Andrei Sakharov (1921-1989) was a Soviet physicist who became, in the words of the Nobel Peace Committee, a spokesman for the conscience of mankind. He was fascinated by fundamental physics and cosmology, but he had to spent two decades designing nuclear weapons. The acknowledged father of the Soviet hydrogen bomb, he contributed perhaps more than anyone else to the military might of the USSR. But it was his top secret experience as a leading nuclear expert that was instrumental in making Sakharov one of the most courageous critics of the Soviet regime, a human rights activist and the first Russian to win the Nobel Peace Prize. He helped bring down one of historyâ€™s most powerful dictatorships.
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