The Day We Found the Universe - Marcia Bartusiak [130]
From our perspective, it appears that all the galaxies in the universe are rushing away from us—that we are somehow situated at the very center of the cosmic action—but in reality you would observe the same dash outward from any other galaxy in the universe. Lemaître was the first to say directly that the galaxies are fleeing from us because space-time at each and every point throughout the cosmos is continually stretching. The galaxies are not rushing through space but instead are being carried along as space-time inflates without end. The embedded galaxies are simply going along for the ride. That's why the recession occurs in a specific way: A galaxy twice as far from us recedes twice as fast; a galaxy three times farther travels three times faster, and so on. Lemaître even estimated a rate of cosmic expansion (625 kilometers per second per megaparsec, based on the galactic velocity and distance data then available) that was close to the figure of 500 that Hubble would later calculate.
This was a tremendous accomplishment and offered an astounding vision of how the universe operates. But no one noticed—no one at all. Lemaître's paper, like Friedmann's earlier, was completely ignored. It was as if the article had never been published. Lemaître traveled in Europe and the United States afterward but inexplicably did not widely discuss this latest idea with his colleagues, either in person or in letters. Throughout his deliberations, he had been in contact with astronomers who would have been tremendously interested in his new take on the universe, such as Shapley, Slipher, and Hubble. Yet he apparently kept silent. Either he still had doubts about his new cosmic model or his ardor was dampened by encounters he had with the architects of the leading cosmological models. Though outwardly an extrovert, Lemaître was still quite sensitive to the smallest slight. In October 1927, just six months after his paper came out in the Belgian journal, he met with Einstein during the Fifth Solvay Congress in Brussels, a triennial meeting of the world's top physicists, and the two had a brief chat about Lemaître's breakthrough in the city's Leopold Park. It was at this time that Lemaître first heard from Einstein about Friedmann's similar solution. By then Einstein no longer had any objection to the mathematics in either man's model (his initial rejection of Friedmann's work had been based on an error in his own calculations), but he was still repelled by the image of the cosmos that the models of both Friedmann and Lemaître conveyed. “Your calculations are correct, but your physical insight is abominable,” asserted Einstein, who could not (and would not) imagine a universe in motion. Later, while accompanying Einstein on a university lab tour, the Belgian cleric continued to press his case, talking about the latest evidence on the galaxies' speeding away from Earth. But in the end he came away from the meeting with the impression that Einstein was “not current with the astronomical facts.” Nine months later at the 1928 General Assembly of the International Astronomical Union, de Sitter was equally dismissive of the little-known priest. As one commentator noted, de Sitter seemingly had “no time for an unassuming theorist without proper international credentials.”
Georges Lemaître with Albert Einstein in 1933 at the
California Institute of Technology (Courtesy of the Archives,
California Institute of Technology)
The impasse held until Hubble and Humason verified that