In 1927, a Belgian priest and physicist named Georges Lemaître proposed a radical idea. Using Einstein's own equations, he suggested the universe was not static, but expanding.
Two years before Edwin Hubble's famous observations confirmed it, Lemaître had already laid the groundwork. When he personally presented his theory to Einstein, the famous physicist dismissed it, reportedly calling it “abominable.”
Undeterred, Lemaître refined his work. In 1931, he published a paper proposing that the universe began from an initial point, which he called the “primeval atom” or the “cosmic egg.”
This was the first formulation of what would later, mockingly, be called the “Big Bang” theory by its chief critic, Fred Hoyle.
After Hubble’s evidence of galactic redshifts became widely known, Einstein had a change of heart. He publicly praised Lemaître’s work as “the most beautiful and satisfactory explanation of creation” he had ever heard.
Still, the theory remained on the fringe for decades. It wasn't until the 1960s, with the accidental discovery of cosmic microwave background radiation, that Lemaître's “primeval atom” was finally vindicated as the leading model for the origin of the universe.
Lemaître, who served as a decorated artillery officer in WWI before entering the priesthood, always maintained that his faith and his science were two separate paths to truth.
*From Navin T. on LinkedIn
Lemaître studied engineering, mathematics, physics, and philosophy at the Catholic University of Louvain and was ordained as a priest of the Archdiocese of Mechelen in 1923. His ecclesiastical superior and mentor, Cardinal Désiré-Joseph Mercier, encouraged and supported his scientific work, allowing Lemaître to travel to England, where he worked with the astrophysicist Arthur Eddington at the University of Cambridge in 1923–1924, and to the United States, where he worked with Harlow Shapley at the Harvard College Observatory and at the Massachusetts Institute of Technology (MIT) in 1924–1925.
Lemaître was a professor of physics at Louvain from 1927 until his retirement in 1964. A pioneer in the use of computers in physics research, in the 1930s he showed, with Manuel Sandoval Vallarta of MIT, that cosmic rays are deflected by the Earth's magnetic field and must therefore carry electric charge. Lemaître also argued in favor of including a positive cosmological constant in the Einstein field equations, both for conceptual reasons and to help reconcile the age of the universe inferred from the Hubble–Lemaître law with the ages of the oldest stars and the abundances of radionuclides.
his paper, “Un univers homogène de masse constante et de rayon croissant, rendant compte de la vitesse radiale des nébuleuses extragalactiques” (“A homogeneous universe of constant mass and increasing radius, accounting for the radial velocity of extragalactic nebulae”), appeared in the Annales de la Société Scientifique de Bruxelles, vol. 47A.
In that paper (May 1927), Lemaître independently derived what we now call Hubble’s law, two years before Edwin Hubble’s 1929 publication — showing that galaxies’ recessional velocities increase with their distances, implying cosmic expansion.
That journal was a relatively obscure Belgian scientific periodical — which is one reason his revolutionary idea went largely unnoticed until the English translation appeared in 1931 in the Monthly Notices of the Royal Astronomical Society (MNRAS).
When Georges Lemaître’s 1927 paper was translated into English and published in the Monthly Notices of the Royal Astronomical Society (MNRAS, vol. 91, 1931, pp. 483–490), several key sections were omitted — not by the editors, but by Lemaître himself at the translator’s request.
Here’s what happened:
In his original 1927 French paper, Lemaître not only proposed an expanding universe model but also derived a numerical relationship between galaxy velocities and distances — essentially what we now call Hubble’s law — using available data from Vesto Slipher and others.
He even estimated a value for the expansion rate (what we now call the Hubble constant) of about 625 km/s/Mpc, very close to Hubble’s later 1929 estimate of 500 km/s/Mpc.
In the 1931 English version, the sections containing the numerical derivation and data table were deleted.
Lemaître explained later that he omitted them because, by 1931, Hubble’s 1929 observational paper had already provided more accurate data, and he considered his old numbers obsolete.
As a result, the 1931 publication emphasized the theoretical framework but not the empirical discovery, leading many readers to assume that Hubble, not Lemaître, had first found the linear velocity–distance relation.
It wasn’t until 2011, when historians revisited the correspondence and the original French paper, that the full extent of Lemaître’s priority became widely recognized — leading the International Astronomical Union in 2018 to officially recommend calling it the Hubble–Lemaître Law.
Robert Millikan, Lemaître and Albert Einstein after Lemaître's lecture at the California Institute of Technology in January 1933.
No comments:
Post a Comment