Leo szilard
Leó Szilárd (February 11, 1898, Budapest - May 30, 1964, La Jolla, California) was a Hungarian-American Jewish physicist who worked on the Manhattan Project. the importance of his work in nuclear physics and later in molecular biology, he is also known for being the author of the letter (also signed by Albert Einstein) addressed to the president of the United States Franklin D. Roosevelt in August 1939, which led to the development of the atomic bombs dropped on Hiroshima and Nagasaki in 1945.
Semblance
Early Years
Leo Spitz was born in Budapest, in what was then the Kingdom of Hungary, on February 11, 1898. His parents, middle-class and of Jewish origin, the civil engineer Louis Spitz and Tekla Vidor, raised him in the neighborhood from Fasor Városligeti from the city of Pest. He had two younger brothers, Béla, born in 1900, and his sister Rózsi (Rose), born in 1901. On October 4, 1900, the family changed their surname from German &# 34;Spitz" from Hungarian "Szilard", a name meaning "solid" in Hungarian. Despite having a religious background, Szilard became an agnostic. From 1908 to 1916 he attended the secondary school 'Reáliskola' in Hungary. in his hometown. Showing an early interest in physics and great ability in mathematics, in 1916 he won the Eötvös Prize, a national prize for mathematics.
In the midst of World War I in Europe, Szilard received the news on January 22, 1916 that he had been drafted into the 5th Fortress Regiment, but was able to continue his studies. He enrolled as an engineering student at the Budapest University of Technology and Economics, entering in September 1916. The following year he joined the 4th Mountain Artillery Regiment of the Austro-Hungarian army, but was immediately sent to Budapest as a candidate for official. He rejoined his regiment in May 1918, but in September, before being sent to the front, he fell ill with the 1918 influenza pandemic and returned home to be hospitalized. He was later informed that his regiment he had been nearly wiped out in combat, so the disease probably saved his life. He was honorably discharged in November 1918, after the end of the war.
In January 1919, Szilard resumed his engineering studies, but Hungary was in a chaotic political situation under the rule of the Hungarian Soviet Republic under Béla Kun. Szilard and his brother Béla founded their own political group, the Hungarian Association of Socialist Students, with a platform based on a tax reform scheme devised by Szilard. He was convinced that socialism was the answer to Hungary's postwar problems, but not that of Kun's Hungarian Socialist Party, which had close ties to the Soviet Union. When Kun's government faltered, the brothers officially changed their religion of "Israelite" to "Calvinist," but when they tried to re-enroll at what was now the Budapest University of Technology, nationalist students prevented them because of their Jewish status.
Convinced that there was no future for him in Hungary, Szilard left for Berlin via Austria on December 25, 1919, and enrolled at the Technical University of Berlin. Soon his brother Béla joined him.Szilard became bored with engineering, and his attention turned to physics. This discipline was not taught at the Technische Hochschule, so it was transferred to the Guillermo Federico University, where he attended lectures given by Albert Einstein, Max Planck, Walther Nernst, James Franck and Max von Laue. He also met with his fellow Hungarian students Eugene Paul Wigner, John von Neumann and Dennis Gabor. His doctoral thesis in thermodynamics, Über die thermodynamischen Schwankungserscheinungen (On the manifestation of thermodynamic fluctuations), was praised by Einstein, and won top honors in 1922. The thesis dealt with an old problem in the philosophy of thermal physics and statistics, known as Maxwell's Demon, a thought experiment conceived by physicist James Clerk Maxwell. The problem was thought to be unsolvable, but in tackling it, Szilard recognized the connection between thermodynamics and information theory.
Szilard was appointed as von Laue's assistant at the Institute for Theoretical Physics in 1924. In 1927 he finished his habilitation and became a Privatdozent (private professor) of physics. For his habilitation lecture, he produced a second paper on Maxwell's demon, Über die Entropieverminderung in einem thermodynamischen System bei Eingriffen intelligenter Wesen (On the reduction of entropy in a thermodynamic system by the intervention of intelligent beings), which had actually been written shortly after the first. In this writing he introduced the thought experiment now known as Szilard's machine, an important milestone in the history of attempts to understand Maxwell's demon problem. The paper is also the first equation on negative entropy and information. As such, he placed Szilard as one of the founders of information theory, but he did not publish it until 1929, and he did not follow it up. Claude Elwood Shannon, who took it up in the 1950s, recognized Szilard's publication as his starting point.
While in Berlin, Szilard worked on numerous technical inventions. In 1928 he applied for a patent for a linear accelerator, unaware of an earlier article by Gustav Ising in a 1924 magazine, nor of Rolf Widerøe's operating device, and in 1929 he applied for one for the cyclotron. He also conceived of an electron microscope. Between 1926 and 1930, he worked with Einstein to develop Einstein's refrigerator, notable for having no moving parts. He did not build any of these devices, nor did he publish these ideas in scientific journals, so credit of these ideas often went to others. As a result, Szilard never received the Nobel Prize, but Ernest Lawrence was awarded for the cyclotron in 1939 and Ernst Ruska for the electron microscope in 1986.
English and American stages
Szilard received German citizenship in 1930, but was already uneasy about the political situation in Europe. When Adolf Hitler became Chancellor of Germany on January 30, 1933, Szilard urged his family and friends to flee Germany. Europe while they still could. He moved to England, helping to found the Academic Assistance Council, an organization dedicated to helping refugee scholars find new jobs, and convinced the Royal Society to provide accommodation at Burlington House, for which he was assisted by scholars such as Harald Bohr, Godfrey Harold Hardy, Archibald Vivian Hill and Frederick G. Donnan. At the outbreak of World War II in 1939, he had helped find employment for more than 2,500 refugee students.
In London, he read an article written by Rutherford in The Times, after which he conceived the idea of a nuclear chain reaction. Szilard was probably the first scientist to seriously think about building atomic bombs. (He had read the fictional account & # 34; atomic bombs & # 34; within the science fiction novel by H. G. Wells The World Set Free ). He thought about the possibility of a nuclear chain reaction on September 12, 1933 while waiting to cross the road on Southampton Avenue in Bloomsbury. Szilárd reportedly had this idea as a result of his anger at Ernest Rutherford's refusal to talk about nuclear power. Szilárd was also the co-owner, along with Enrico Fermi, of the patent on the nuclear reactor. Over the next year, he applied for a patent on the nuclear chain reaction. He first tried to create this chain reaction using beryllium and indium, but he didn't get the reaction he expected. In 1936, he assigned the chain reaction patent to the British Admiralty to ensure the secrecy of the patent.
In 1938, he accepted an offer to head research at Columbia University in Manhattan, and moved to New York. There he worked alongside Nobel Prize winner Enrico Fermi. After studying fission in 1939, he concluded that uranium would be the element capable of producing the chain reaction.
Szilárd was instrumental in developing the Manhattan Project. He sent a confidential letter to Franklin D. Roosevelt explaining this possibility, and encouraging the development of this program, and obtained the endorsement of Albert Einstein in August 1939. Later, he transferred to the University of Chicago to continue working on the development. of the bomb. There, with Fermi, he collaborated in the construction of the first "neutron reactor", a pile of uranium and graphite with which the first autonomous nuclear chain reaction was obtained in 1942.
As the war continued, Szilárd became increasingly upset that he was being forced to turn over the direction of his scientific experiments to the military, and he clashed numerous times with General Leslie Groves, the military chief of the Project. Manhattan. His resentment towards the US government increased due to its failed attempt to prevent the use of the atomic bomb in war.
Survivor of the "shipwreck" From Hungary after World War I, having suffered all kinds of oppressions, Szilárd had a passion for the preservation of human life and freedom, especially the freedom to communicate ideas. He hoped that the US government, which before the war was opposed to the bombing of civilians, would not use the bomb, since the only possible objective of a weapon of this magnitude is precisely to kill civilians. He hoped that the mere threat of the bomb would force Germany or Japan to surrender. Rather than threaten the Axis with the bomb, Harry Truman decided to simply use it, despite the protests of Szilárd and many other project scientists, killing an estimated 300,000 Japanese civilians and totally destroying Hiroshima and partially destroying Nagasaki.
In 1943, he became a citizen of the United States.
In 1947, he switched from physics to molecular biology, working extensively with Aaron Novick. He spent his last years at the Salk Institute in San Diego. He founded the Council for a Livable World in 1962 to bring "the sweet voice of reason" to the world. on nuclear weapons to Congress, the White House, and the American public.
He died in his sleep of a heart attack in 1964. He was known to his colleagues as a quick-thinking, eccentric thinker, "so good and caring he scared people away" with strange and seemingly incongruous, but extremely insightful statements.
Eponymy
- The lunar crater Szilard carries this name in his memory.
- The asteroid (38442) Szilárd also commemorates its name.