1922 Encyclopædia Britannica/Einstein, Albert

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1922 Encyclopædia Britannica
Einstein, Albert
See also Albert Einstein on Wikipedia, and the disclaimer.

EINSTEIN, ALBERT (1879-       ), German-Swiss physicist, was born of Jewish parents at Ulm in the kingdom of Württemberg on May 14 1879. His boyhood was spent at Munich where his father, who owned electro-technical works, settled in the early ’eighties. The family migrated to Italy in 1894, whilst Albert Einstein went to the Cantonschule at Aarau in Switzerland, where he passed the abiturienten examination, the indispensable preliminary to any professional career in Central Europe, two years later. He attended lectures while supporting himself by teaching mathematics and physics at the polytechnic school at Zürich until 1900 and finally, after a year as tutor at Schaffhausen, was appointed examiner of patents at the patent office at Berne, where, having become a Swiss citizen, he remained until 1909. It was during this period that he took his Ph.D. degree at the university of Zürich and published his first papers on physical subjects. These were so highly thought of that in 1909 he was appointed extraordinary professor of theoretical physics at the university of Zürich. In 1911 he accepted the chair of physics in Prague, only to be induced to return to his own polytechnic school at Zürich as full professor in the following year. In 1914 his preëminence had become so evident that a special position was created for him in Berlin, where he was elected a member of the Royal Academy of Sciences and given a sufficient stipend to enable him to devote all his time to research without any restrictions or duties whatsoever. He was elected a foreign member of the Royal Society in 1921, having also been made previously a member of the Amsterdam and Copenhagen Academies, while the universities of Geneva, Manchester, Rostock and Princeton conferred honorary degrees on him.

Einstein's work is so important and has proved fertile in so many various branches of physics that it is not possible to do more than enumerate a few of the most salient papers. The work by which he is best known, the theory of relativity, was begun in 1905 with the publication of the restricted principle with its consequences (see Relativity). Though considered fantastic by many, it had secured fairly general acceptance in Germany in 1912, and was followed by the generalized theory in 1915. But Einstein's work has been by no means confined to such abstract questions. One of his earliest publications gave the complete theory and formulae of the phenomenon known as Brownian motion, which had puzzled physicists for nearly 80 years. He showed that the heat motion of particles, which is too small to be perceptible when these particles are large, and which cannot be observed in molecules since these themselves are too small, must be perceptible when the particles are just large enough to be visible and gave complete equations which enable the masses themselves to be deduced from the motions of these particles. Much of his time again was spent on the obscure problems usually combined under the heading “quantum theory.” The importance of these has become more and more evident, and the difficulty of reconciling the apparently inevitable discontinuities of the product of energy and time which experiment indicates, with our accepted habits of mind, always had a peculiar fascination for Einstein. Sooner probably than anybody else he realized the far-reaching implications of the theory propounded by Planck. His paper on the variation of the specific heat with temperature, which appeared in 1907, was the first extension of Planck's fuadamental hypothesis, and its verification in essentials is one of the most convincing arguments in its favour. Numerous other papers on molecular physics, including an experimental research on magnetism, appeared in the Proceedings of the Russian Academy of Science, the Physikalische Zeitschrift, the Proceedings of the German Physical Society, the Annalen der Physik, etc. (F. A. L.)