Introduction
Georges Lemaître (1894-1966) was a Belgian cosmologist, Catholic priest, and father of the Big Bang theory. Lemaitre was a theoretical Physicist who studied at Cambridge University and was also a priest, and this is not completely uncommon in Science, as is perhaps well known. Gregor Mendel (the father of modern Genetics) was also a priest; Mendel, by the way, did his famous experiments on the breeding of different varieties of peas, leading to his laws.
Universe’s Expansion
Georges’ remarkable discovery using Einstein’s equations of General Relativity demonstrated that the universe is expanding and that this expansion could be calculated, in so doing, Lemaître was the first person to calculate a value for what today we call Hubble’s (1889-1953) constant. The incorrect naming of the Hubble constant is one of many misnomers in Science (and Mathematics) that we will have to save for a later day. Einstein(1879-1955) was very interested in Lemaître’s work and he (Einstein) is reported to have said to him: “Vos calculs sont corrects, mais votre physique est abominable” (“Your calculations are correct, but your physics is atrocious”).
One may recall that Einstein included what we call today Einstein’s cosmological constant in his equations (and which he called his “greatest blunder”) in an attempt to give rise to a static universe. In fact we think today that it is this constant that will elucidate “dark matter and energy” arising from Quantum Mechanical considerations.
Overthrowing Giant’s Theories
Returning to Lemaître, he was taught by Einstein’s great Champion, the Astronomer Royal, Arthur Eddington (1822-1944). Eddington was also Senior Wrangler (an award he won whilst a second-year undergraduate) who introduced General Relativity to Lemaître. Remaining for a moment with Arthur, it was he during an evening in May 1919 whilst watching the solar eclipse in Principe and calculating the bending of light due to a massive object (in this case, our sun) that numerical results were provided that were used to test the accuracy of Newton’s (1643-1727) and Einstein’s theories of gravity, and as is well known it was Einstein’s theory that was found to agree better with experiment. Thus the toppling of the Newtonian worldview was complete. Arthur is also the proud owner of one of the most accurate (and amazingly profound) quotes in all of Science:
“The law that entropy always increases holds, I think, the supreme position among the laws of Nature. If someone points out that your pet theory of the universe disagrees with Maxwell’s equations – then so much the worse for Maxwell’s equations if it is found to be contradicted by observation – well, these experimentalists do bungle things sometimes. But if your theory is against the Second Law of Thermodynamics, I can give you no hope; there is nothing for it to collapse in deepest humiliation.” A. Eddington.
Good Bye!!
Unfortunately, I must admit that I have meandered off-piste and have no room left to discuss Lemaître, despite my best intentions. So my apologies “old friend”.
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