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780 [1241] LAWRENCE
FERMI [1243]
celeration were invented, the first actu ally put into action being Cockcroft [1198] and Walton’s [1269] voltage mul tiplier. A far more spectacular particle accelerator was devised by Van de Graaff [1246], The key device, however, was supplied by Lawrence. It seemed to Lawrence that instead of trying to give protons or other charged particles one enormous “kick” by build ing up huge potentials, it might pay to have them move in circles and give them a small kick each time round. The small kicks would build up indefinitely. In 1930, therefore, he built a small de vice in which protons were made to travel between the poles of a large mag net that deflected their paths into circles. At each turn they received another push of electric potential. This made them move faster and therefore in a path that, under the constant force of the magnet, curved less sharply. Their path was a sort of spiral that brought them closer and closer to the rim of the instrument. By the time the charged particles finally shot out of the instrument, altogether, they had accumulated high energies in deed. Lawrence called the instrument a cy clotron. The first cyclotron was a small one, but larger ones were quickly built. By the time the 1930s came to an end, thirty-five huge cyclotrons had been built, twenty more were under con struction, and Lawrence was awarded the 1939 Nobel Prize in physics. The cyclotrons, according to original design, reached their limits by 1940, but modifications and improvements, intro duced by men like McMillan [1329], carried the energies to still higher levels. The advances in the understanding of nuclear physics in the last generation could scarcely have taken place without the use of the cyclotron and related in struments. During World War II Lawrence was busily engaged at Oak Ridge in one of the less successful attempts to separate quantities of uranium-235 from ordinary uranium, for incorporation into the “atomic pile” being built in Chicago by Fermi [1243]. He was one of those sci entists who, like Compton [1159] and unlike Franck [1081] and Szilard [1208], favored the use of the atomic bomb against Japanese cities and never felt any particular concern about the social as pects of the new weapon. After the war, he spent the final years of his life on nuclear research and in 1957 he won the Fermi award, the highest scientific honor the United States could offer. After his death, element 103, discov ered in 1961, was named lawrencium in his honor. [1242] HUGGINS, Charles Branton Canadian-American surgeon Born: Halifax Nova Scotia, Sep tember 22, 1901 Huggins graduated from Acadia Uni versity in 1920 and then went to the United States for his medical education. He obtained his M.D. from Harvard in 1924. After internship and residency, he joined the faculty of the University of Chicago Medical School in 1927 and remained there, becoming a naturalized American citizen in 1933. In 1941 Huggins showed that prostatic cancer in males could be controlled by the administration of female sex hor mone. This was the first indication that a major type of cancer could be controlled by purely chemical means. For this he shared with Rous [1067] the 1966 Nobel Prize in physiology and medicine. [1243] FERMI, Enrico (fehrimee) Italian-American physicist
1901
Died: Chicago, Illinois, Novem ber 28, 1954 Fermi received his doctor’s degree
Pisa in 1922, just a few months before Benito Mussolini seized power in Italy. Fermi did postdoctorate work in Ger many thereafter, under Bom [1084], but returned to Italy in 1924 and by 1926 was a professor of physics at the Univer sity of Rome, busily working out 781
[1243] FERMI
FERMI [1243]
theories as to the behavior of electrons in solids. Fermi grew interested in the neutron, as soon as that particle was discovered in 1932 by Chadwick [1150]. Neutral parti cles seemed to be his forte, for it was he who named the neutrino, which Pauli [1228] had postulated. Fermi went on to work out some of the mathematics in volved in neutrino emission. He also worked out the nature of what is now called the weak interaction, which is only a trillionth as strong as the elec tromagnetic interaction. Fermi’s work in this respect guided Yukawa [1323] in his elucidation of the strong interaction. The importance of the neutron was that with it many new types of nuclear reactions could be initiated. For one thing, the uncharged neutron was not repelled by the positively charged atomic nucleus, as positively charged alpha parti cles and protons were. For that reason, it was not necessary to build up neutron energies through the use of the acceler ators such as those constructed by Cock croft [1198], Van de Graaff [1246], and Lawrence [1241] for charged particles. Indeed, neutrons were more effective when they possessed less energy. Fermi discovered this when he noted that neutrons were particularly effective in initiating nuclear reactions if they passed through water or paraffin first. The light atoms in those compounds ab sorbed some of the neutron’s energy with each collision and slowed them to the point where they moved with only the normal speed of molecules at room tem perature. Such “thermal neutrons” stayed in the vicinity of a particular nu cleus a longer fraction of a second and were therefore more easily absorbed than fast neutrons. When a neutron is absorbed by the nu cleus of a particular atom, the new nu cleus sometimes emits a beta particle and becomes an atom of the next higher ele ment. It occurred to Fermi, therefore, in 1934 to bombard uranium with neutrons (fateful decision) in an attempt to form an artificial element above uranium in the periodic table. (No such trans uranium element was known to occur in nature.) Fermi thought for a while that he had actually obtained his new ele ment, which he called uranium X. To Fermi’s consternation, this possibility was prematurely disclosed by his supe rior and was loudly publicized by the Fascist press, anxious to advertise “Ital ian science” and to boast of a “Fascist victory.” Actually, Fermi was right to a certain extent, as McMillan [1329] was to show five years later. In the main, though, he was wrong. When Hahn [1063] investi gated the problem, it was eventually found that Fermi had a much bigger tiger by the tail than he had suspected. He was, without knowing it, playing with uranium fission. Nevertheless, for his work on neutron bombardment, particu larly with thermal neutrons, he received the 1938 Nobel Prize in physics, months before Meitner [1060] let the fission-cat out of the bag. However, these were increasingly bad times for the Fermis. Fermi was anti Fascist and at the Nobel Prize cere monies he did not wear the Fascist uni form or give the Fascist salute. Both would have been ridiculously out of place, but the controlled Italian press saw fit to castigate Fermi for these omis sions. Besides, Fermi’s wife was Jewish, and as Hitler’s influence became more pronounced in Italy, anti-Jewish laws were passed. From Stockholm, where Fermi accepted the prize, he and his family sailed to the United States, there to remain permanently. (He had been able to ready himself for this eventuality because Bohr [1101] had quietly hinted to him that he might win the prize.) He became professor of physics at Columbia University. Once in America, Fermi and others, like Szilard [1208], began to wonder if, in uranium fission, neutrons could be emitted that would then cause other uranium atoms to undergo fission, producing more neutrons and still more fission and so on. Such a nuclear chain reaction would produce incredible amounts of energy in a split second, all from one neutron, which might be sup plied from the stray quantities that were 7 8 2
[1243] FERMI
OLIPHANT [1244]
in the air all the time, thanks to cosmic rays.
When it was decided to establish the Manhattan Project and try to build a structure in which such a chain reaction might take place, Fermi was placed in charge of the actual building. He was, after Pearl Harbor, an “enemy alien” (he was not naturalized as an American citizen until 1944) but sanity prevailed and this was not allowed to interfere. Uranium and uranium oxide were piled up in combination with graphite blocks. The graphite served to slow neu trons to thermal velocities, and at those slow velocities neutrons were more easily absorbed by the uranium, and fission was more easily induced. (Fermi’s discovery of the decade before paid off here.) The structure was called an atomic pile be cause the blocks were piled up one atop the other and because the word “pile” used by itself gave no hint of the nature of the work. However, it was the first nuclear reactor, to use the correct term. The atomic pile worked. It contained cadmium rods to absorb neutrons until such time as the fission reaction was to be initiated. That moment came at 3:45 p . m . on December 2, 1942, in the squash court of the University of Chicago; when the cadmium rods were slowly withdrawn, the chain reaction became self-sustaining and the atomic age began. It was announced (among those in the know) by a cryptic telegram sent out by Compton [1159] that read, “The Italian navigator has entered the new world.” And, indeed, Fermi had accomplished a feat as earthshaking as that performed by that other Italian navigator, Co lumbus [121], four and a half centuries before, and with far greater potentialities for good and evil. In a little over two and a half years, such a fission reaction, arranged to build up to explosive vio lence, leveled two Japanese cities, with horrible loss of life, and ended World War II. Four years after that, the Soviet Union, under the leadership of Kurcha tov [1261], duplicated the American feat and the specter of nuclear war rose to plague a terrified mankind. In 1945 Fermi accepted a profes sorship at the Institute for Nuclear Stud ies at the University of Chicago, and under him a group of graduate students formed who included Gell-Mann [1487], Chamberlain [1439], Lee [1473], and Yang [1451], Fermi died young of stomach cancer; element 100, discovered the year after his death, was named fermium in his honor.
He lived long enough to see the devel opment by Teller [1332] and others of a far greater and deadlier nuclear weapon than the fission bomb. Like Op penheimer [1280] he opposed the devel opment of this more deadly H-bomb (or fusion bomb), although he had earlier approved the use of the fission bomb over Japan. He did not live to see his nu clear reactor put to other than explosive uses by Rickover [1225] and Hinton [1238],
[1244] OLIPHANT, Marcus Laurence Elwin
Australian physicist Born: Adelaide, South Australia, October 8, 1901 Oliphant graduated with honors in 1927, from the University of Adelaide, then went to Cambridge for his Ph.D., which he earned in 1929. Not long after the discovery of deu terium (hydrogen-2) by Urey [1164], Oliphant began to work with deuterons, the nuclei of the deuterium atom. He found, in 1934, that if he bombarded deuterium itself with deuterons, he formed a hitherto unknown atom of a still more complicated form of hydrogen, hydrogen-3. This new hydrogen isotope, called tritium, turned out to be feebly ra dioactive, the only radioactive form of hydrogen known. This work on hydrogen-isotope in teractions led, by the way, to work on hydrogen fusion and, eventually, to the development of the hydrogen bomb (and someday, one hopes, to useful fusion re actors as well). In 1943 Oliphant proposed a design for an accelerator more powerful than 783
[1245] HEISENBERG HEISENBERG [1245]
those then existing. Such accelerators— proton synchrotrons—were eventually built in the 1950s and 1960s and are now the most powerful tools of the sort that physicists have. [1245] HEISENBERG, Werner Karl (hy'zen-behrg) German physicist Born: Wurzburg, December 5, 1901
Died: Munich, February 1, 1976 Heisenberg’s father was a student of the humanities who became a professor specializing in Byzantine history. As a teenager after World War I, Heisenberg seemed far removed from the usual stereotype of the scholarly youngster. He engaged in street fights against the Communists in Munich and in later years was an enthusiastic moun tain climber. Nevertheless, his serious in terest was in science. At the University of Munich he stud ied under Sommerfeld [976], obtaining his Ph.D. in 1923. He worked as assis tant to Born [1084] at Gottingen and under Bohr [1101] in Copenhagen. Having worked with Bohr and Som merfeld, it would have been odd if he had not been interested in the Bohr-Som- merfeld atoms. So were other physicists, such as De Broglie [1157] and Schro dinger [1117], who were trying to present a more subtle picture of the atom than that offered by Bohr, by treat ing the electrons as wave forms rather than as simple particles. Heisenberg, however, abandoned all attempts at pictorialization. He believed that one should confine oneself to ob servable phenomena and not to imagi nary pictures. In this, he followed Mach’s [733] line of thinking of half a century earlier. The atoms devised by Bohr and others were intended to explain the positions of the spectral lines. Why not, therefore, begin with those lines and devise a math ematical relationship to account for them? This, Heisenberg did in 1927 dur ing a vacation on a North Sea island where he had gone to escape the discom fort of hay fever. He made use, with Bom’s help, of matrix algebra, evolving a system called matrix mechanics. This consisted of an array of quantities which, properly manipulated, gave the wavelengths of the spectral lines. It was equivalent, however, to Schrodinger’s wave mechanics announced only months later (as Neumann [1273] was eventu ally to show) and physicists found them selves more comfortable with the latter, which did allow some visualization. Heisenberg’s studies of nuclear theory led him to predict that the hydrogen molecule could exist in two forms: ortho hydrogen, in which the nuclei of the two atoms spun in the same direction, and para-hydrogen, in which they spun in opposite directions. In 1929 this was confirmed. Eventually his theory helped in the devising of methods for cutting down the evaporation rate of liquid hy drogen, and this in turn proved impor tant when large quantities of such liquid hydrogen were needed, a generation later, as rocket fuel. More startling still was the enunciation of another deduction in 1927, that of the uncertainty principle. This states that it is impossible to make an exact and si multaneous determination of both the position and the momentum (mass times velocity) of any body. The more exact one determination was, the less exact must the other be. The uncertainties of the two determinations, when multiplied, yielded a value approximately that of Planck’s [887] constant. This had the effect of weakening the law of cause and effect, which, except to a very few scientific philosophers, had been an unquestioned and unstudied an chor of science since the days of Thales [3] and the Ionian philosophers. Heisen berg’s uncertainty principle destroyed the purely deterministic philosophy of the universe. Laplace [347] had maintained that the entire history of the universe, past and future, could be calculated if the position and velocity of every parti cle in it were known for any one instant of time; and it was precisely these two pieces of information that could not be simultaneously known at any one instant of time. Even Einstein [1064], that revo 7 8 4
[1246] VAN DE GRAAFF VAN DE KAMP [1247]
lutionary thinker, found himself uncom fortable with this new way of looking at the universe. Heisenberg was awarded the 1932 Nobel Prize in physics for his enunciation of the uncertainty principle. After the discovery of the neutron by Chadwick [1150] in 1932, Heisenberg at once pointed out that from a theoretical standpoint a nucleus consisting of pro tons and neutrons was far more satis factory than one consisting (as had been thought for a decade and more) of pro tons and electrons. He maintained that the protons and neutrons would be held together in the narrow confines of the nucleus by means of exchange forces. What those forces might be, however, was not worked out until Yukawa [1323] tackled the problem. Heisenberg was one of the few top- notch scientists who found themselves able to work under the Nazis. He even accepted high positions under them— though it must be pointed out that re fusal of a position offered by them might well have been tantamount to suicide. During World War H Heisenberg was in charge of German research on the atomic bomb. Before success could be achieved, the war came to an end. Hei senberg was director of the Max Planck Institute at Berlin, but after the war he moved into West Germany and became director of the Max Planck Institute for Physics at Gottingen. [1246] VAN DE GRAAFF, Robert Jemison (van'duh-graf) American physicist Born: Tuscaloosa, Alabama, De cember 20, 1901 Died: Boston, Massachusetts, Jan uary 16, 1967 Van de Graaff attended the University of Alabama, graduating in 1922 as a me chanical engineer. After some years at the Sorbonne in Paris, where he attended the lectures of Madame Curie [965], he was awarded a Rhodes Scholarship and studied at Oxford, where he obtained his Ph.D. in 1928. After his return to America he worked first at Princeton University, then in 1931 joined the staff of the Massachusetts Institute of Tech nology.
He is best known for his high-voltage electrostatic generator, the first model of which was built in 1931. (Van de Graaff had worked out the principle two years earlier by using tin cans, a silk ribbon, and a small motor.) Actual models look like half dumb bells standing on end and slowly build up giant potentials that can accelerate particles to high energies. It made a dra matic display in the 1930s, producing potentials so high as to be able to give rise to spectacular bolts of “man-made lightning.’’ For practical purposes, how ever, it was outdistanced by Lawrence’s [1241] cyclotron. [1247] VAN DE KAMP, Peter Dutch-American astronomer Born: Kampen, Netherlands, De cember 26, 1901 After an education at the University of Utrecht, Van de Kamp went to the United States in 1923 and obtained his Ph.D. from the University of California in 1925. In 1937 he became the director of Sproul Observatory at Swarthmore College near Philadelphia. In 1942 he was naturalized an American citizen. Under his direction, astronomers at Sproul Observatory detected the first planets discovered outside our own solar system. In 1943 small irregularities of one of the stars of the 61 Cygni system showed the existence of a nonluminous component eight times the mass of Ju piter. In 1960 a planet of similar size to that component was located circling about the small star Lalande 21185. In 1963 a smaller planet, only 1.5 times Jupiter’s mass, was found to be circling Barnard’s [883] Star. Barnard’s Star is second closest to our selves, Lalande 21185 third closest, and 61 Cygni twelfth closest. That three planetary systems should exist in our immediate neighborhood is extremely unlikely unless planetary systems are common indeed, as theories of star formation like Weizsacker’s [1376] indi cate.
785 [1248] MORGENSTERN BRATTATN [1250]
[1248] MORGENSTERN, Oskar German-American economist Born: Görlitz, Silesia, January 24, 1902
Died: Princeton, New Jersey, July 26, 1977 Morgenstern taught economics at the University of Vienna, achieving profes sorial rank in 1935. However, Nazi Ger many absorbed Austria in 1938 and Morgenstern had to leave. He went to the United States and became an Ameri can citizen in 1944. He taught eco nomics at Princeton University, where he remained for the rest of his life, at taining professorial rank there in 1941. He was eager to apply mathematics to economics and, more broadly, to human strategies of all kinds—whether business, war, or scientific research—in order to maximize gains and minimize loss. He recognized that these principles applied to games as well, even something as sim ple as matching coins, and thus formu lated what became known as game theory. He collaborated with von Neu mann [1273], a fellow refugee, to write
[1249] LINDBERGH, Charles Augustus American aviator
ary 4, 1902 Died: Kipahulu, Hawaii, August 26, 1974 Lindbergh, the son of a Minnesota congressman, entered the University of Wisconsin in 1920 but interrupted his education as a mechanical engineer two years later to join a flying school. He bought his own plane and became an air mail pilot in 1925. At the time, a $25,000 prize was being offered to whoever made the first non stop flight across the Atlantic Ocean from New York to Paris. Lindbergh ob tained the backing of some St. Louis businessmen, purchased a monoplane, which he named “The Spirit of St. Louis,” and on May 20-21, 1927, ac complished the flight in thirty-three and a half hours. He became a hero of heroes at once as the United States exploded into vast demonstrations of worship. But the flight was more than a stunt. It, and the pub licity attending it, served an important purpose. In the quarter century since the Wright Brothers [961, 995] flew their plane, aeronautics had remained little more than a matter of stunting and thrills, as ballooning had been a century before in the time of Charles [343] and Gay-Lussac [420], There had been dogfights in World War I and some air mail service; but the general public did not take airplanes seriously as a means of transportation. Lindbergh’s flight, however, brought the airplane into public consciousness with a vengeance. The way was paved for the expansion of commercial flight. By the time another quarter century had passed, jet plane travel had arrived, the people of the world achieved a new mo bility, and the railroad after a century of domination since Stephenson’s [431] time, entered the gray years of decline. Following the golden days of his solo flight, Lindbergh served science by work ing with Carrell [1016] in designing an artificial heart for use in perfusing tis sues. He was also in the news twice in less happy fashion. In 1932 his first son, aged two, was kidnaped and murdered in a crime that made as great a sensation as had Lindbergh’s flight five years before. In the late 1930s he was one of the lead ing isolationists, fighting against partici pation of the United States in World War II.
[1250] BRATTAIN, Walter Houser American physicist Born: Amoy (now Hsiamen), China (of American parents), February 10, 1902 Brattain spent his youth on a cattle ranch and graduated from Whitman Col lege (in Walla Walla, Washington) in 1924 and obtained his Ph.D. at the Uni versity of Minnesota in 1929. He joined the staff of Bell Telephone Laboratories 786
[1251] STRASSMAN ALDER [1254]
in that year as a research physicist and during World War II worked on the magnetic detection of submarines. He shared the 1956 Nobel Prize in physics with Shockley [1348] and Bar deen [1334], In 1967 he accepted a professorial po sition at Whitman, his old alma mater. [1251] STRASSMAN, Fritz (shtrahs'- mahn)
German chemist Born: Boppard, Rhine, February 22, 1902 Strassman, a ninth child, was educated at Technological Institute at Hannover. When Meitner [1060] left Germany in 1938 under Nazi pressure, Strassman took her place and worked with Hahn [1063] on the problem of uranium fission. Neither was sympathetic to the Nazis but they maintained silence and were left to themselves. Strassman’s contribution to the work ing out of an understanding of uranium fission was recognized in 1966 when he shared with Hahn and Meitner in the Fermi Prize for that year. In 1946 he gained a professorial posi tion at the University of Mainz and in 1953 was made head of the chemistry department of the Max Planck Institute for Chemistry. [1252] KASTLER, Alfred German-French physicist
1902
When Kastler was bom, Alsace was part of Germany, but the region was transferred to France after World War I. Kastler began his teaching career in Al sace, held faculty positions in the prov inces and in 1941 became a professor at the University of Paris. In 1950 he developed a system of “op tical pumping’’ whereby atoms were illu minated with frequencies of light they were capable of absorbing. Momentarily they attained a high energy state then emitted light again. Kastler used both visible light and radio waves and from the manner of emission could deduce facts concerning atomic structure in a manner more elegant than was true of the heavier-handed earlier techniques of Rabi [1212], for instance. The technique led directly to the de velopment of masers and lasers and when Townes [1400] earned his Nobel Prize in 1964 for his work on the maser there was some dissatisfaction in France over the ignoring of Kastler. This was made up for when Kastler was awarded the 1966 Nobel Prize in physics. [1253] LWOFF, André Michael (luh- wawff) French microbiologist Born: Aulnay-le-Château, Allier, May 8, 1902 In 1927 Lwoff (of Russian-Polish de scent) received a doctorate in medicine and another in science, then joined the staff of the Pasteur Institute. He was ac tive in the French underground during World War II, and became an officer of the Legion of Honor. After 1959 he taught microbiology at the Sorbonne. It had already been known through the work of Beadle [1270] that genes were involved in the formation of en zymes. In the late 1940s and the 1950s Lwoff and his co-workers, Monod [1347] and Jacob [1438], showed that some genes were regulatory in function, ac tivating or inhibiting other genes. For this the three men shared the 1965 Nobel Prize in medicine and physi ology. Lwoff also showed that virus-DNA can be incorporated into cellular genes and be passed on in cell division. This is a form of mutation that could play a role in evolution. [1254] ALDER, Kurt German chemist Born: Konigshiitta, Silesia (now Chorzow, Poland), July 10, 1902 Died: Cologne, June 20, 1958 Alder, the son of a teacher, received his early education in his hometown, 787
[1255] GOUDSMIT
DIRAC [1256]
which became part of Poland after World War I. Alder and his family then left for Germany. After graduating from the University of Berlin, Alder went on for his Ph.D. at the University of Kiel, working under Diels [1039]. He obtained his degree in 1926 and two years later they worked out what is now called the Diels-Alder reaction and together they shared in the 1950 Nobel Prize in chemistry. In 1934 Alder had accepted a profes sorial position at Kiel and after 1940 was professor of chemistry at the Uni versity of Cologne. [1255] GOUDSMIT, Samuel Abraham Dutch-American physicist
July 11, 1902 Died: Reno, Nevada, December 4, 1978
Goudsmit’s professional life closely paralleled that of Uhlenbeck [1234]. To gether the two men studied at the Uni versity of Leiden and obtained Ph.D.s in 1927. Goudsmit worked with Uhlenbeck to demonstrate that Pauli’s [1228] fourth quantum number could be interpreted as particle spin. Like Uhlenbeck, Goudsmit also went to the United States in 1927 and worked at the University of Michigan and, dur ing World War II, at Massachusetts In stitute of Technology. In 1944 Goudsmit was one of those sent by the government to Europe to study the gradually increasing areas being liberated by the western Allies in order to find out what progress the Ger mans might be making in atomic bomb research. In 1948 Goudsmit joined the physics staff at Brookhaven National Laboratory. [1256] DIRAC, Paul Adrien Maurice (dih-rakO English physicist
August 8, 1902 Dirac, the son of a Swiss immigrant schoolteacher, studied electrical en gineering at Bristol University but, finding it difficult to get a job, switched to mathematics upon graduating in 1921 and eventually obtained his Ph.D. at Cambridge in 1926, having made a mathematical physicist out of himself. By 1932 he was Lucasian Professor of Mathematics at Cambridge (Newton’s [231] old post). Later, he married Wigner’s [1260] sister. During the late 1920s Dirac, like Schrödinger [1117], worked on the fur ther development of the mathematical studies begun by De Broglie [1157], in which particles like the electron were considered to have wave properties. Certain equations worked out by Dirac indicated that an electron could have two different types of energy states, one positive and one negative. This could be made to apply to the electric charge. Since the electron was negatively charged, there ought to be a similar par ticle positively charged. Naturally the first thought was that this other particle was the proton. How ever, the proton, although it did have a positive charge equal in size to the elec tron’s negative charge, was nothing like the electron otherwise. For one thing, it was 1,836 times as massive. In 1930 Dirac suggested that there must be a positive twin of the electron— one with the positive charge of a proton but a mass just equal to that of the elec tron. Naturally, the same equations held for the proton, so there should be a par ticle with a negative charge like that of the electron but with the mass of the proton. (Oppenheimer [1280] contrib uted importantly to this view.) These oppositely charged particles have come to be called antiparticles. Dirac’s theory, although it seemed far fetched when first published, was quickly confirmed by Anderson’s [1292] discov ery of the antielectron (better known as the positron) two years later. For the antiproton, a quarter of a cen tury had to pass, but that was finally de tected by Segre [1287]. Furthermore, particles not known in 1930 have been found accompanied by antiparticles and Dirac’s work has been upheld in every respect. There are even visions of forms 788
[1257] TISELIUS
TISELIUS [1257]
of matter made up of antiparticles only, as matter is made up of particles. It is conceivable that whole galaxies may be composed of such antimatter, but as yet no direct evidence for such a situation exists.
For his work on wave mechanics and for his theory of antiparticles Dirac shared the 1933 Nobel Prize in physics with Schrodinger. In 1940 he went to the Dublin Institute for Advanced Studies while retaining his seat at Cambridge. After his retirement, he accepted a post as professor of physics at Florida State University. [1257] TISELIUS, Arne Wilhelm Kaurin (tih-say'lee-us) Swedish chemist Born: Stockholm, August 10, 1902
Died: Uppsala, October 29, 1971
Tiselius, the son and grandson of mathematicians, lost his father when he was only four. He attended the Univer sity of Uppsala, earning his doctor’s de gree in 1928. For a number of years he served as assistant to Svedberg [1097] and in 1930 he joined the faculty of the university. In 1934 he spent a year at Princeton in the United States. While with Svedberg he became inter ested in the phenomenon of elec trophoresis (that is, the movement of charged particles in suspension or solu tion, under the influence of an electric field). Colloidal particles usually carry electric charges at various points on their surface. Added up, these yield a net charge which may be positive, negative, or zero, and which may be varied by adding acid or base to the solution. When an electric current is sent through the solution, the charged colloidal parti cles will travel toward either the negative or positive electrode, or will stand still, depending on the nature of the net charge. The rate at which they will travel will depend on the size of the net charge, the distribution of the individual charges, and several other factors. Now protein molecules in colloidal so lution carry electric charges and will move in an electric field. It is very un likely that two different proteins, how ever similar, would have just the same distribution of charge. And if the charge distribution was different, they would travel at different rates and separate. This had all been known before, but in 1937 Tiselius made electrophoresis a particularly practical method for study ing protein mixtures by devising a spe cial tube arranged like a rectangular U within which the proteins could move and separate. The Tiselius tube consisted of portions fitted together at specially ground joints that could be separated to isolate one of a mixture of proteins in one chamber. In addition, by the use of proper cylin drical lenses, it was possible to follow the process of separation by observing changes in the bending of light (changes in the “index of refraction,” in other words) passing through the suspension, as the protein concentration changed. These changes could be photographed as a wavelike pattern that could be used to calculate the quantity of each protein present in the mixture. Failure to separate into components under electrophoresis was good evidence of the purity of a protein preparation, particularly if there continued to be no separation when the acidity of the solu tion was changed. Electrophoresis was applied particu larly to the study of proteins of the blood, which could be separated into an albumin fraction and various globulin fractions. It might seem that by “finger printing” the blood in this way valuable diagnostic aid could be obtained, but un fortunately the blood protein mixture held surprisingly close to normal under all sorts of abnormal conditions, al though in a few cases there was a significant change. In 1938 Tiselius was appointed direc tor of the newly formed Institute of Bio chemistry and for his work on elec trophoresis, particularly in connection with blood, he was awarded the 1948 Nobel Prize in chemistry. In 1947 he became vice-president of the Nobel Foundation. 789
[1258] BROUWER
WIGNER [1260]
[1258] BROUWER, Dirk (brow'er) Dutch-American astronomer Born: Rotterdam, Netherlands, September 1, 1902 Died: New Haven, Connecticut, January 3, 1966 Brouwer, the son of a government em ployee, studied at the University of Lei den under De Sitter [1004] and obtained his Ph.D. in 1927. He then went to the United States on what might have been a temporary postdoctoral visit but received an offer from Yale University. He joined its faculty in 1928 and gained a profes sorial position in 1941 together with the directorship of the Yale Observatory. He became an American citizen in 1937. Brouwer worked on general orbital problems and in 1951 published a paper on the coordinates of the five outer planets from 1653 to 2060. The work is noteworthy because it represented the first use of a high-speed electronic com puter in solving an astronomical prob lem. From this time on, such computer use became common, and even essen tial, in many branches of science. Brouwer was elected to the National Academy of Sciences in 1951. [1259] SPEDDING, Frank Harold American chemist
(of American parents), October 22, 1902 Spedding, the son of a professional photographer, graduated from the Uni versity of Michigan in 1925, taking his degree in chemical engineering. He went on to the University of California, where he earned his Ph.D. in physical chemis try in 1929 under Lewis [1037], After teaching at Cornell, he moved on to Iowa State University in 1937. While working under Lewis, Spedding grew interested in the rare-earth ele ments, a group of fourteen metals so similar in properties that they are very difficult to separate and purify. Through the 1940s, Spedding developed an ion exchange procedure for their separation. This involved a column of resinous ma terial that had the ability to seize metal lic ions. The tendency to carry through this seizure varied from one metal to another; sufficiently so, even for metals as similar among themselves as the rare earths, as to make clear separation possi ble. Entirely because of this, individual rare-earth elements of high purity, virtu ally unobtainable before, became quite cheap afterward. When atomic bomb research moved into high gear in the early 1940s, un precedentedly pure uranium was required in large quantities. Spedding developed the necessary methods for that and in November 1942 his laboratory produced two tons of pure uranium as a contri bution toward the first “atomic pile.” After the war Spedding continued work on purifying substances and even made use of ion-exchange methods to separate isotopes of individual elements, producing almost pure nitrogen-15 by the hundreds of grams. [1260] WIGNER, Eugene Paul Hungarian-American physicist Born: Budapest, Hungary, November 17, 1902 Wigner, the son of a businessman, was educated as a chemical engineer (he was a classmate of Neumann [1273] in high school) and obtained his doctorate at the University of Berlin in 1925. He taught in Berlin and, until 1930, in Gottingen, where he worked with Hilbert [918], In 1930 he was invited (along with Neumann) to the United States, where he obtained a position as professor of mathematical physics at Princeton Uni versity and became an American citizen in 1937. In 1936 Wigner (a brother-in-law of Dirac [1256]) had worked out the theory of neutron absorption, a theory that proved useful indeed when it was time to build a nuclear reactor to make use of neutron absorption. He worked out the theory of conservation of parity, which, two decades later, Lee [1473] and Yang [1451] were to show did not apply in certain types of nuclear reactions. Wigner also showed that nuclear forces 790
[1261] KURCHATOV ECCLES [1262]
did not depend on electric charge, so that protons and neutrons within the nu cleus had similar properties in that re spect. This was a concept most useful to Yukawa’s [1323] meson theory. Wigner cooperated with Szilard [1208] to alert the United States Government to the need for developing a nuclear bomb, and then worked with Fermi [1243] and Szilard in Chicago to develop one. He also helped design the atomic instal lations at Hanford, Washington. After the war, he was director of research at the Clinton Laboratories at Oak Ridge for a time. In 1960 he re ceived the Atoms for Peace award and in 1963 shared the Nobel Prize in phys ics with Goeppert-Mayer [1307] and Jensen [1327]. [1261] KURCHATOV, Igor Vasilevich Soviet physicist
January 12, 1903 Died: Moscow, February 7, 1960
Kurchatov graduated in 1923 from the Crimean University in Simferopol, then joined the staff of Leningrad’s Physico- Technical Institute in 1925. In 1933 he grew interested in nuclear physics and in 1934 he obtained his Ph.D. in physics. He demonstrated branching in nuclear reactions and discovered the existence of nuclear isomers. In 1938 he was ap pointed head of the Nuclear Physics Laboratory of the institute. The Soviet Union was well aware of the potentiality of Hahn’s [1063] discov ery of fission and the disaster of German invasion did not keep the nation from exerting what effort it could in the direc tion of nuclear weapons. In February 1943 Kurchatov went to Moscow to as sume leadership of this research. The So viet Union was less well equipped scientifically than the United States and suffered much from the disorganization and destruction of World War II. Nevertheless, on Christmas Eve 1946, the Soviet Union put its first self-sustain ing reactor into action and in 1949, much sooner than many in America had expected, it developed an atomic bomb of its own. More surprisingly still, Kurchatov’s group went on to develop a hydrogen bomb in 1952, the same year as the United States, and then to build an ex perimental nuclear station for the pro duction of power for civilian use in 1954, some years before the United States did the same. Kurchatov worked in anonymity and it was not until 1956 that he was re vealed as the guiding spirit of Soviet nu clear research. He was elected to the Supreme Soviet (the analogue of the U. S. Congress, but a purely honorary position under the Soviet system of government) in 1950 and was reelected in 1954.
His ashes are entombed in the wall of the Kremlin. [1262] ECCLES, Sir John Carew (ek'ulz)
Australian physiologist Bom: Melbourne, January 27, 1903
Eccles graduated from Melbourne University in 1925 and went on to Ox ford as a Rhodes Scholar, obtaining his Ph.D. there in 1929. At Oxford he worked with Sherrington [881] on reflexes and on the nature of trans mission across the synapses. The work of Loewi [1015] and Dale [1034] made it seem likely that the im pulse crossed the synapse through chemi cal mediation rather than electrical. Eccles studied the action at synapses by means of microelectrodes inserted within the nerve cells themselves. He was able to work out the chemical changes in con siderable detail and for this shared with Hodgkin [1387] and A. F. Huxley [1419] the 1963 Nobel Prize for medi cine and physiology. In 1937 Eccles had returned to Aus tralia, teaching there and, for a period of time, in New Zealand. In 1958 he was knighted and in 1966 went to the United States to work at the Institute for Biomed ical Research in Chicago. 791
[1263] NATTA
BUTENANDT [1265]
[1263] NATTA, Giulio Italian chemist Born: Imperia, near Genoa, February 26, 1903 Died: Bergamo, May 2, 1979 Natta, the son of a judge, obtained a Ph.D. in chemical engineering in 1924 at the Polytechnic Institute in Milan, where in later years he became director of the Industrial Chemistry Research Center. In 1938 the Italian government made him director of research in the problems of preparing synthetic rubber. Upon hearing of Ziegler’s [1215] de velopment of metal-organic catalysts for polymer formation, Natta at once began working with propylene (ethylene to which a small one-carbon “methyl group” is attached). Within ten weeks he had found that in the polymer that re sulted all the methyl groups faced in the same direction, rather than being distrib uted randomly in different directions. Such “isotactic” polymers (the name was proposed by Natta’s wife) proved to have useful properties and could now be manufactured at will. As a result, Natta shared, with Ziegler, the 1963 Nobel Prize in chemistry. [1264] BOYD, William Clouser American biochemist
March 4, 1903 Boyd attended Harvard University, graduating in 1925. He joined the staff of Boston University School of Medicine in 1926 and remained there till his re tirement in 1968. He obtained his Ph.D. at Boston University in 1930. Boyd has concerned himself with the various blood groups that have been dis covered by Landsteiner [973] and others, and their distribution throughout the human race. No one blood group can be used to distinguish an individual of one segment of the human population from an individual of another, but average dis tributions are significant when large numbers of men are compared. During the 1930s Boyd and his wife, Lyle, traveled to various parts of the earth, blood-typing the populations. From the data so obtained and from similar data obtained from others, Boyd in 1956 was able to divide the human race into thirteen groups. Most of these follow, roughly, the divisions arrived at by rule-of-thumb or by consideration of such characteristics as skin color. One surprise is the existence of an early Eu ropean race characterized by the pres ence of unusually high frequencies of the Rh-minus gene. This was largely displaced by modem Europeans, but the older group has persisted in the moun tain fastnesses of the western Pyrénées and is known to us as the Basques. Blood group frequencies offer a method of racial distinction that does not involve visible characteristics and cannot, therefore, be used as a handy index for racism. Unaffected by environmental considerations, they do not suffer the dis advantages of Retzius’ [498] craniom etry. Furthermore, blood groups are mixed freely down the generations, since men and women are not influenced in their choice of mate by any consid eration of blood groups (as they might be by visible characteristics). Blood group frequencies can also be used to trace the course of prehistoric migrations, or even some that are not prehistoric. For instance, blood type B is highest among the inhabitants of central Asia and falls off as one progresses west ward and eastward. That it occurs at all in western Europe is thought by some to be the result of the periodic incursions of central Asian nomads into Europe. Of these, the Hunnish invasions of the fifth century a . d . and the Mongolian inva sions of the thirteenth are the most spec tacular.
[1265] BUTENANDT, Adolf Friedrich Johann (boo'te-nahnt) German chemist
Wesermünde), March 24, 1903 Butenandt did his undergraduate work at the University of Marburg and then in Download 17.33 Mb. Do'stlaringiz bilan baham: 
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