Cosmic Seer

Georges Lemaître, the Catholic Priest Behind the Big Bang

Pope Francis made news a while back when he said that the Big Bang theory does not contradict the religious idea of creation. This comment was seen as interesting because the Big Bang theory has often been intertwined with the secular notion of how our universe came to be. Because of this longstanding secular connection, many would be surprised to learn that the first person to advance the concepts behind the Big Bang theory was not only a physics professor but also a Belgian Catholic priest by the name of Georges Lemaître.

It has been suggested that Lemaître, as a young man in the military, chose the priesthood after witnessing the horrors of World War I and the murderous abomination of poison gas. This was not the case, though. In fact, Lemaître had decided on his dual vocation as priest and scientist before he was ten years old. This precocious decision likely encountered no resistance from his ardently Catholic family. And neither as a child nor as an adult would he see a conflict between his priestly and scientific ambitions.

Lemaître was born on July 14, 1894, in Charleroi, Belgium, the eldest son of a father who worked as both a glassblower and a lawyer. Georges showed early signs of brilliance at the Jesuit school in his hometown, and, after six years there, he headed to the College Saint Michel, a Jesuit prep school in Brussels. He then enrolled at the Catholic University of Leuven, where he majored in civil engineering. It was not his first choice, but engineering seemed a more practical way to assist his siblings financially, according to The Day Without Yesterday, a biography of Lemaître by John Farrell.

The would-be engineer's education was interrupted by the outbreak of World War I. Lemaître served in the Belgian army as an artillery officer for four years, during which time he impressed his comrades by devouring physics textbooks in the interludes between military engagements on the battlefront. When he returned to school after the war, he changed his focus from engineering to physics. He also entered a seminary in 1920 and was ordained a priest in 1923. During this time, he became increasingly preoccupied with the cosmology of Albert Einstein.

The Theory of an Expanding Universe

After his ordination, Lemaître won a scholarship to study abroad and headed to Cambridge University, where he worked with the astronomer Arthur Eddington. He then migrated from Cambridge in the U.K. to Cambridge, Massachusetts, so he could study at Harvard and M.I.T., where he earned a doctoral degree. Returning to Belgium (at least for a while), he was appointed professor of physics at the Catholic University of Leuven. Right around this time, he published the formidably titled paper, "A Homogenous Universe of Constant Mass and Increasing Radiation, Taking Account of the Radial Velocity of Extragalactic Nebulae," which questioned Einstein's idea of a static universe.

Unknown to Lemaître, there was a Russian mathematician, Alexander Friedmann, who had authored a series of equations in 1922 that supported the concept of an expanding universe. Friedmann had actually sent a letter, including his equations, to Einstein. But the man whose last name is now synonymous with brilliance carelessly dismissed the letter, along with its astrophysical implications. Friedmann, as a mathematician, was interested in the expanding universe idea purely in the abstract, and he never really pursued it further—though in fairness to him, he did not have much opportunity, as he was fatally stricken by typhoid fever in 1925.

By the latter half of the 1920s, Lemaître had taken the concept further than Friedmann or anyone else. His contention was that, if the universe is expanding, then it must have been smaller in the past—increasingly so the farther back in time it went, all the way back to a point when everything was packed together into a spectacularly dense particle—labeled a "primeval atom"—which, by exploding, created time, space, and this ever-expanding universe.

Lemaître presented this theory in writing to Einstein in October 1927, when the two first met at a conference in Brussels. As the priest later recalled, Einstein's response was, "Your calculations are correct, but your physics is abominable." Lemaître's work was more or less dismissed by the New York Times, which called his theory "highly romantic." The encyclopedia Notable Scientists said that Lemaître's main problem was that his theory "lacked sufficient mathematical backing for widespread acceptance." Such backing would arrive in the fullness of time.

As his esteem grew, Lemaître received his share of media attention, much of which ignored his actual contributions and tended to marvel at the fact that he was both a priest and a physicist. Though he took this in stride, he was irritated when Pope Pius XII pointed to his theory as scientific evidence for a God-created universe. Lemaître feared that his scientific colleagues would criticize his theory as being inspired by faith rather than science.

Soon enough, though, his theory was validated to the point where it was generally accepted by almost everyone in the scientific community. Other astrophysicists built on his work to form the modern version of the theory of the Big Bang—a term coined in 1950 by the British astronomer Fred Hoyle.

The Power Behind the Stars

In 1960, Lemaître was appointed president of the Pontifical Academy of Sciences. Despite his emphatic separation of science and theology, he could not help but notice that there were a good number of believers among scientists, particularly among those involved with astronomy and physics. Of such scientists, he said, "The deeper they penetrated into the mystery of the universe, the deeper was their conviction that the power behind the stars and behind the electrons of atoms was one of law and goodness."

Who or what else but God himself could transform a single atom into a universe spanning many billions of light years? With the emergence of the Big Bang theory, atheism began to require more "belief" than believing in God did. One atheist scientist even complained that his colleagues were joining the "First Church of Christ of the Big Bang." Evidently, these converts were beginning to see an ultimate progenitor who, generating matter from non-matter, lurked behind the creation of all objects and beings.

While visiting Rome in December 1964, Lemaître suffered a heart attack. He recovered his health somewhat, only to then find himself stricken by leukemia. He died in Belgium on June 20, 1966, at age 71. By then, he was known as the "Father of the Big Bang"—a theory that has since been embraced by atheists and believers alike. Though Lemaître kept his scientific and religious vocations separate, he followed them both as paths to ultimate truth. •