Biographical encyclopedia
Download 17.33 Mb. Pdf ko'rish
|
|
676 [1064] EINSTEIN
EINSTEIN [1064] one to northern Brazil and one to Prin cipe Island in the Gulf of Guinea off the coast of West Africa. The positions of the bright stars near the sun were mea sured. If light was bent in its passage near the sun, those stars would be in po sitions that differed slightly from those they occupied six months before, when their light passed nowhere near the sun as they rode high in the midnight sky. Again the comparison of positions backed Einstein. Einstein was now world-famous. Ordi nary people might not understand his theories and might only grasp dimly what it was all about but there was no question that they understood him to be the scientist. No scientist was so revered in his own time since Newton. This, however, was not to save Einstein from the malevolent forces that were begin ning to sweep Germany. In 1930 Einstein visited California to lecture at the California Institute of Technology and was still there when Hitler came to power. There was no point in returning to Germany, and he took up permanent residence in Prince ton, New Jersey, at the Institute for Ad vanced Studies where, a year before, he had already been offered a post. In 1940 he became an American citizen. The final decades of his life were spent in a vain hunt for a theory that would embrace both gravitation and elec tromagnetic phenomena (the unified field theory) but this, to his increasing distress, eluded him and, so far, it has eluded everyone else. Nor did Einstein succeed in accepting all the changes that were sweeping the world of physics, de spite his own role as intellectual revolu tionary. He would not accept Heisen berg’s [1245] principle of uncertainty, for instance, for he could not believe that the universe would be so entirely in the grip of chance. “God may be subtle,” he once said, “but He is not malicious.” In 1930 he had argued that the uncer tainty principle implied that time and en ergy could not be simultaneously deter mined with complete accuracy. He pre sented a “thought experiment” to show that this was not so and that time and energy could be determined simulta neously to any degree of accuracy. The next day, however, Bohr [1101], having spent a sleepless night, pointed out an error in Einstein’s argument. Now the time-energy uncertainty is accepted. With the beginning of World War II, Einstein was instrumental in achieving something he did not want. Uranium fission had been discovered in 1939 by Hahn [1063] and Meitner [1060], and Szilard [1208] could see quite well what that implied. Szilard did not want the horrors of nuclear bombs to be released on mankind but, on the other hand, the possibility that Hitler might come into possession of such bombs had to be reckoned with. Einstein, as the most influential scien tist in the world, was persuaded by Szilard to write a letter to President Franklin D. Roosevelt, urging him to put into effect a gigantic research program designed to develop a nuclear bomb. The result was the Manhattan Project, which, in six years, did develop such a bomb, the first being exploded at White Sands near Alamogordo, New Mexico, on July 16, 1945. By that time Hitler had been defeated, so the second and third bombs were exploded over Japan the next month. The nuclear bombs remained to threaten postwar mankind, and six coun tries—the United States, the Soviet Union, Great Britain, France, China, and India—now have such weapons. To the end of his life Einstein fought stub bornly for some world agreement to end the threat of nuclear warfare. He also expressed his strong opposition to the temporary aberration of McCarthyism that swept the United States in the early 1950s. His ability to revolutionize phys ics was greater, however, than his ability to change man’s heart, and at the time of his death the peril was greater than ever before. In death, he remained as unostentatious as in life. He was cre mated without ceremony and his ashes were scattered at some undisclosed place. Element number 99, discovered after his death, was named einsteinium in his honor, shortly after his death.
[1065] SCHMIDT
ro u s
[1065] SCHMIDT, Bernhard Voldemar Russian-German optician Born: Neissaar Island, Estonia, March 30, 1879 Died: Hamburg, Germany, De cember 1, 1935 Schmidt was bom at a time when Es tonia was part of the Russian empire (as it is of the USSR today). He lost his right arm in an accident when he was a boy and he received little schooling but succeeded in educating himself in optics. As telescopes grow larger, the field they can enlarge grows smaller. If one tries to keep the field both large and en larged, distortion creeps in about the edges. In 1930 Schmidt devised a special corrector plate, a small glass object with a complicated shape which could be placed near the focus of a spherical mir ror. The corrector plate bent the light waves in such a way as to eliminate dis tortion, and even wide fields could be en larged without distortion or aberration. An instrument outfitted with such a mirror and corrector plate is called a Schmidt telescope or a Schmidt camera. Used in conjunction with a conventional telescope it can guide the work of that telescope, for otherwise the astronomer would be looking at the heavens through a tiny peephole and large surveys would take up prohibitive amounts of time. Schmidt was an alcoholic who literally drank himself to death and whose last year of life was spent in a mental hospi tal. [1066] RICHARDSON, Sir Owen Willans English physicist Born: Dewsbury, Yorkshire, April 26, 1879 Died: Alton, Hampshire, Febru ary 15, 1959 After an education at Cambridge, Rich ardson, the son of a salesman of in dustrial tools, came to the United States in 1906 and remained at Princeton as a professor of physics in the years before World War I. ' During those years he studied how electrons and ions were given off by heated substances. It was because of this phenomenon that Edison [788] had been able to detect an electric current across a vacuum under certain conditions. The phenomenon had been used by John Fleming [803] to devise a rectifier and by De Forest [1017] to construct a triode. It was Richardson, though, who worked out the theory of electron and ion emission in detail and made possible the rapid improvement and development of radio tubes, television tubes, and so on. He was honored with the 1928 Nobel Prize in physics as a result. He had re turned to England in 1913 and there he taught at King’s College until 1944, then at the University of London until his re tirement. He was knighted in 1939. [1067] ROUS, Francis Peyton (rows) American physician
ber 5, 1879 Died: New York, New York, February 16, 1970 Rous studied at Johns Hopkins Uni versity and obtained his medical degree in 1905. In 1909 he joined the Rockefeller In stitute for Medical Research (now Rockefeller University) and almost at once a poultry breeder wandered in with a sick Plymouth Rock chicken that he wanted examined. It had a tumor and when it died, Rous, among other things, decided to test whether it might contain a virus. (He was sure it didn’t.) He mashed up the tumor and passed it through a filter that would keep out all infectious agents but viruses. He found, however, that this “cell-free filtrate” was infectious and would produce tumors in other chickens. He did not dare call it a virus in the report he published in 1911, but a quarter century later, when virus research began to explode with success, there was nothing else to call it. The “Rous chicken sarcoma virus” was the first of the “tumor viruses.” In 1966 he was awarded a share of the Nobel Prize for medicine and physiology 678 [1068] LAUE
LAUE [1068] for this work. The interval of fifty-five years between work and award set a rec ord, as did the age of the recipient— eighty-seven and still actively at work. Indeed, he remained at his desk till past his ninetieth birthday. [1068] LAUE, Max Theodor Felix von (low'uh) German physicist Born: Pfaffendorf (near Co blenz), Prussia, October 9, 1879 Died: Berlin, April 23, 1960 Laue, the son of an army official, spent his youth on the move as his fa ther’s assignments brought him to vari ous places. The schools he attended were many, but it was the high school at Strasbourg that crystallized his interest in science. He entered the University of Strasbourg in 1899 and devoted himself to theoretical physics. He obtained his doctor’s degree there in 1903 and in 1905 returned to the university as Planck’s [887] assistant, and between the two men a close friendship was es tablished. In 1909 Laue joined the faculty at the University of Munich, where he began his work on X rays. Since the discovery of X rays by Roentgen [774] in the pre vious decade, controversy had flourished as to the exact nature of the radiation. Some held it to consist of particles, as was true of cathode rays; some (includ ing Roentgen himself) opted for longitu dinal waves like those of sound; and some suggested that X rays were trans verse electromagnetic waves like those of light. The work of Barkla [1049] had made it almost certain that the third al ternative was the correct one. However, until the actual wavelength of X rays could be measured it was difficult to close the books. The wavelength of ordinary light could be measured by the extent of the diffraction of a particular monochro matic beam by a ruled grating in which the marks were separated by known dis tances. The shorter the wavelength of the light, the closer the grating had to be ruled for efficient determination. The trouble was that all the evidence in dicated that the wavelength of X rays was very much shorter than that of ordi nary light and in order to diffract the X rays, a grating would have to be ruled far more finely than the techniques then available could manage. It occurred to Laue that there was no need to manufacture such a grating. A crystal consisted of layers of atoms that were spaced just as regularly but far more closely than the ruled scratches of any man-made grating. A beam of X rays aimed at a crystal ought then to be diffracted as ordinary light would be by an ordinary grating. However, because the crystal had “lines” of atoms in vari ous directions, the results would be more complicated. There would be beams lo cated at varying distances and angles from the center, those distances and an gles depending on the structure of the crystal.
In 1912 having transferred to the Uni versity of Zürich in that year, Laue tried the experiment on a crystal of zinc sulfide and it worked perfectly. The pat tern was obtained and recorded on a photographic plate. It was the final point in favor of the electromagnetic view of X rays and the results were twofold. First, it offered a method of measuring the wavelengths of X rays by beginning with a crystal of known structure and measuring the amount of diffraction. (This the Braggs [922, 1141] accom plished almost at once.) Second, by using X rays of known wavelength it was possible to study the atomic structure of crystals, where such structure was un known. It could even, as it turned out, be used to study polymers, with their giant molecules showing the necessary internal regularities to diffract X rays. In 1953 such work reached a climax with Wilkins’ [1413] X-ray diffraction studies of nucleic acids. Laue was awarded the 1914 Nobel Prize in physics for his work. In 1919 he became professor of theoretical physics at the University of Berlin, a post he kept untü he resigned in 1943 in protest against the Nazis. (As early as 1939 he seized the occasion of a visit to Swit zerland to make his anti-Nazi stand 6 7 9
[1069] WOOLLEY
WEGENER [1071] plain, by denouncing Hitler’s policy of refusing to allow Germans to accept Nobel Prizes.) After the war he returned as director of the Max Planck Institute for Physical Chemistry. He died in an automobile accident in his eighty-first year. [1069] WOOLLEY, Sir Charles Leonard English archaeologist Born: London, April 17, 1880 Died: London, February 20, 1960
Woolley, the son of a minister, was educated at Oxford, and became an ar chaeologist, though that was not his first intention since he had been aiming at becoming a schoolmaster. He began digging in the Middle East as early as 1907 but work was inter rupted by World War I, of course, dur ing the course of which he served as an intelligence officer with the British army in Egypt. After the war, he began digging in Iraq (then under British control) and, particularly, at the site of the ancient Sumerian city of Ur, from which Abra ham (according to the Bible) had emi grated to Canaan. It was Woolley’s work, his uncovering of the artifacts of the earliest of the great civilizations (for it was the Sumerians who had been the first, shortly before 3000 b . c .,
to devise a system of writing), that placed Sumeria in the world’s consciousness during the 1920s.
It created a sensation greater than the world of archaeology had seen since the work of Schliemann [634] a half century before. This was particularly so because Woolley’s work cast light upon the Bible rather than upon the Iliad. He discov ered, for instance, geological evidence of a great flood, which had clearly given rise to the biblical tale of the Flood, though the real one had been confined to the Tigris-Euphrates Valley. In the 1930s and 1940s, he labored to uncover the relics of a Hurrian kingdom in northern Syria. He was knighted in 1935. [1070] GESELL, Arnold Lucius (geh- zel') American psychologist Bom: Alma, Wisconsin, June 21, 1880
Died: New Haven, Connecticut, May 29, 1961 Gesell’s mother was a schoolteacher. He graduated from the University of Wisconsin in 1903 and obtained his doc torate (in psychology) from Clark Uni versity in 1906. He joined the faculty of Yale University in 1911 (obtaining a medical degree from the university in 1915), and remained there for the rest of his life. He was interested at first in retarded children, but since retardation is a rela tive matter, he gradually grew interested in the mental development of children generally. Gesell and his group went into the matter in a large way, taking motion pictures of more than twelve thousand children. Their findings tended to show that children developed mentally in as set and orderly a pattern as they devel oped physically. It was easy to believe that the mental development followed closely the physical development of the nervous system, and the mind seemed more closely an aspect of the body and less a thing in itself. His books, describing his findings, have been extremely popular with par ents wishing to judge the relative prog ress of their offspring. [1071] WEGENER, Alfred Lothar (vay'- guh-ner) German geologist Bom: Berlin, November 1, 1880 Died: Greenland, November 1930 Wegener, the son of a director of an orphanage, obtained his Ph.D. in astron omy at the University of Berlin in 1905. Like Peary [866], he became a Green land specialist. He took part in four different expeditions to that Arctic is land, and died on the fourth. He was impressed, as others had been before him, by the similarity of the coast 680 [1071] WEGENER
LANGMUIR [1072] lines of South America and Africa. It is easy to imagine that the South American bulge on its east coast can just fit into the indentation on the west coast of Africa.
It also seemed that the New World and the Old World were drifting apart. At least, based on nineteenth-century longitude determinations, it would seem that Greenland (Wegener’s specialty) had moved a mile away from Europe in a century, that Paris and Washington were moving apart by fifteen feet each year, and that San Diego and Shanghai were approaching by six feet each year. In 1912 Wegener therefore proposed that originally the continents had formed a single mass (Pangaea or “All-earth”) surrounded by a continuous ocean (Panthalassa or “All-sea”). This large granite mass broke into chunks that slowly separated, floating on a basalt ocean, and, over hundreds of millions of years, took up the pattern of the frag mented continents we now have. In this fashion Wegener undertook to explain the changing pattern of glacia tions, for, of course, the relative posi tions of the poles with respect to the continents changed. He also used his hy pothesis to explain patterns of species similarities, wherein related species were found in widely separated parts of the world, and so on. It was quite a plausible theory and made converts. However, counterevi dence appeared. The apparent move ment of Greenland was found to be based on faulty determinations, and the better determinations of the twentieth century showed no movements of land masses at all. Nevertheless, additional evidence on the structure of the conti nental shelves, the nature of the mid oceanic rift, plus the discovery of a fossil amphibian in Antarctica have all worked to make “continental drift” more and more attractive to geologists. Wegener also took part in the contro versy over the lunar craters as to whether they arose through volcanic ac tion or through meteoric bombardment. He tried an ingenious experiment: drop ping powdered plaster onto a smooth layer of powdered cement. He was able to produce miniature replicas of lunar craters so faithfully that he all but con vinced astronomers that the meteoric hy pothesis was correct. [1072] LANGMUIR, Irving (lang'- myoor)
American chemist Bom: Brooklyn, New York, Jan uary 31, 1881 Died: Falmouth, Massachusetts, August 16, 1957 Langmuir, the son of an insurance ex ecutive, spent three years of his youth at school in Paris, then returned to the United States and graduated from Pratt Institute in 1898. He obtained a degree in metallurgical engineering at Columbia University in 1903, and in 1906 a Ph.D. in chemistry at the University of Got tingen in Germany, where he worked under Nernst [936]. After returning to the United States, Langmuir taught chemistry at the Stevens Institute of Technology and then joined the staff of the General Electric Company at Sche nectady, New York, in 1909. He re mained there until his retirement in 1950. At General Electric his first task was to extend the life of the light bulb, then very short. The tungsten filaments just coming into use were enclosed in vac uum. The presence of air would mean the rapid oxidation of tungsten once heated and it was thought that to lengthen the life one must improve the vacuum.
Langmuir’s studies, however, showed that in a vacuum, tungsten atoms slowly evaporated from the wire at the white- hot temperature of the glowing bulb. The wire grew thinner and eventually broke. The rate of evaporation was de creased in the presence of a gas—one, naturally, with which tungsten would not combine. Thereafter, light bulbs were filled with nitrogen (and, later, with the still less reactive argon) and lifetimes were multiplied. (Nevertheless, the in candescent bulb was not the end of prog ress in lighting, as Claude [989] was demonstrating in France.)
Download 17.33 Mb. Do'stlaringiz bilan baham: 
|