort and his group did just this. They detected “the song of hydro gen.” The pattern traced out by this “song” has allowed astronomers to fol low the spiral structure of the galactic arms where the concentration of hydro gen is highest. For this reason the decade of the 1950s saw the spiral structure of our galaxy mapped out in some detail. Oort in 1950 propounded an ingenious theory concerning the origin of comets. He suggests that the comets make up a vast cloud of minor planets enveloping the sun in a huge asteroid belt at a light- year’s distance or thereabouts. Small numbers of these are continually being hurled into the solar system proper through the gravitational perturbations of the nearer stars. About 20 percent of the original supply of comets, Oort esti mates, have been hurled inward thus. [1230] GABOR, Dennis Hungarian-British physicist
5, 1900
Died: London, England, Febru ary 9, 1979 774
[1231] KREBS KREBS
[1231] Gabor obtained his doctoral degree in Germany in 1927, but with the coming to power of Hitler he left for England, where he served as a professor of physics at the University of London. In 1967 he went to the United States to work at the Columbia Broadcasting System Labora tories at Stamford, Connecticut. While in England he worked on the electron microscope and got the idea of holography. In ordinary photography, a beam of reflected light falls on a photo graphic film and a two-dimensional pho tograph of a cross section of that beam is taken. Suppose instead that a beam of light is split in two. One part strikes an object and is reflected with all the irregularities that this object would impose on it. The second part is reflected from a mirror with no irregularities. The two parts meet at the photographic film, and the interference pattern is photographed. If light is then shone through the film, it takes on the interference characteristics and produces a three-dimensional image with far more information than the flat photograph. Gabor worked out the theo retical backing of holography in 1947, but it was not reduced to a practical working technique till 1965. As a result, Gabor received the 1971 Nobel Prize for physics. [1231] KREBS, Sir Hans Adolf German-British biochemist Born: Hildesheim, Hannover, Germany, August 25, 1900 Died: Oxford, November 22, 1981 Krebs, the son of a Jewish physician, received his education at several German universities, obtaining his medical degree in 1925 from the University of Ham burg. He practiced as an ear, nose, and throat specialist, but was drawn to re search. He worked as an assistant to Warburg [1089] from 1926 to 1930. Thereafter, he grew interested in the breakdown of amino acids, the building blocks of proteins. Amino acids might be used for the construction of proteins, but under many circumstances they could be broken down for energy. In the latter case the first step was to remove the ni trogen atoms they contained (deamina tion), and it was Krebs who first ob served the process. The nitrogen atoms were eliminated from the body in the form of urea (the artificial synthesis of which by Wohler [515] a century earlier had initiated modern organic chemistry). In 1932 Krebs worked out the manner in which urea was formed, by way of the break down and regeneration of a portion of the molecule of the amino acid arginine. The urea cycle has been more detailed in the generation since; but its main skele ton is still as Krebs laid it out. With the advent of Hitler, Krebs could no longer remain in Germany. He went to England in 1933, studied at Cam bridge, and by 1934 joined the faculty of the University of Sheffield, moving on to Oxford University in 1954. Krebs, working under Hopkins [912], took up the matter of carbohydrate metabolism. Meyerhof [1095] and the Coris [1192, 1194] had dealt with those changes that carried the glycogen of the liver down to lactic acid. That portion of the change, however, did not involve the absorption of oxygen and produced only a comparatively small amount of energy. The lactic acid must somehow be broken down to carbon dioxide and water and in the process must take up oxygen. Warburg, Krebs’s old superior, had measured oxygen uptake, but that alone had yielded no insight into the details of the change. Szent-Gyorgyi’s [1167] finding, that once oxygen uptake rates declined they could be restored by any one of four four-carbon acids, was a beginning. Krebs went on to locate two six-carbon acids, including the well-known citric acid, that did the same thing. All must be involved in the chain that led from lactic acid to carbon dioxide and water. By 1940 the manner in which all these compounds fit together was worked out by Krebs. The result was a cycle; that is, a re generating series of chemical changes. The lactic acid, a three-carbon com pound, was broken down to a two-car bon compound, the exact nature of which was later worked out by Lipmann
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