Leo Szilard: A prolific inventor

Szilard conceived the idea that it might be possible to break up atomic nuclei, releasing energy. He produced the first self- sustaining nuclear chain reaction in 1942. LEO SZILRD (pronounced Selaerd) was born on February 11, 1898 in Budapest (Hungary). He received his early education from his mother. He was a product of Hungarian higher education which nurtured creative spirit. He enrolled for electrical engineering at a polytechnic in Budapest. He was drafted into army to serve in Berlin. He changed in 1920 to study physics at the Berlin University where he received a doctorate degree in 1922.

His thesis, written under the supervision of the renowned theoretical physicist Max von Laue (Noble Laureate 1914) showed the academic potential of the Second Law of Thermodynamics, namely it not only covers the mean values of thermodynamic quantities but also governs the fluctuations around the mean values. He continued the work and showed in his paper 1929 the connection between entropy and information, paving way for modern cybernetic theory.

Szilard remained as Albert Einstein's assistant and then for five years till 1933 as "private dozent". He did research in nuclear physics at the Clarendon Laboratory. Here he conceived the idea that it might be possible to break up atomic nuclei, with the release of vast quantities of energy.

In 1938 Szilard moved to Columbia University, New York and then to Chicago University in 1942. After World War II he turned to theoretical biology, becoming in 1946 professor of biophysics at Chicago. In 1956, he shifted to the Salk Institute of Biological Sciences at La Jolla where he worked till the end of his life (May 30, 1964). His paper "On the Nature of the Aging Process" (1959) still stimulates research. His last paper "On Memory and Recall" was published posthumously.

During his Berlin period Szilard was granted 31 patents. The most famous among them is his 1934 patent for the idea of a nuclear chain reaction. This idea was extended to the well-known Einstein-Szilard pump for liquid metals, which also had no moving parts. The innovative idea was to use a varying magnetic field to induce a "ponderomotive force" on a closed current loop in the fluid conductor. Nowadays electromagnetic pump of this kind are used to circulate liquid sodium coolant in nuclear reactors (Physics Today October 2000.

At the Columbia University he demonstrate the release of neutrons in nuclear fissionIn January 1939, Szilard wrote prophetically "I knew that the world was headed for sorrow". With Fermi, he organised the research group at Chicago that produced the first self-sustaining nuclear chain reaction on December 2, 1942. The basic patent for the nuclear fission reactor was awarded jointly to Fermi and Szilard in 1945; but he never realised any financial profit from it. The last months of the World War found Szilard with James Franck engaged in a futile effort to convince President Truman against the use of atomic bomb as a legitimate war weapon against Japan.

Szilard became the crusading scientist bent on bringing to the American Congress fearful implications of nuclear war. In 1947 he propelled movement for the civilian control of atomic energy. He was one of the instigators and active participants in the international Pugwash Conference. He founded in 1962 the Council for a Livable World, a Washington lobby on nuclear arms control and policy issues.

R. Parthasarathy

Send this article to Friends by E-Mail

Section  : Science & Tech
Previous : Question Corner
Next     : Chemical significance of an arrow