Georges Lemaitre

Belgian astrophysicist Georges Henri Édouard Lemaître proposed the Big Bang theory of the origin of the universe in 1927. This scientific theory describes the origin of all space, time, matter, and energy, 13.7 billion years ago, from the violent expansion of a singular point of extremely high density and temperature.

This associate of royal astronomical society and Jesuit-trained Catholic priest, mathematician, and astronomer, served as professor of physics at the Catholic University of Louvain. He first identified that a theory of an expanding universe, which Edwin Hubble observationally confirmed quickly afterwards, can explain the recession of nearby galaxies. He first derived the now known Hubble-Lemaître law and made the first estimation, now called the Hubble constant, which he published in 1927, two years before article of Hubble. Lemaître initially callied his theory the "hypothesis of the primeval atom."

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