|Georges Lemaître (1894-1966)|
On June 20, 1966, Belgian priest, astronomer and professor of physics Georges Lemaître passed away. He was the first person to propose the theory of the expansion of the Universe, widely misattributed to Edwin Hubble, and is best known for his proposal of what became known as the Big Bang theory of the origin of the Universe.
Maybe, if you are interested in astronomy, you might have heard about famous astronomer Edwin Hubble and the theory of the expanding universe. But even I didn’t know that Hubble adapted his theory from the original ideas of George Lemaître. But, who was this Belgian priest with these profound insights about our universe? George Lemaître was born on July 17, 1894 in the Belgian town of Charleroi. After a classical education at the Collège du Sacré-Coeur, a Jesuit secondary school, he began studying civil engineering at the Catholic University of Leuven at the age of 17. In 1914, he interrupted his studies to serve as an artillery officer in the Belgian army at World War I, where he received the Belgian War Cross with palms. After the war, he studied physics and mathematics, and began to prepare for priesthood, obtaining his PhD in 1920. In 1923, he was ordained a priest.
In 1923, he became a graduate student in astronomy at the University of Cambridge, working with Arthur Eddington who initiated him into modern cosmology, stellar astronomy, and numerical analysis. After spending a year at Harvard College Observatory in Cambridge and at the Massachusetts Institute of Technology, he returned to Belgium in 1925, where he became a part-time lecturer at the Catholic University of Louvain. There he worked on the publication of his most famous paper “A homogeneous Universe of constant mass and growing radius accounting for the radial velocity of extragalactic nebulae”, where he presented his new idea of an expanding Universe. Actually, he also derived Hubble’s law and provided the first observational estimation of the Hubble constant. But, when the universe is expanding, how did it begin its expansion and what was its initial size? Up to this point in time, Lemaître supposed the initial state as a finite-size static universe based on Einstein’s model. Unfortunately, the paper had little impact because it was not widely read by astronomers outside of Belgium. Even after translating the paper into English with the help of Arthur Eddington, for some unknown reasons the part with the Hubble constant didn’t occur in the English version.
Finally, after Eddington published a paper commenting Lemaître’s work as being a “brilliant solution” to the outstanding problems of cosmology, Lemaître was invited to London, where he proposed that the Universe expanded from an initial point, which he called the “Primeval Atom” and developed in a report published in Nature. Lemaître himself also described his theory as “the Cosmic Egg exploding at the moment of the creation”, but it became better known as the “Big Bang theory” a pejorative term coined by Fred Hoyle who was a proponent of the steady state universe. Lemaître’s proposal met skepticism from his fellow scientists at the time. Eddington found it unpleasant, while Albert Einstein found it suspect because he deemed it unjustifiable from a physical point of view. But, when Einstein and Lemaître met at a series of conferences and seminars, where Lemaître found sufficient time to explain his ideas in sufficient detail, it is reported that Einstein stood up, applauded, and said, “This is the most beautiful and satisfactory explanation of creation to which I have ever listened.”
Lemaître received various honors and prizes for his scientific work, as e.g., the Francqui Prize, the highest Belgian scientific distinction. In 1936, he was elected member of the Pontifical Academy of Sciences. He took an active role there, becoming its president in March 1960 and remaining so until his death. In 1941, he was elected member of the Royal Academy of Sciences and Arts of Belgium, and in 1953, he was given the inaugural Eddington Medal awarded by the Royal Astronomical Society. He died on 20 June 1966, shortly after having learned of the discovery of cosmic microwave background radiation, which provided further evidence for his intuitions about the birth of the Universe.
At yovisto, you can learn more about George Lemaître’s ideas about the origins of our universe in the talk of Prof. Stephen Hawking on ‘Asking Big Questions about our Universe‘.
References and Further Reading:
- The Big Bang Theory is introduced at A Science Oddisea
- Mark Midbon: ‘A Day Without Yesterday’: Georges Lemaitre and the Big Bang at Catholic Education Resource Center
- Blast of Giant Atom Created Our Universe at Modern Mechanics (1932)
Related Articles at Yovisto Blog:
- Fred Hoyle and the Big Bang Theory
- Sir Arthur Eddington – The Man who Proved Einstein’s General Relativity