Allegations that astronomical pioneer Edwin Hubble may have actively censored the work of one of his competitors have taken on a new twist with the discovery of a letter casting light on the circumstances surrounding the alleged censorship.
Hubble is frequently credited with discovering that the universe is expanding, due to a groundbreaking 1929 paper in which he presents observational evidence for the correlation, now known as Hubble’s Law, between the distance of galaxies from Earth and their apparent velocity. Most historians credit Belgian astronomer Georges Lemaître with first formulating that relationship in an obscure 1927 paper published in French.
In recent months, amateur historians and astronomers have been buzzing over small but significant differences between Lemaître’s 1927 paper, and a 1931 translation that appeared in Monthly Notices of the Royal Astronomical Society. Then, on 20 June, David Block, a mathematician at the University of the Witwatersrand in Johannesburg, South Africa, and an amateur historian, alleged in a preprint that Hubble may have had a hand in the omission of part of Lemaitre’s work from the translation; specifically, paragraphs and part of an equation that included an empirical determination of the constant now known as the Hubble constant that governs Hubble’s Law. Professional historians were skeptical, demanding a paper trail to prove that the omissions were intentional and that Hubble was involved.
The identity of the translator was thought to be unknown. But now in an update to his original preprint Block says a letter has emerged from the Lemaître archives in Louvain, Belgium, suggesting that the translator was actually Lemaître. In a 1931 letter, Scottish astronomer William Marshall Smart, who handled the translation for the Monthly Notices of the Royal Astronomical Society, writes to Lemaître to ask him to translate his paper from paragraphs 1-72. That would carefully omit paragraph 73, the equation in which the determination of the constant that later became known as Hubble’s constant appears. While this doesn’t demonstrate that Hubble communicated with or influenced Smart, Block notes that Smart would have been aware of Hubble’s desire to be credited with determining the Hubble constant and his “complex personality.”
Historian Robert Smith of the University of Alberta in Edmonton, Canada, says to make sense of the Smart letter it’ll be necessary to study more correspondence from the time. “However, it’s very good that people are looking for further relevant material. It’s also important to have established that the translator was Lemaître himself,” he says. Smith adds that in his view, on a first read, Smart appears to have been acting more as an editor than a censor, asking Lemaître to omit bits of the paper that had been superceded since its original publication in French.
Image: Extract of the letter from Smart to Lemaître, Lemaître Archives, via David Block’s preprint.