In 1929, Edwin Hubble published a paper showing that the universe is expanding*.  His empirical observation that distant galaxies were receding from us at a speed that is proportional to their distance away is now known as “Hubble’s Law.”  We have a space telescope named for him.  He was the first and deserves the credit, right?

Lemaître also showed that the universe is expanding and that the entire cosmos originated from a singularity (the “Big Bang Theory”) which he called, poetically, the “hypothesis of the primeval atom” or the “cosmic egg.” Interestingly, Einstein did not like the idea of an ever-expanding universe.  He certainly understood Lemaître’s solutions to his equations of General Relativity, but he famously remarked about this discovery that “Your calculations are correct, but your physics is atrocious.”  Lemaître earned his Ph.D. from MIT.  Lemaître was ordained a parochial priest, that is, not as a member of a Roman Catholic order such as the Jesuits or Benedictines.  He was the only theoretical cosmologist to be nominated for the Nobel Prize. Why was his work not given due credit as the first to hypothesize the Big Bang and the expanding universe?  Because he resided in Europe and published his papers in French in an obscure Belgian scientific journal.  The International Astronomical Union (the professional body of astronomers and cosmologists) recently debated renaming the Hubble space telescope and changing the name of the theory and its constant to the “Hubble- Lemaître constant.”  The proposal was voted down. During his tenure at the Catholic University of Leuven, Lemaître served as a professor of physics and celebrated mass at the university chapel on rotation with other priests.  I would have loved to hear him preach.