holy curiosity of inquiry; for what this delicate little plant needs more than anything,
besides stimulation, is freedom."
Einstein with his sister.
Einstein's family had moved to Italy to try to establish a business, and he joined
them for a glorious half year of freedom from work and anxiety. In 1895 he took
the entrance examination for the Swiss Federal Institute of Technology -- and he
failed. He was advised to study at a Swiss school in Aarau; here his teachers were
humane and his ideas were set free. His thoughts turned to the theory of
electromagnetism formulated by James Clerk Maxwell, seldom taught even in
universities at the turn of the century.
From a classroom essay Einstein wrote in French at the age of 16,
explaining why he would like to study theoretical mathematics or
physics: "Above all it is my individual disposition for abstract and
mathematical thought, my lack of imagination and practical talent. My
inclinations have also led me to this resolve. That is quite natural; one
always likes to do things for which one has talent. And then there is a
certain independence in the scientific profession which greatly pleases
me."
Einstein graduated from the Aarau school and entered the Institute of
Technology in Zurich. Around this time he recognized that physics was
his true subject. Only there could he "seek out the paths that led to the
depths." He also realized that he could never be an outstanding student.
Fortunately his friend Marcel Grossmann had the conventional traits
Einstein lacked. While Einstein worked in the library or the laboratory,
Grossmann took excellent notes at the mathematics lectures, and gladly
shared them with his friend before examinations. Einstein later wrote,
"I would rather not speculate on what would have become of me
without these notes."
Einstein grew familiar with the successes of past scientists who had tried to explain the world entirely through
atoms or fluids, interacting like parts of a machine. But he learned that Maxwell's theory of electricity and
magnetism was defying efforts to reduce it to mechanical processes. Through a new friend, the engineer
Michele Besso, Einstein came to the writings of Ernst Mach -- a skeptical critic of accepted ideas in physics.
"As a somewhat precocious young man, I was struck by the futility of the hopes and the
endeavors that most men chase restlessly throughout life. And I soon realized the cruelty of
that chase, which in those days was more carefully disguised with hypocrisy and glittering
words than it is today."
After Einstein graduated with an undistinguished record, he made a number of efforts to get a university job,
and failed. He found only occasional jobs on the periphery of the academic world. He felt he was a burden on
his none too prosperous family, and wondered if he had been mistaken in trying to become a physicist. Finally
he got a position at the Swiss Patent Office in Bern. It was "a kind of salvation," he said. The regular salary
and the stimulating work evaluating patent claims freed Einstein. He now had time to devote his thought to
the most basic problems of physics of his time, and began to publish scientific papers.
Einstein's closest friend, with whom he walked home from the Patent
Office every day, was Michele Besso. Einstein thought him "the best
sounding board in Europe" for scientific ideas. With other friends in
Bern, all unknown to the academic world, Einstein met regularly to read
and discuss books on science and philosophy. They called themselves the
Olympia Academy, mocking the official bodies that dominated science.
Einstein's began to attract respect with his published papers (described in
the next section), and in 1909 he was appointed associate professor at the
University of Zurich. He was also invited to present his theories before
the annual convention of German scientists. He met many people he had
known only through their writings, such as the physicist Max Planck of
Berlin. Soon Einstein was invited to the German University in Prague as
full professor. Here he met a visiting Austrian physicist, Paul Ehrenfest.
"Within a few hours we were true friends," Einstein recalled, "as though
our dreams and aspirations were made for each other.”
At the Zurich Polytechnic a romance had arisen between the handsome
and witty would-be science teacher and a young Serbian woman, Mileva
Maric, the only woman in Albert's physics class. Einstein's family
opposed any talk of marriage, even after Mileva gave birth to a daughter
(who was apparently given up for adoption). The pair finally married in
1903 after Einstein got his job at the Patent Office. Einstein discussed
physics with Mileva, but there is no solid evidence that she made any
significant contribution to his work. In 1904 a son was born, and a
second in 1910.
Through letters, visits, and science meetings, Einstein came to know
most of the major physicists of Europe (there were not many in those
days). In 1912 Einstein was invited back to the Swiss Federal Institute of
Technology as professor. Here he rejoined his old friend Marcel
Grossmann, now professor of mathematics. With Grossmann's aid,
Einstein studied the mathematical theories and techniques which he
found necessary for his work toward a new theory of gravitation.
Meanwhile, Einstein was being introduced to a different sort of world by
another friend, Friedrich Adler: the world of the Second International and
its attempt to halt the growth of international rivalries in Europe.
In 1914, the German government gave Einstein a senior research appointment in Berlin, along with a
membership in the prestigious Prussian Academy of Sciences. When Einstein had left his native land as a
youth, he had renounced German citizenship and all of the militarist German society. But Berlin -- with no
teaching duties and a galaxy of top scientists for colleagues -- could not be resisted. It was the highest level a
scientific career could ordinarily reach.
"With such fame, not much time remains for his wife," Mileva complained. "I am very starved for love."
Einstein felt suffocated in the increasingly strained and gloomy relationship. He found solace in a love affair
with his cousin, Elsa Löwenthal. Mileva and Albert separated in 1914, after bitter arguments, and divorced in
1919. That same year he married Elsa, and settled in with her and her two grown daughters by a previous
marriage. "The Lord has put into him so much that's beautiful, and I find him wonderful," Elsa later wrote,
"even though life at his side is enervating and difficult."
"A storm broke loose in my mind."
MARCH 1905
Einstein sent to the Annalen der Physik, the leading German physics journal, a
paper with a new understanding of the structure of light. He argued that light
can act as though it consists of discrete, independent particles of energy, in
some ways like the particles of a gas. A few years before, Max Planck's work
had contained the first suggestion of a discreteness in energy, but Einstein
went far beyond this. His revolutionary proposal seemed to contradict the
universally accepted theory that light consists of smoothly oscillating
electromagnetic waves. But Einstein showed that light quanta, as he called the
particles of energy, could help to explain phenomena being studied by
experimental physicists. For example, he made clear how light ejects
electrons from metals.
The Annalen der Physik received another paper from Einstein. The wellknown
kinetic energy theory explained heat as an effect of the ceaseless
agitated motion of atoms; Einstein proposed a way to put the theory to a
new and crucial experimental test. If tiny but visible particles were
suspended in a liquid, he said, the irregular bombardment by the liquid's
invisible atoms should cause the suspended particles to carry out a random
jittering dance. Just such a random dance of microscopic particles had long
since been observed by biologists (It was called "Brownian motion," an
unsolved mystery). Now Einstein had explained the motion in detail. He had
reinforced the kinetic theory, and he had created a powerful new tool for
studying the movement of atoms.
"When the Special Theory of Relativity began to germinate in me, I was visited by all sorts
of nervous conflicts... I used to go away for weeks in a state of confusion."
Einstein sent the Annalen der Physik a paper on electromagnetism and
motion. Since the time of Galileo and Newton, physicists had known that
laboratory measurements of mechanical processes could never show any
difference between an apparatus at rest and an apparatus moving at constant
speed in a straight line. Objects behave the same way on a uniformly moving
ship as on a ship at the dock; this is called the Principle of Relativity. But
according to the electromagnetic theory, developed by Maxwell and refined
by Lorentz, light should not obey this principle. Their electromagnetic theory
predicted that measurements on the velocity of light would show the effects of
motion. Yet no such effect had been detected in any of the ingenious and
delicate experiments that physicists had devised: the velocity of light did not
vary.
Einstein had long been convinced that the Principle of Relativity must apply
to all phenomena, mechanical or not. Now he found a way to show that this
principle was compatible with electromagnetic theory after all. As Einstein
later remarked, reconciling these seemingly incompatible ideas required
"only" a new and more careful consideration of the concept of time. His new
theory, later called the special theory of relativity, was based on a novel
analysis of space and time -- an analysis so clear and revealing that it can be
understood by beginning science students.
Einstein reported a remarkable consequence of his special theory of relativity:
if a body emits a certain amount of energy, then the mass of that body must
decrease by a proportionate amount. Meanwhile he wrote a friend, "The
relativity principle in connection with the Maxwell equations demands that
the mass is a direct measure for the energy contained in bodies; light transfers
mass... This thought is amusing and infectious, but I cannot possibly know
whether the good Lord does not laugh at it and has led me up the garden
path." Einstein and many others were soon convinced of its truth. The
relationship is expressed as an equation: E=mc2.
will continue later........
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