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KF5JRV > TODAY 14.03.19 13:23l 97 Lines 5458 Bytes #999 (0) @ WW
BID : 32729_KF5JRV
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Subj: Today in History - Mar 14
Path: IW8PGT<CX2SA<N3HYM<KF5JRV
Sent: 190314/1056Z 32729@KF5JRV.#NWAR.AR.USA.NA BPQ6.0.18
On March 14, 1879, Albert Einstein is born, the son of a Jewish
electrical engineer in Ulm, Germany. Einstein’s theories of special and
general relativity drastically altered man’s view of the universe, and
his work in particle and energy theory helped make possible quantum
mechanics and, ultimately, the atomic bomb.
After a childhood in Germany and Italy, Einstein studied physics and
mathematics at the Federal Polytechnic Academy in Zurich, Switzerland.
He became a Swiss citizen and in 1905 was awarded a Ph.D. from the
University of Zurich while working at the Swiss patent office in Bern.
That year, which historians of Einstein’s career call the annus
mirabilis–the “miracle yearö–he published five theoretical papers that
were to have a profound effect on the development of modern physics.
In the first of these, titled “On a Heuristic Viewpoint Concerning the
Production and Transformation of Light,ö Einstein theorized that light
is made up of individual quanta (photons) that demonstrate particle-like
properties while collectively behaving like a wave. The hypothesis, an
important step in the development of quantum theory, was arrived at
through Einstein’s examination of the photoelectric effect, a phenomenon
in which some solids emit electrically charged particles when struck by
light. This work would later earn him the 1921 Nobel Prize in Physics.
In the second paper, he devised a new method of counting and determining
the size of the atoms and molecules in a given space, and in the third
he offered a mathematical explanation for the constant erratic movement
of particles suspended in a fluid, known as Brownian motion. These two
papers provided indisputable evidence of the existence of atoms, which
at the time was still disputed by a few scientists.
Einstein’s fourth groundbreaking scientific work of 1905 addressed what
he termed his special theory of relativity. In special relativity, time
and space are not absolute, but relative to the motion of the observer.
Thus, two observers traveling at great speeds in regard to each other
would not necessarily observe simultaneous events in time at the same
moment, nor necessarily agree in their measurements of space. In
Einstein’s theory, the speed of light, which is the limiting speed of
any body having mass, is constant in all frames of reference. In the
fifth paper that year, an exploration of the mathematics of special
relativity, Einstein announced that mass and energy were equivalent and
could be calculated with an equation, E=mc2.
Although the public was not quick to embrace his revolutionary science,
Einstein was welcomed into the circle of Europe’s most eminent
physicists and given professorships in Zurich, Prague and Berlin. In
1916, he published “The Foundation of the General Theory of Relativity,ö
which proposed that gravity, as well as motion, can affect the intervals
of time and of space. According to Einstein, gravitation is not a force,
as Isaac Newton had argued, but a curved field in the space-time
continuum, created by the presence of mass. An object of very large
gravitational mass, such as the sun, would therefore appear to warp
space and time around it, which could be demonstrated by observing
starlight as it skirted the sun on its way to earth. In 1919,
astronomers studying a solar eclipse verified predictions Einstein made
in the general theory of relativity, and he became an overnight
celebrity. Later, other predictions of general relativity, such as a
shift in the orbit of the planet Mercury and the probable existence of
black holes, were confirmed by scientists.
During the next decade, Einstein made continued contributions to quantum
theory and began work on a unified field theory, which he hoped would
encompass quantum mechanics and his own relativity theory as a grand
explanation of the workings of the universe. As a world-renowned public
figure, he became increasingly political, taking up the cause of Zionism
and speaking out against militarism and rearmament. In his native
Germany, this made him an unpopular figure, and after Nazi leader Adolf
Hitler became chancellor of Germany in 1933 Einstein renounced his
German citizenship and left the country.
He later settled in the United States, where he accepted a post at the
Institute for Advanced Study in Princeton, New Jersey. He would remain
there for the rest of his life, working on his unified field theory and
relaxing by sailing on a local lake or playing his violin. He became an
American citizen in 1940.
In 1939, despite his lifelong pacifist beliefs, he agreed to write to
President Franklin D. Roosevelt on behalf of a group of scientists who
were concerned with American inaction in the field of atomic-weapons
research. Like the other scientists, he feared sole German possession of
such a weapon. He played no role, however, in the subsequent Manhattan
Project and later deplored the use of atomic bombs against Japan. After
the war, he called for the establishment of a world government that
would control nuclear technology and prevent future armed conflict.
In 1950, he published his unified field theory, which was quietly
criticized as a failure. A unified explanation of gravitation, subatomic
phenomena, and electromagnetism remains elusive today. Albert Einstein,
one of the most creative minds in human history, died in Princeton in
1955.
73 de Scott KF5JRV
Pmail: KF5JRV@KF5JRV.#NWAR.AR.USA.NA
email: KF5JRV@ICLOUD.COM
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