By Bill Schmitt

The Society of Catholic Scientists hails the vote of the membership of the International Astronomical Union to recommend renaming the famous Hubble Law of cosmology as the Hubble-Lemaître Law to honor Fr. Georges Lemaître (1894-1966), the Catholic priest and theoretical physicist who proposed the Big Bang theory in the late 1920’s. 

The Hubble-Lemaître Law states that distant objects in an expanding universe move apart at a rate proportional to their distance from each other.  The American astronomer Edwin Hubble discovered this law from observations in 1929. Hubble and most other scientists at the time were unaware that Lemaître had predicted the law from his theory of an expanding universe two years earlier. 

Partly because of his self-effacing ways and lack of interest in getting credit for his ideas, Lemaître tended to be overshadowed by other cosmologists, but the magnitude of his contributions is being increasingly acknowledged.  For example, it is becoming more common to refer to the solution of Einstein’s equations that describes an expanding homogenous universe as the “Friedmann-Lemaître-Robertson-Walker (or FLRW) metric.” (Friedmann and Lemaître were the first to write the solution down, independently of each other.)  

The vote of the membership of the IAU to rename the Hubble Law in honor of both Hubble and Lemaître was overwhelming, with 78% of votes in favor.  

Prof. Jonathan Lunine will be giving a public lecture about Fr. Lemaître on Oct. 31 at the University of Chicago.

For those interested in learning more about Lemaître and his work, two talks about him given by members of the SCS Board can be viewed in the Video Archive of the SCS website:

1… “Lemaitre, Modern Cosmology and the Compatibility of Science and Faith,” given by Prof. Jonathan Lunine of Cornell University (SCS Vice President) in November 2018 at University of Notre Dame. (See under “Recommended” in the Video Archive.)

2… “Georges Lemaître’s Contributions to Cosmology,” given by Prof. Robert Scherrer of Vanderbilt University (SCS Secretary) in April 2017 at the first SCS conference.  (See under “2017 Conference: Origins” in the Video Archive.)

Videos about several other great scientists who were Catholic priests (Mersenne, Secchi, Mendel, Steno) can also be found in the SCS Video Archive.