Pupin, Michael Idvorsky

PUPIN, MICHAEL IDVORSKY

(b. Idvor, Banat [now Yugoslavia], 4 October 1858; d. New York, N. Y., 12 March 1935)

applied physics.

Pupin was born to a family of unlettered Serbian settlers in the Banat, a military buffar zone between the Ottoman and Austro-Hungarian empires. Because of his obvious gifts, his parents were encouraged to let him complete his secondary studies at a larger center. He was thus sent to Prague, where he stayed for more than a year; but before he was sixteen, he went alone to America, arriving in New York in 1874. During the next five years he worked at odd jobs on farms and in factories, studying at night to prepare himself for admission to Columbia University on a scholarship, an ambition he fulfilled in 1879.

Pupin graduated with distinction in 1883 and after additional study at the University of Cambridge went to Berlin, where he worked under Helmholtz and G. Kirchhoff, receiving the doctorate in 1889 with a dissertation on osmotic pressure. He then returned to Columbia to teach mathematical physics in the newly formed department of electrical engineering. He advanced repidly and in 1901 was made professor of electromechanics, a post he occupied until his retirement in 1931.

During his studies of the distortions that arise when iron is magnetized by an alternating current, Pupin developed electrical resonators (by analogy with resonators used to study complex sound waves) that peoved to be applicable to problems in telegraphy and telephony. His most important contribution grew out of a study of the electrical analogue of a vibrating string “loaded” at regular intervals. This work not only confirmed that the periodic insertion of inductance coils in telephone lines would improve their performance by reducing attenuation and distortion, but it also allowed him to calculate optimum coil size and spacing, an invention of considerable practical and commercial value. For a time such lines were called “pupinized.”

Pupin also made many other contributions of an applied nature, for instance, in X-ray fluoroscopy, design of early radio transmitters, and electrical network theory. He was a popular and outstanding teacher. Among his pupils were several of the pioneers of radio communications, the most notable of whom was E. H. Armstrong. Pupin also became prominent in public affairs and was an adviser to the Yugoslav delegation to the Paris Peace Conference in 1919. He was an accomplished writer; and his best-selling autobiography, From Immigrant to Inventor, received the Pulitzer Prize in 1924. He received many honors, including eighteen honorary degrees, and was elected to the National Academy of Sciences.. The physics laboratory at Columbia University is named in his honor.

In 1888 Pupin married a young widow, Sarah Katherine Jackson; she died in 1896. The couple had one daughter, Varvara.

BIBLIOGRAPHY

Pupin’s publuications follow his entries in Poggendorff, VI, 2094; and Biographical Memoirs. National Academy of Sciences, 19 (1938), 307–232. The latter (by Bergen Davis) also lists his many honors and thirty-four patents. Other biographical entries include National Cyclopaedia of American Biography, XXVI (1937), 5–6; and Dictionary of American Biography, XXI, supp. 1 (1944), 611–615.

Charles SÜsskind