The Life of Alexander Friedmann
Alexander Friedmann was born on June 16, 1888 in Saint
Petersburg, Russia. He was born to a ballet dancer and pianist. Early on his
life, he witnessed the separation of his parents’ marriage. Thus growing up, he
lived with his father. In 1897, Friedmann attended Second St Petersburg
Gymnasium where he initially had a standard academic standing. Although, before
long, he became one of the top students. Included amongst the top academic
students, was Alexander’s friend Yakov Tamarkin. The two remained friends
throughout school and university. As mathematicians, in 1905, Friedmann and
Tamarkin wrote about Bernoulli numbers and in 1906 it was published in
Mathematische Annalen. During this year, Friedmann and Tamarkin became
interested in politics. This was evident in his participation as a leader of
strikes at school and protested the government’s oppression for education. Following
his graduation, in 1906, Friedmann enrolled in the University of St Petersburg
later that year. During his time at the university, he had the opportunity to
participate in a seminar on physics in 1907. It was organized by Ehrenfest and
the topics discussed are quantum theory, statistical mechanics, and relativity.
After completing his undergraduate degree in 1910, Friedmann continued his
studies to obtain a graduate degree. After receiving the degree in 1913,
Friedmann was hired by the Aerological Observatory in Pavlovsk. His position
required him to study meteorology. Following this, in 1914, Friedmann travelled
to Leipzig to study with the well-known meteorologist, Vilhelm Bjerknes. That
same year, World War I began and Friedmann voluntarily joined and became a
pilot of the Russian Air Force. During the war, he remained passionate about
mathematics and shared this thoughts with Steklov by writing letters. In addition,
it was at this time when Friedmann received the award, George Cross for his courage.
He was then sent to Kiev in 1915 and was employed as the head of the Central
Aeronautical Station. In 1917, the Central Aeronautical Station was relocated to
Moscow and Alexander decided to move as well. After being stopped to work here,
Friedman became a professor at the University of Perm. He was a part of both
the Department of Mathematics and Department Physics and founded an Institute
of Mechanics at the university. Additionally, Friedmann was a part of the Journal
as an editor for the Physics-Mathematical Society of University of Perm. As a
result of the civil war, he went back to St Petersburg and worked at the Main
Geophysical Observatory. Later, Friedmann took several other positions related
to his field of expertise. These include, professor in Petrograd University,
teaching mechanics, physics and mathematics meanwhile worked at the same Institute
of Railway Engineering, and the Naval Academy and researched at the Optical
Institute. Near the end of his life, Friedmann constructed a remarkable balloon
flight in order to make observations. Near the end of August in 1925, he was detected
to have typhoid and within two weeks of being hospitalized, Friedmann passed
away.
Cosmological Works: Einstein and
Three Types of Universe Models
Albert Einstein in his paper on the General Relativity,
believed in the theory that the universe was in fact static. Einstein had incorporated
the cosmological constant into his calculations to account for the static model
of the universe. This cosmological constant was viewed to him as a repulsive
force in the universe that kept the universe from collapsing within itself. Alexander
Friedmann had confronted the use of the static universe model that was accepted
by many scientists at the time along with Einstein. He proposed substituting the
cosmological constant with other values and developed different models of the
universe, these models that he proposed were dynamic in nature. Friedmann
proposed three models of the universe closed, open, and Einstein-deSitter. The
first closed model of the universe proposed that the universe was expanding. At
a point in time this model of the universe will stop expanding and eventually
collapse on itself. The closed model is represented as a spherical universe and
is assumed to have a high density. Another model proposed was the Open Model of
the universe. In this model the universe is expanding and will continue to
expand forever. The open model is assumed to have a low density. The third
model, Einstein-deSitter was a combination of both the closed and open models
of the universe. In this model it was theorized that the universe will expand
to a point then collapse on itself but never fully expand or collapse. All the
models that Friedmann presented had one thing in common, which was that the
universe was not static. This proposal lead on to many advancements in the
study of cosmology. After the publication of Friedmann’s theory, many
scientists opposed his findings. Albert Einstein had responded to Friedmanns
work and stated that there must be miscalculations in his work. Friedmann replied
to Einstein’s statement by sending him a detailed letter including extensive
calculations explaining his theory. Friedmann requested Einstein to retract his
prior statement if Einstein could discredit his calculations. When Einstein
later read this letter, he accepted Friedmann’s theory and revised his
statement by accepting Friedmann’s work. Einstein eventually removed the
cosmological constant and credited Friedmann for his contribution towards
General Relativity.
George Gamow: Friedmann’s Student
At Friedmann’s time working at the University of St.
Petersburg, he had a student named George Gamow. Gamow was also born in Russia
in 1904 and is recognized as a cosmologist, nuclear and theoretical physicist.
He known for his work contributing to radioactivity and was working on his own
theory. His biggest contribution to his field of study was his theory about the
alpha particle decay of atomic nuclei. In 1948, George Gamow with his colleague
Ralph Alpher published “The Origins of Chemical Elements”. In this paper they
pointed out that the current universe is the aftermath of the chemical
reactions that occurred during the Big Bang, and the composition of hydrogen
and helium in the universe can be accounted for in their theory. Additionally Gamow
had estimated the strength of the cosmic microwave background radiation. He
predicted that the Big Bang would have resulted in an afterglow that would cool
down billions of years later and fill the universe with radiation that was
approximately 5 degrees above absolute zero. George Gamow’s theory was the
foundation for further scientific contributions from other advocates of the Big
Bang theory. In the year 1965 in America, Arno Penzias and Robert Wilson accidently
found the existence of cosmic microwave background. They determined that its
temperature was approximately 2.7K, as a result proving Gamow’s theory.
References
George Gamow - Important Scientists - The Physics of the
Universe. (n.d.). Retrieved March 25, 2015, from http://www.physicsoftheuniverse.com/scientists_gamow.html
Alexander Friedmann: Unsung Hero of Modern Cosmology. (2012,
October 31). Retrieved March 25, 2015, from http://www.decodedscience.com/alexander-friedmann-unsung-hero-of-modern-cosmology/19423
Alexander Friedmann - Important Scientists - The Physics of
the Universe. (n.d.). Retrieved March 25, 2015, from http://www.physicsoftheuniverse.com/scientists_friedmann.html
Aleksandr Aleksandrovich Friedmann. (n.d.). Retrieved March
25, 2015, from http://www-history.mcs.st-and.ac.uk/Biographies/Friedmann.html
The Friedmann Equation for the Expanding Universe. (n.d.).
Retrieved March 25, 2015, from http://www.einsteins-theory-of-relativity-4engineers.com/friedmann-equation.html
http://friedmannlab.ru/Img/friedmann.jpg
http://phys.colorado.edu/sites/default/files/gamowmain.jpg
http://www.phys-astro.sonoma.edu/PEOPLE/FACULTY/TENN/FriedmannModels.jpg
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