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25.01.2008 Alexander Alexandrovich Friedman
Category: Mathematics
(1888-1925)
Mathematician, geophysicist, cosmologist
THE EXPANDING UNIVERSE
In the spring of 1922, the prestigious "Physical journal" "Zeitschrift fur Physik "(namely, German journals at that time published the latest innovations in world science) published an appeal"To German physicists!".
The Board of the German Physical Society called on colleagues to save Russian physicists from a long term and cruel information famine: after all, since the beginning of the First World War, scientific journals have practically not been received in Russia.
It was proposed to send publications of recent years to the specified address.
Subsequently, they were planned to be sent to Petrograd.
In the same issue of the magazine — two dozen pages below — an article sent from Russia was published.
It was about Albert Einstein's general theory of relativity.
The author's name Alexander Friedman was unknown to German colleagues.
Alexander Fridman was born on June 16, 1888 in St. Petersburg in the family of Alexander Fridman, an artist of the corps de ballet of the Imperial St. Petersburg Theaters, and Lyudmila Volchek, a pianist, a graduate of the Conservatory.
Since childhood, the boy showed extraordinary abilities for the exact sciences.
Alexander was still a high school student when his mathematical talent attracted the attention of academician A. Markov, who advised the prodigy to enter physics, which, however, he himself was going to do.
In 1906, Alexander graduated from the Second St. Petersburg Gymnasium with a gold medal and became a student of the mathematical department of the Physics and Mathematics Faculty of St. Petersburg University.
During these years, Professor V. Steklov, a brilliant mathematician, a surprisingly bright personality, a future academician and vice president of the Russian Academy of Sciences, transferred to the capital from Kharkiv.
The Institute of Mathematics of the Russian Academy of Sciences now bears his name.
It was Vladimir Andreevich Steklov who was destined to become Alexander Fridman's Teacher, his reliable protection and support.
In 1910, A. Friedman and his friend Ya.
Tamarkin, on the recommendation of Professor Steklov, were left after graduation to prepare for a professorship.
The teacher wrote in his petition: "In terms of their abilities and hard work, both of these persons are equivalent and already at the present time they give the impression of young scientists, and not students who have just graduated from the university."
In 1922, Ya.
Tamarkin, a friend and co author of A. Friedman on several articles, illegally left Soviet Russia, moved to the United States and later taught at Cambridge.
After passing his master's exams in 1913, Friedman joined the main physical observatory, which was part of the Russian Academy of Sciences.
Alexander Alexandrovich then specialized in aerohydrodynamics, and such a "distribution" turned out to be very useful.
He was engaged in dynamic meteorology with inspiration, trying to describe in mathematical language those chaotic processes that occur in the atmosphere.
He described the weather with partial differential equations.
Then there was an internship at the University of Leipzig.
When the First World War began, Alexander Alexandrovich joined the volunteer aviation detachment.
He was engaged in the organization of aerological observations and the creation of a special aerological service on the Northern and Southwestern fronts, personally participated in reconnaissance operations, having learned to control an airplane.
A little later, Friedman was invited to teach at the school of aviators in Kiev.
Since 1917, he lectured at the Kiev University, then moved to Moscow and from there to Petrograd.
The war undermined the scientist's health.
He was diagnosed with a heart disease.
The doctors did not recommend the humid Petrograd climate to the patient.
And in November 1917, he applied for participation in a competition for the position of professor of the Department of Mechanics of Perm University.
Two people applied for one place: Professor A. Leibenzon and a private associate professor of the University of St. Petersburg.
Vladimir in Kiev, A. Friedman.
The University asked V. Steklov to give a review of the scientific work of the second of the applicants.
The following characteristic went to Perm: "It should be noted that G. Friedman is extremely efficient and has a general erudition not only in pure and applied mathematics, but also in many issues of theoretical mechanics, physics, meteorology...
I consider it very desirable to attract him as a teacher of mechanics at Perm University.
The university will find a worthy employee and scientific strength in him."
On April 13, 1918, Alexander Alexandrovich was elected to the post of extraordinary professor of the Department of Mechanics of Perm University.
From that day, the department actually began its history.
Due to the lack of teachers, the thirty year old professor had to take on courses in differential geometry and physics.
A deep study of these disciplines soon helped Friedman to get closer to the discovery of his life — the theory of the expansion of the Universe.
In May 1920, Alexander Alexandrovich took an academic leave and went to Petrograd.
In December, he finally resigned from his duties as a professor of mechanics at Perm University.
Peter attracted the scientist like a magnet, despite the prohibitions of doctors.
Friedman needed to communicate with his equals in intelligence, which he really lacked in Perm.
In Petrograd, fate brought Friedman together with Vsevolod Konstantinovich Friederiks.
This Russian physicist was caught by the First World War in an enemy power in Germany, and only the intercession of the outstanding mathematician David Hilbert saved him from a sad fate.
Friederiks was Hilbert's assistant at the University of Göttingen at the time when Einstein was constantly visiting there to discuss with Hilbert the main provisions of the general theory of relativity (GR) that he was creating.
Hilbert was one of the first to highly appreciate Einstein's theory of gravity, and Friederiks was present at this.
There were no serious publications on GRT that stirred up the entire physical world in post revolutionary Russia.
Only a few popular brochures on this topic have been published.
One of them was written by the author of the "theory of the century" — Albert Einstein.
Its Russian translation was published in 1920 in Berlin, and in the preface to it, the great scientist noted: "More than ever, in these troubled times, we should take care of everything that can bring people of different languages and nations closer together.
From this point of view, it is especially important to promote a lively exchange of artistic and scientific works even under the current difficult circumstances.
That's why I am especially pleased that my little book appears in Russian."
However, according to the popular statement of even Albert Einstein himself, it was impossible to master the general theory of relativity.
Friederiks filled in the gap.
In 1921, his presentation of GRT appeared in the journal "Successes of Physical Sciences".
This article helped Friedman a lot in working on his own theory.
For many centuries, humanity has considered the sky an ideal of stability and harmony, unattainable on a sinful Earth.
And even such a revolutionary in science as Einstein, who dared to fundamentally revise the age old physical concepts of space and time, did not dare to abandon the belief in the stationarity of the Universe.
Friedman, in his work "On the curvature of space", dared to assert that Einstein's general theory of relativity is a very special case.
The original Einstein solution to the cosmological problem likened the universe to a pendulum at rest.
With the help of GRT, the great physicist calculated the voltage in the "suspension rod".
Friedman also discovered that a suspended load does not necessarily have to be at rest, and using the equations of Einstein's theory, he calculated exactly what the movement should be.
In other words, having formulated and studied the cosmological problem in a more general case, Alexander Alexandrovich found that within the framework of Einstein's theory, it is essentially insoluble, more precisely, in the conceptual framework of the latter, it is possible to obtain a set of physically equal models of solutions, which does not allow making an unambiguous theoretical choice.
Friedman discovered that change is a generic property of the universe.
According to him, the constancy and positivity of the curvature in no way implies the finiteness of "our physical space occupied by shining stars".
According to Friedman, Einstein's field equations in their original form can be consistent with the cosmological principle and the assumption of a finite mass density in the universe only if space is not static.
It was a truly revolutionary idea.
Einstein himself did not accept it immediately.
He tried to "find" an error in the calculations of a Russian colleague.
And "found".
However, after receiving a letter from Friedman, in which he defended his correctness, Einstein called the results of his colleague "shedding light on the cosmological problem."
Here is what he wrote in the "Remarks to the work of A. Friedman" On the curvature of space "in 1922:" The results regarding the non stationary world contained in the mentioned work seem suspicious to me.
In fact, it turns out that the solution indicated in it does not satisfy the field equations."
On May 31, 1923, Einstein changed his opinion: "In a previous note, I criticized the above mentioned work, but my criticism, as I was convinced from Friedman's letter, was based on an error in calculations.
I think Friedman's results are correct and shed new light.
It turns out that the field equations admit, along with static ones, also dynamic (i.e., variables with respect to time) solutions for the structure of space."
Astronomers, however, did not pay attention to Friedman's theory until Edwin Hubble experimentally discovered the phenomenon of the expansion of the Universe and deduced the "speed—distance"relationship.
This happened seven years after the publication of the work of a Russian scientist, which indicated the presence of such a dependence.
Friedman himself was no longer alive by that time.
He died in 1925 at the age of 37 from typhoid fever.
Seven years later, the following entry appeared in V. Vernadsky's diary: "A conversation with Verigo about A. A. Friedman.
M. B., a brilliant scientist who died early, was described to me extremely highly by B. B. Golitsyn in 1915, and then I paid attention to him.
And now in connection with my current work and his idea of a spreading, pulsating Universe — I have read what is available to me.
A clear, deep thought of a widely educated, God given person.
According to V.— his comrade and friend, he was a charming person, a wonderful friend.
He met him at the front (Verigo in Kiev, Friedman aviator in Gatchina).
At the beginning of the Bolshevik power, Friedman and Tamarkin, his friend, but much lighter than him, were expelled from the University.
At one time, Friedman wanted to run away with T.
Maybe he would have stayed alive?"
Friedman was a mathematician who flashed like a bright star in the physical sky.
The equations he derived turned the density of matter to infinity, the radius of the universe to zero, and our world to one, the very first point.
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