Lemaitre, Georges, << luh meht ruh, zhawrzh >> (1894-1966), was a Belgian astrophysicist and cosmologist who developed an early version of what came to be called the big bang theory of the universe. An astrophysicist is a scientist who applies principles of physics to astronomy. A cosmologist studies the structure and development of the universe. The big bang theory is the most widely accepted theory of the origin of the universe. According to this theory, the universe began as a hot, explosive event—a “big bang”—about 10 billion to 20 billion years ago. The Russian-born American physicist George Gamow later developed Lemaitre’s original work (see Gamow, George ).
Georges Henri Lemaitre was born on July 17, 1894, in Charleroi, Belgium. He studied mathematics and physics at the University of Louvain, Belgium, and received his doctorate in 1920. In 1923, Lemaitre was ordained as a Roman Catholic priest. Between 1923 and 1927, he worked at Cambridge University in the United Kingdom and at Harvard University and Massachusetts Institute of Technology in the United States. In 1927, he became a professor of astrophysics at the University of Louvain in Belgium.
In 1927, Lemaitre completed his first scientific paper on the expansion of the universe. Astronomers had observed that the galaxies are moving away from each other. Lemaitre said that, in earlier times, the galaxies would have been closer to each other than at present. He concluded that there must have been a moment when the whole universe was condensed in the form of a “primeval atom.” The explosion of that atom began the expansion of the universe, according to Lemaitre. With this theory, Lemaitre gained recognition as a leading figure in cosmology.
In 1941, Lemaitre was elected a member of the Belgian Royal Academy of Science and Fine Arts. His many awards included the Eddington Medal of the Royal Astronomical Society in the United Kingdom, received in 1953. In 1960, he became the president of the Pontifical Academy of Sciences in Vatican City. He died in Louvain on June 20, 1966. His publications include Discussion on the Evolution of the Universe (1933) and Hypothesis of the Primeval Atom (1946).
See also Astronomy (Developing the modern view) ; Big bang ; Cosmology ; Galaxy (Galaxy evolution) .
