Saturday 29 October 2011

Andrei Sakharov

Andrei Dmitrievich Sakharov, Андре́й Дми́триевич Са́харов; May 21, 1921 – December 14, 1989 was a Soviet nuclear physicist, dissident and human rights activist. Earned renown as the designer of the Soviet Union's Third Idea, a codename for Soviet development of thermonuclear weapon; Sakharov was an advocate of civil liberties and civil reforms in the Soviet Union. He was awarded the Nobel Peace Prize in 1975, and is the namesake of the Sakharov Prize, which is awarded annually by the European Parliament for people and organizations dedicated to human rights and freedoms, is named in his honor.


Biography


Sakharov was born in Moscow on May 21, 1921. His father was Dmitri Ivanovich Sakharov, a private school physics teacher and an amateur pianist. His father later taught at the Second Moscow State University. Dmitri's grandfather Ivan had been a prominent lawyer in Tsarist Russia who had displayed respect for social awareness and humanitarian principles (including advocating the abolition of capital punishment) that would later influence his grandson. Sakharov's mother was Yekaterina Alekseyevna Sakharova (née Sofianos and of Greek ancestry). His parents and his paternal grandmother, Maria Petrovna, largely shaped Sakharov's personality. Although his paternal great-grandfather had been a priest in the Russian Orthodox Church, and his pious mother did have him baptised, his father was an atheist and religion did not play an important role in his life, though he did believe that a non-scientific "guiding principle" governed the universe and human life.




Education and career


Sakharov entered Moscow State University in 1938. Following evacuation in 1941 during the Great Patriotic War (World War II), he graduated in Aşgabat, in today's Turkmenistan. He was then assigned laboratory work in Ulyanovsk. During this period, in 1943, he married Klavdia Alekseyevna Vikhireva, with whom he raised two daughters and a son before she died in 1969. He returned to Moscow in 1945 to study at the Theoretical Department of FIAN (the Physical Institute of the Soviet Academy of Sciences). He received his Ph.D. in 1947.




Development of thermonuclear devices


After the end of World War II, Sakharov researched cosmic rays. In mid-1948 he participated in the Soviet atomic bomb project under Igor Kurchatov and Igor Tamm. The first Soviet atomic device was tested on August 29, 1949. After moving to Sarov in 1950, Sakharov played a key role in the development of the first megaton-range Soviet hydrogen bomb using a design known as "Sakharov's Third Idea" in Russia and the Teller-Ulam design in the United States. It was first tested as RDS-37 in 1955. A larger variation of the same design which Sakharov worked on was the 50MT Tsar Bomba of October 1961, which was the most powerful nuclear device ever exploded.
Sakharov saw “striking parallels” between his fate and those of J. Robert Oppenheimer and Edward Teller in the USA. While in the view of most American academics the two were as diametrically opposed as good and evil, Sakharov believed that in this “tragic confrontation of two outstanding people,” both deserved respect, because “each of them was certain he had right on his side and was morally obligated to go to the end in the name of truth.” While Sakharov strongly disagreed with Teller over nuclear testing in the atmosphere and Strategic Defense Initiative, he believed that American academics had been unfair to Teller’s resolve to get the H-bomb for the United States since “all steps by the Americans of a temporary or permanent rejection of developing thermonuclear weapons would have been seen either as a clever feint, or as the manifestation of stupidity. In both cases, the reaction would have been the same—avoid the trap and immediately take advantage of the enemy’s stupidity.”
Sakharov never felt that by creating nuclear weapons he had “known sin,” in Oppenheimer’s haunting expression. He later wrote: “After more than forty years, we have had no third world war, and the balance of nuclear terror ... may have helped to prevent one. But I am not at all sure of this; back then, in those long-gone years, the question didn’t even arise. What most troubles me now is the instability of the balance, the extreme peril of the current situation, the appalling waste of the arms race ... Each of us has a responsibility to think about this in global terms, with tolerance, trust, and candor, free from ideological dogmatism, parochial interests, or national egotism.”




Support for peaceful use of nuclear technology


In 1950 he also proposed an idea for a controlled nuclear fusion reactor, the tokamak, which is still the basis for the majority of work in the area. Sakharov, in association with Igor Tamm, proposed confining extremely hot ionized plasma by torus shaped magnetic fields for controlling thermonuclear fusion that led to the development of the tokamak device.




Efforts to improve nuclear reactor technology


In 1951 he invented and tested the first explosively pumped flux compression generators, compressing magnetic fields by explosives. He called these devices MC or MK (for magnetocumulative) generators. The radial MK-1 produced a pulsed magnetic field of 25 megagauss (2500 teslas). The following helical MK-2 generated 100 million amperes in 1953.
Sakharov then tested a MK-driven "plasma cannon" where a small aluminium ring was vaporized by huge eddy currents into a stable, self-confined toroidal plasmoid and was accelerated to 100 km/s. Sakharov later suggested to replace the copper coil in MK generators by a big superconductor solenoid to magnetically compress and focus underground nuclear explosions into a shaped charge effect. He theorized this could focus 1023 protons per second on a 1 mm2 surface, then envisaged to make two such beams collide. But it is not known if any experiment based on this idea has been ever achieved.




Research and physics


After 1965 Sakharov returned to fundamental science and began working on particle physics and cosmology.
He especially tried to explain the baryon asymmetry of the universe, being the first scientist to introduce two universes called "sheets", linked by the Big Bang. Sakharov achieved there a complete CPT symmetry since the second sheet is enantiomorph (P-symmetry), has an opposite arrow of time (T-symmetry) and is mainly populated by antimatter (C-symmetry) because of an opposite CP-violation. In this model the two universes do not interact, except via local matter accumulation whose density and pressure would become high enough to connect the two sheets through a bridge without spacetime between them, but with geodesics continuity beyond the radius limit allowing an exchange of matter. Sakharov called such singularities a collapse and an anticollapse, which are an alternative to the couple black hole and white hole in the wormhole theory. Sakharov also proposed the idea of induced gravity as an alternative theory of quantum gravity.




Turn to activism


From the late 1950s Sakharov had become concerned about the moral and political implications of his work. Politically active during the 1960s, Sakharov was against nuclear proliferation. Pushing for the end of atmospheric tests, he played a role in the 1963 Partial Test Ban Treaty, signed in Moscow.
The major turn in Sakharov’s political evolution started in 1967, when anti-ballistic missile defense became a key issue in US–Soviet relations. In a secret detailed letter to the Soviet leadership of July 21, 1967, Sakharov explains the need to "take the Americans at their word" and accept their proposal "for a bilateral rejection by the USA and the Soviet Union of the development of antiballistic missile defense", because otherwise an arms race in this new technology would increase the likelihood of nuclear war. He also asked permission to publish his manuscript (which accompanied the letter) in a newspaper to explain the dangers posed by this kind of defense. The government ignored his letter and refused to let him initiate a public discussion of ABM in the Soviet press.
In May 1968 he completed an essay, Reflections on Progress, Peaceful Coexistence, and Intellectual Freedom, where the anti-ballistic missile defense is featured as a major threat of world nuclear war. After this essay was circulated in samizdat and then published outside the Soviet Union (initially on July 6, 1968, in the Dutch newspaper Het Parool through intermediary of the Dutch academic and writer Karel van het Reve, followed by the New York Times), Sakharov was banned from all military-related research and returned to FIAN to study fundamental theoretical physics. In 1970 he, along with Valery Chalidze and Andrei Tverdokhlebov, was one of the founders of the Committee on Human Rights in the USSR and came under increasing pressure from the government. He married a fellow human rights activist, Yelena Bonner, in 1972.
In 1973 and 1974 the Soviet media campaign targeted both Andrei Sakharov and Aleksandr Solzhenitsyn. While Sakharov disagreed with Solzhenitsyn’s Slavophile vision of Russian revival, he deeply respected him for his courage. Only a few individuals in the Soviet Union dared to defend “traitors” like Sakharov and Solzhenitsyn, and those who had dared were inevitably punished.
Sakharov later described that “it took years” for him “to understand how much substitution, deceit, and lack of correspondence with reality there was” in the Soviet ideals. “At first I thought, despite everything that I saw with my own eyes, that the Soviet state was a breakthrough into the future, a kind of prototype for all countries”. Then he came, in his words, to “the theory of symmetry: all governments and regimes to a first approximation are bad, all peoples are oppressed, and all are threatened by common dangers.” After that he realized that there is not much “symmetry between a cancer cell and a normal one. Yet our state is similar to a cancer cell—with its messianism and expansionism, its totalitarian suppression of dissent, the authoritarian structure of power, with a total absence of public control in the most important decisions in domestic and foreign policy, a closed society that does not inform its citizens of anything substantial, closed to the outside world, without freedom of travel or the exchange of information.” Sakharov's ideas on social development led him to put forward the principle of human rights as a new basis of all politics. In his works he declared that "the principle 'what is not prohibited is allowed' should be understood literally", defying the unwritten ideological rules imposed by the Communist ruling elite on the society in spite of the seemingly democratic USSR Constitution.
In 1973 Andrei Sakharov was nominated for the Nobel Peace Prize and in 1974 was awarded the Prix mondial Cino Del Duca. He was awarded the Nobel Peace Prize in 1975, although he was not allowed to leave the Soviet Union to collect it. His wife read his speech at the ceremony in Oslo, Norway. The Norwegian Nobel Committee called him a spokesman for the conscience of mankind. In the words of the Nobel Committee’s citation: “In a convincing manner Sakharov has emphasised that Man’s inviolable rights provide the only safe foundation for genuine and enduring international cooperation.”
In no way did Sakharov consider himself a prophet or the like: “I am no volunteer priest of the idea, but simply a man with an unusual fate. I am against all kinds of self-immolation (for myself and for others, including the people closest to me).” In a letter written from his exile, he cheered up a fellow physicist and human rights activist with the words: “Fortunately, the future is unpredictable and also—because of quantum effects—uncertain.” For Sakharov the indeterminacy of the future supported his belief that he could, and should, take personal responsibility for it.


All about:  Moscow,   Russia,   Dmitry Medvedev,  Vladimir Putin

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