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Men and Women of Science Albert Einstein Early Life Einstein was born in Ulm,
Germany on Mar. 14, 1879. Einstein's parents, who were non observant Jews, moved
from Ulm to Munich, Germany when Einstein was an infant. The family business was
the manufacture of electrical parts. When the business failed, in 1894, the
family moved to Milan, Italy. At this time Einstein decided officially to end
his German citizenship. Within a year, still without having completed secondary
school, Einstein failed an examination that would have allowed him to pursue a
course of study leading to a diploma as an electrical engineer at the Swiss
Federal Institute of Technology. He spent the next year in nearby Aarau at the
cantonal secondary school, where he enjoyed excellent teachers and first-rate
facilities in physics. Einstein returned in 1896 to the Swiss Federal Institute
of Technology, where he graduated, in 1900 as a secondary school teacher of
mathematics and physics.
After two years he obtained a post at the Swiss patent
office in Bern. The patent-office work required Einstein's careful attention,
but while employed (1902-1909) there, he completed an astonishing range of
publications in theoretical physics. For the most part these texts were written
in his spare time and without the benefit of close contact with either the
scientific literature or theoretician colleagues. Einstein submitted one of his
scientific papers to the University of Zurich to obtain a Ph.D. degree in 1905.
In 1908 he sent a second paper to the University of Bern and became a lecturer
there. The next year Einstein received a regular appointment as associate
professor of physics at the University of Zurich.
By 1909, Einstein was
recognized throughout German-speaking Europe as a leading scientific thinker. In
quick succession he held professorships at the German University of Prague and
at the Swiss Federal Institute of Technology. In 1914 he advanced to the most
prestigious and best-paying post that a theoretical physicist could hold in
central Europe, professor at the Kaiser-Wilhelm Gesellschaft in Berlin. The 1905
papers In the first of three papers that were published in 1905, Einstein
examined the phenomenon discovered by Max Planck, according to which
electromagnetic energy seemed to be emitted from radiating objects in quantities
that were ultimately discrete. The energy of these emitted quantities, the
so-called light-quanta was directly proportional to the frequency of the
radiation. This circumstance was perplexing because classical electromagnetic
theory, based on Maxwell's equations and the laws of thermodynamics, had assumed
that electromagnetic energy consisted of waves propagating in a hypothetical,
all-pervasive medium called the luminiferous ether, and that the waves could
contain any amount of energy no matter how small. Einstein used Planck's quantum
hypothesis to describe visible electromagnetic radiation, or light. According to
Einstein's resourceful viewpoint, light could be imagined to consist of discrete
bundles of radiation. Einstein used this interpretation to explain the
photoelectric effect, by which certain metals emit electrons when illuminated by
light with a given frequency. Einstein's theory, and his subsequent elaboration
of it, formed the basis for much of quantum mechanics. The second of Einstein's
1905 papers proposed what is today called the special theory of relativity. At
the time Einstein knew that, according to Hendrik Antoon Lorentz's theory of
electrons, the mass of an electron increased as the velocity of the electron
approached the velocity of light. Einstein also knew that the electron theory,
based on Maxwell's equations, carried along with it the assumption of a
luminiferous ether, but that attempts to detect the physical properties of the
ether had not succeeded. Einstein realized that the equations describing the
motion of an electron in fact could describe the nonaccelerated motion of any
particle or any suitably defined rigid body. He based his new kinematics on a
reinterpretation of the classical principle of relativity, that the laws of
physics had to have the same form in any frame of reference. As a second
fundamental hypothesis, Einstein assumed that the speed of light remained
constant in all frames of reference, as required by classical Maxwellian theory.
Einstein abandoned the hypothesis of the ether, for it played no role in his
kinematics or in his reinterpretation of Lorentz's theory of electrons. As a
consequence of his theory Einstein recovered the phenomenon of time dilatation,
wherein time, analogous to length and mass, is a function of the velocity of a
frame of reference. Later in 1905, Einstein elaborated how, in a certain manner
of speaking, mass and energy were equivalent.
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