Georges Lemaître (1894–1966) was a Belgian Catholic priest, astronomer, and physicist who first proposed the expanding universe and formulated the Big Bang theory, known as the 'primeval atom' hypothesis. His work laid the foundation for modern cosmology.
Georges Lemaître was born on July 17, 1894, in Charleroi, Belgium. He would become a pioneering physicist and priest who formulated the Big Bang theory. #history #cosmology
At the outbreak of World War I, Lemaître enlisted in the Belgian army and served as an artillery officer. He received the Croix de guerre for his bravery. #history #war
After WWI ended, Lemaître was demobilized and returned to civilian life. He resumed his studies in mathematics and physics. #history
Lemaître began his higher education at the Catholic University of Leuven, studying mathematics and physics. He earned a doctorate in mathematical sciences in 1920. #education #history
Lemaître obtained his PhD in mathematical sciences from the Catholic University of Leuven, with a thesis on approximations. He then entered the seminary. #education #history
After completing his doctorate, Lemaître decided to become a priest and entered the Seminary of the Archdiocese of Malines. He continued studying theology and astronomy. #religion #history
Lemaître was ordained a priest on September 22, 1923, in the Archdiocese of Mechelen. He balanced his scientific career with his religious duties. #religion #history
Lemaître received a fellowship from the Belgian government to study at the University of Cambridge under the astrophysicist Arthur Eddington. He worked with Eddington on cosmology. #education #cosmology
Lemaître moved to the US to study at the Massachusetts Institute of Technology and Harvard College Observatory. He worked with Harlow Shapley and others. #education #cosmology
While at Harvard, Lemaître attended a lecture by Harlow Shapley on the nature of spiral nebulae, which influenced his later work on the expansion of the universe. #cosmology #astronomy
In a seminal paper published in Annales de la Société Scientifique de Bruxelles, Lemaître derived Hubble's law from Einstein's equations, showing that the universe is expanding. This predates Hubble's later observational discovery. #cosmology #science
Lemaître was awarded a second PhD in physics from the Massachusetts Institute of Technology for his work on the gravitational field in a spherical fluid. #education #science
After completing his PhD at MIT, Lemaître returned to Belgium and became a part-time professor at the Catholic University of Leuven, later a full professor. #career #history
Edwin Hubble published observational evidence for the expansion of the universe, confirming Lemaître's earlier theoretical derivation. Lemaître's work was initially overlooked. #astronomy #cosmology
Arthur Eddington, impressed by Lemaître's 1927 paper, arranged for its translation into English and published it in the Monthly Notices of the Royal Astronomical Society, gaining wider recognition. #cosmology #science
Lemaître presented his primeval atom hypothesis at the British Association for the Advancement of Science meeting in London, sparking debate among scientists. #cosmology #science
Lemaître published a short paper in Nature proposing that the universe began as a single quantum, the 'primeval atom', which exploded to create space and time. This is the first formulation of the Big Bang theory. #bigbang #cosmology
Lemaître further developed his theory, describing the primeval atom as a 'cosmic egg' containing all matter, which underwent radioactive decay, leading to the universe's expansion. #cosmology #bigbang
During a visit to the California Institute of Technology, Lemaître met Albert Einstein, who initially rejected the concept of an expanding universe but later accepted Lemaître's theory after Shapley's support. #cosmology #history
After a lecture by Lemaître at Caltech, Einstein stood up and applauded, reportedly stating that his own cosmological constant was his 'greatest blunder'. This marked a turning point for the Big Bang idea. #cosmology #science
Lemaître was elected a member of the Pontifical Academy of Sciences, an institution he would later lead. He contributed to its scientific activities. #science #religion
Lemaître was elected a member of the Royal Academy of Belgium for Sciences and Arts, recognizing his work. #award #science
Lemaître published his major work 'L'Hypothèse de l'Atome Primitif' (The Hypothesis of the Primeval Atom), elaborating his Big Bang theory. The book was later translated into English. #bigbang #cosmology
During World War II, Lemaître remained in Belgium, teaching at Leuven and continuing his research despite the occupation. #history #war
Lemaître was appointed Director of the International Institute of Physics in Belgium, a position he held until 1966. #career #science
Lemaître wrote a popular science book 'The Primeval Atom' to explain his cosmological theories to a broader audience, spreading the Big Bang concept. #science #bigbang
The Royal Society of Belgium awarded Lemaître its Gold Medal for his contributions to astronomy and cosmology. #award #science
Lemaître was awarded the prestigious Francqui Prize in Exact Sciences, recognizing his revolutionary contributions to cosmology. #award #science
Lemaître was elected a Foreign Associate of the National Academy of Sciences of the United States. #award #science
The Royal Astronomical Society awarded Lemaître the Eddington Medal for his work on the expansion of the universe and the primeval atom. #award #cosmology
Lemaître was elected a Foreign Member of the Royal Society (ForMemRS), the UK's national academy of sciences, honoring his international standing. #award #science
The Société Française d'Astronomie awarded Lemaître the Jules Janssen Prize, the society's highest honor, for his astronomical achievements. #award #astronomy
Pope John XXIII appointed Lemaître as President of the Pontifical Academy of Sciences, a position he held until his death. He promoted scientific dialogue with the Church. #science #religion
Lemaître published his last scientific paper on the measurement of the Hubble constant, refining his earlier calculations. #cosmology #science
As President of the Pontifical Academy, Lemaître organized a 'Study Week on the Problem of the Galaxies' at the Vatican, bringing together leading astronomers. #science #cosmology
Lemaître was diagnosed with leukemia, but he continued his work and scientific activities despite his illness. #health #history
Penzias and Wilson announced their discovery of the cosmic microwave background radiation, which Lemaître recognized as strong evidence for his Big Bang theory, bringing him great satisfaction. #bigbang #cosmology
Georges Lemaître died on June 20, 1966, in Leuven, Belgium, at the age of 71. His pioneering work laid the foundation for modern Big Bang cosmology. #history #cosmology