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TOMONAGA, Shinichiro
Japanese physicist Born: Kyoto, March 31, 1906 Died: Tokyo, July 8, 1979 Tomonaga, the son of a noted philoso pher, graduated from Kyoto University in 1929, having been a classmate of Yukawa [1323]. He studied in Germany under Heisenberg [1245] for a time, then returned to Japan to obtain his doctorate at Kyoto in 1939. He taught at Tokyo University through World War II and, after its con clusion, worked out the theoretical basis for quantum electrodynamics as, simul taneously and independently, Feynman [1424] and Schwinger [1421] were doing in the United States. All three shared the 1965 Nobel Prize in physics. 810
[1301] GÖDEL
EWING [1303]
Tomonaga was appointed president of the Tokyo University of Education in 1956. [1301] GflDEL, Kurt (ger'del) Austrian-American mathematician Born: Briinn, Austria-Hungary (now Brno, Czechoslovakia), April 28, 1906
January 14, 1978 Godel studied at the University of Vienna, obtaining his Ph.D. in 1930. He then joined its faculty. In 1931 he published a paper that marked the culmination of the search for a new mathematical certainty, a search that had been going on for a full cen tury, since Lobachevski [484] and Bolyai [530] had shattered the old certainty of Euclid [40]. With the establishment of non-Eu clidean geometries, it had been realized that Euclid’s revered axioms were insuf ficient. Men like Hilbert [918] had estab lished new and far better axiom systems for geometry. Other mathematicians had used the symbolic logic of Boole [595] to try to establish axioms that would serve as a rigorous starting point for all of mathematics. Frege’s [797] attempt had been frustrated by Bertrand Russell [1005], whose own attempt, with White head [911], had been the most ambitious of all.
But two decades after the Russell- Whitehead structure had been published, Godel advanced what has come to be called Godel’s proof. He translated the symbols of symbolic logic into numbers in a systematic way and showed that it was always possible to construct a num ber that could not be arrived at by the other numbers of his system. What it amounted to was this: Godel had shown that if you began with any set of axioms, there would always be statements, within the system governed by those axioms, that could be neither proved nor disproved on the basis of those axioms. If the axioms are modified in such a way that that statement could then be either proved or disproved, then another statement can be constructed that cannot be either proved or dis proved, and so on forever. In still other words, the totality of mathematics cannot be brought to com plete order on the basis of any system of axioms. Every mathematical system, however complex, will always contain unresolvable paradoxes of the sort that Russell used to upset Frege’s system. Godel had ended the search for cer tainty in mathematics by showing that it did not and could not exist, just as Heisenberg [1245] had done for the physical sciences with his uncertainty principle five years earlier. Godel formed a connection with the Institute for Advanced Studies at Prince ton shortly after his paper was published. In 1940 he made the United States his permanent home and in 1948 he was naturalized an American citizen. [1302] BOK, Bart Jan Dutch-American astronomer Born: Hoorn, North Holland, April 28, 1906 Bok received his Ph.D. at the Univer sity of Groningen in 1932. By that time he had already spent time in the United States, and he became an American citi zen in 1938. He spent some twenty years thereafter on the faculty of Harvard University. From 1966 to 1974 he was at the University of Arizona. He is best known for his observation in the 1940s of certain comparatively small, compact, opaque, and isolated dust clouds. He suggested these—now called Bok globules—were stars in the process of formation. Most astronomers think he is right and some estimate that in our galaxy about ten stars are formed each year on the average. [1303] EWING, William Maurice American geologist
1906
Died: Galveston, Texas, May 4, 1974
Ewing was educated at Rice Institute (now Rice University) in Houston, 811
[1303] EWING
HESS [1304]
Texas, graduating in 1926 and obtaining his Ph.D. in 1931. After teaching at Pittsburgh University and Lehigh Uni versity, he joined the faculty of Colum bia University in 1944. From 1972 until his death, he was connected with the University of Texas at Galveston. After World War II, Ewing and his as sociates were engaged in numerous oce anic expeditions in the course of which the ocean bottoms were explored not merely by plumb lines, in the nineteenth- century fashion, but by all the resources of twentieth-century technology: ultra sonic reflection, gravity measurements, the punching out of long cores from the bottom, and so on. By these methods, modern oceanog raphy has revealed the ocean bottom to be as various a structure as the land sur face, with rugged mountain ranges, mys terious flat-topped mounts (guyots), peb ble-strewn regions, and other curiosity- rousing details. In particular, mid-ocean ridges like long mountain ranges have been discovered that dwarf those on the continents. The best known is the mid Atlantic ridge, winding down the center of the Atlantic Ocean. Ewing showed in 1956 that this ridge continued around Africa into the Indian Ocean and around Antarctica into the Pacific, forming a world-girdling system. Later, he showed there was a chasm or fault running down the center of the Atlantic ridge and spec ulated tMt the earth might be increasing its size. Later, it seemed more plausible that upwelling material through the rift was causing the sea bottom to spread, forcing the continents apart in some places and together in others. The flaw in Wegener’s [1071] scheme was cor rected. The continents did not drift through the underlying rock that was too stiff to allow it. The continents, fixed in the rock and forming crustal plates, were forced apart or together with the plates they were on by forces in the earth’s mantle. Ewing also suggested in 1952 that the presence of submarine canyons (deep rifts in the continental shelf, or relatively shallow ocean region, rimming the conti nents) was not caused by rivers running across the area at a time when the sea level was much lower, but by turbulent undersea flows of mud and sediment. Through the 1950s Ewing and his group accumulated evidence for a new theory explaining the cause of the peri odic ice ages as resulting not from a pe riod of cooling, but from one of warm ing. During the interglacial period, he maintained, the Arctic Ocean is free of ice cover and serves as a source of water vapor, which is deposited on the Siberian and Canadian shores as snow. The snow accumulates, the temperature drops, the glaciers move down from the north, and eventually the Arctic Ocean freezes over. Once it does, the source of snow is choked off, the glaciers begin to retreat, and the temperature rises, until as now the glaciers are mostly gone from the lowlands (though still lingering on Ant arctica and Greenland) while the Arctic Ocean remains frozen over. If warming continues to the point where the Arctic sea ice melts, the Arctic will then con tribute water vapor to the polar atmo sphere and the cycle will begin again. As to why the recurrent ice ages are only a recent feature of earth’s history (within the last few hundred thousand years) and did not appear for hundreds of millions of years before, there is the possibility that the North Pole has only been located in the landlocked Arctic in recent eras. Before then, it might have been located in the open Pacific where the great volume of circulating sea water would not permit ice formation and where there would be no nearby land surface to receive snow. [1304] HESS, Harry Hammond American geologist Born: New York, New York, May 24, 1906 Died: Woods Hole, Massachusetts, August 25, 1969 Hess graduated from Yale in 1927 and obtained his Ph.D. at Princeton in 1932. He commanded a submarine base in World War II and reached the rank of rear admiral in the Naval Reserve. His most glamorous work was done in connection with the oceans. For all the 812
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GOEP PERT-MAYER [1307]
thousands of years that man has been floating, sailing, or steaming across its surface, the land that lies under the wa ters has remained a mystery. It is only in recent decades that new means of ex ploring the depths have revealed that land. In 1945 Hess plumbed the greatest depth of the ocean—something like seven miles deep. He also studied the isolated mountains rising from the ocean floor (“sea-mounts”). Back in 1837 Charles Darwin had suggested that coral atolls were built up at a speed matching the natural sinking of the island. If this were so, it followed that some islands might (for the isostatic reasons suggested by Dutton [753]) sink without coral for mation and might now lie under the sea. Hess discovered, in 1946, that hun dreds of flat-topped sea-mounts underlie the Pacific Ocean, all probably sunken islands. These he named guyots in honor of the Swiss-American geographer A. H. Guyot [552]. In 1962, building on the findings of Ewing [1303], he presented evidence to the effect that the Atlantic seabed was spreading. This “sea-floor spreading” is crucial to the new science of “plate tec tonics” that is itself central to the new geology.
From 1934 Hess was on the faculty of Princeton, becoming head of the geology department in 1950. After 1965 he was an adviser to the National Aeronautics and Space Administration and helped plan the first landing on the moon, which took place a month before his death.
[1305] CRAIG, Lyman Creighton American chemist Born: Palmyra, Iowa, June 12, 1906
Craig graduated from Iowa State Uni versity in 1928 and obtained his Ph.D. there in 1931. After 1933 he was on the staff of Rockefeller University in New York. Craig pioneered in the careful frac tionation of complex mixtures by a vari ety of methods. His greatest feat of iso lating a rare item from a complicated mixture came in 1960, when he and his colleagues succeeded in isolating and pu rifying parathormone, the active princi ple of the parathyroid gland. [1306] CHAIN, Ernst Boris German-English biochemist
1906
Died: Ireland, August 12, 1979 Chain, the son of a chemist, was edu cated in Berlin, obtaining his Ph.D. in 1930 from the Friedrich-Wilhelm Uni versity. The even tenor of his life was interrupted by the coming to power of Hitler in early 1933. Chain saw the inevitable and left at once for England. There he worked under Hopkins [912] at Cambridge. In 1935 he was invited to Oxford by Florey [1213]. There he came across Fleming’s [1077] work on penicillin while investigating Fleming’s other discovery, lysozyme. He brought it to Florey’s attention and, to gether, they began work on the sub stance, for which Chain conducted the first chemical assay. For this, Chain shared in the 1945 Nobel Prize in medi cine and physiology with Florey and Fleming. Chain also discovered penicil linase, an enzyme that catalyzed the de struction of penicillin. After World War II, in 1948, Chain took the post of sci entific director at a health institute in Rome, lured by the thought of working with better equipment than he was able to obtain in Great Britain. By 1961, how ever, he was wooed back to the Uni versity of London, where a new labora tory was constructed for him. [1307] GOEPPERT-MAYER, Marie (ger'pert-may'er) German-American physicist Born: Kattowitz (now Katowice, Poland), June 28, 1906 Died: San Diego, California, Feb ruary 20, 1972 Marie Goeppert, born of many genera tions of professors, received her Ph.D. at 813
[1308] BETHE
BETHE [1308]
the University of Gottingen in 1930 under Born [1084]. She moved to the United States that same year and became an American citizen in 1933. She mar ried a physical chemist, Joseph Mayer, whom she had met in Gottingen, and, like Irène Curie, [1204] used a hyphen ated name thereafter. She was, along with her husband, at Princeton and Columbia, and then in 1945 she joined the staff of the Univer sity of Chicago. While there, in 1948, she suggested that the atomic nucleus consisted of protons and neutrons ar ranged in shells, as electrons were ar ranged in the outer atom. This theory, which was supported by Fermi [1243], made it possible to explain why some nuclei were more stable than others, why some elements were rich in isotopes, and so on. At about the same time, Jensen [1327] advanced the same notion independently, and in 1950 they collaborated on a book on the subject. Both she and Jensen ac cordingly shared the 1963 Nobel Prize in physics with Wigner [1036]. In 1960 she joined the faculty of the University of California at San Diego and remained there the rest of her life. [1308] BETHE, Hans Albrecht (bay'- tuh)
German-American physicist Bom: Strassburg (now in Bas- Rhin, France), July 2, 1906 At the time of Bethe’s birth, Alsace- Lorraine was part of Germany; it is now part of France. Bethe, the son of a uni versity professor, was educated at the universities of Frankfurt and Munich, obtaining his Ph.D. at Munich in 1928 under Sommerfeld [976], He worked under Ernest Rutherford [996] at Cam bridge and Fermi [1243] at Rome, then taught physics at Munich and Tubingen until 1933. In that year Hitler came to power and Bethe thought it the better part of valor to leave Germany. He taught in England until 1935 and then accepted a post at Cornell University in the United States. During his stay in England, Bethe worked out the manner in which high- energy particles, subjected to deflection by an electromagnetic field, emitted radi ation. This was of particular importance in cosmic ray studies. In the United States he was one of the scientists engaged in the development of the atomic bomb. In the postwar years he served on the American delegation in Geneva dining the long negotiations with the Soviet Union on the control of nu clear bomb tests. Bethe’s chief contribution to science was working out the details of the nu clear mechanisms that power the stars, which he achieved in 1938, when Weiz- sacker [1376] was independently reaching similar conclusions in Germany. Bethe made use of the knowledge of subatomic physics that had been collect ing in the forty years since Becquerel’s [834] discovery of radioactivity and Ed dington’s [1085] conclusions about the temperatures of the stellar interiors. Bethe’s mechanism resembled that suggested by Perrin [990] in a qualitative way as long before as 1921. It began with the union of a hydrogen nucleus (that is, a proton) with a carbon nu cleus. This initiated a series of reactions at the end of which the carbon nucleus was regenerated and four hydrogen nu clei (protons) had been converted to a helium nucleus (alpha particle). Hydro gen was thus the “fuel” of the star and helium the “ash,” while carbon played the role of catalyst. Stars like the sun were mostly hydro gen, so that there was ample fuel to last for billions of years, while the quantity of helium already present indicated that there had been prior existence for bil lions of years. Later Bethe evolved a sec ond scheme involving the direct union of hydrogen nuclei to form helium (in a number of steps) as a mechanism that could proceed at lower temperatures. Bethe’s nuclear mechanisms finally an swered the question that some three quarters of a century earlier had so con cerned Helmholtz [631] and Kelvin [652]: Where do the sun and stars obtain their energy? When hydrogen is con verted into helium (whether directly or by way of the catalytic influence of car 814
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PRELOG [1310]
bon) nearly 1 percent of the mass of the hydrogen is converted into energy. Even a little bit of mass is equivalent to a great deal of energy and so mass loss is ample to account for all the sun’s vast and eon-long radiation of energy. To be sure, at the rate the sun radiates energy it must be losing 4,200,000 tons of mass every second, but the total mass of the sun’s hydrogen is so great that this loss of mass must remain imperceptible even over millions of years. In 1961 Bethe was honored with the Fermi award (established in 1956) for his part in the development and use of atomic energy. In 1967 he received the Nobel Prize for physics. In his later years, Bethe became an ac tive proponent of the continued peaceful exploitation of nuclear energy. [1309] SCHAEFER, Vincent Joseph American physicist Born: Schenectady, New York, July 4, 1906 Schaefer’s education was very largely on the practical side. He worked in the machine shop at the General Electric Company in his hometown of Schenec tady, then thought the outdoors would suit his personality better. He graduated from the Davey Institute of Tree Surgery in 1928 and practiced that profession for a while. Economic necessity drove him back to General Electric and the in doors, however, and there he was no ticed by Langmuir [1072], whose assis tant he became in 1933. He rose to a research associate in his own right in 1938. In the 1940s Langmuir and Schaefer were studying the war-intensified prob lem of airplane wings icing up at high al titudes, creating great hazard. Just what factors caused the formation of ice or snow? This was of particular interest to Schaefer, who, as might be expected of an outdoorsman, was a ski enthusiast and snow lover. To experiment on this subject, Schaefer used a refrigerated box kept at —23 °C within which, it was hoped, water vapor could be condensed around dust particles into ice crystals. Finding what types of particles could be added artificially to hasten the crystal forma tion proved a baffling problem. In July 1946, during a hot spell, it was difficult to keep the temperature within the box low enough for the requirements of the experiments. Schaefer therefore dropped some solid carbon dioxide (dry ice) into the box in order to force down the temperature. However, as soon as the dry ice hit the interior of the box, the water vapor within condensed into ice crystals. The box was filled with a miniature snowstorm. Schaefer was soon ready to try a full- scale experiment. On November 13, 1946, he was flown by airplane over a cloud layer obscuring Pittsfield, Massa chusetts, about fifty miles southeast of Schenectady. Six pounds of pellets of dry ice were dumped into those clouds and a snowstorm started. It was the first man made precipitation in history. Since that day, rainmaking has passed from the medicine man’s ritual to the meteorologist’s technique. Dry ice gave way to the more convenient silver iodide, thanks to Vonnegut [1391], and there are few droughts in the United States now that do not bring on some effort at rainmaking. It is arguable whether rainmaking is truly effective—whether rain that is pro duced might not have fallen anyway. There is also the ticklish question of the legal responsibility in case a change in weather is construed by some to have been damaging to their economic or per sonal interests. Nevertheless, Mark Twain’s comment that “Everyone talks about the weather but nobody does any thing about it” has been refuted. [1310] Download 17.33 Mb. Do'stlaringiz bilan baham: |
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