Put quantum mechanics and general relativity together and what do you have? Why, the theory of everything, of course, or more specifically, an explanation of how everything could have come from nothing at all. Something missing, you say? It's not quite holding together? Oh, OK, then there's the inherent instability of "nothing" and the fact (or what we now believe to be fact) that the universe is flat. For all this to work, it has to be, and so it is. Oh, and eternal inflation. There's that, too (http://www.bbc.com/earth/story/20141106-why-does-anything-exist-at-all).
The subtitle to the book from which this excerpt is drawn is Why There Is Something Rather Than Nothing.
(You can understand why I didn't try to squeeze it into the post title!) Usually, when introducing a book, I begin at the beginning (as the King told Alice to do). In this case, however, I will begin a couple of pages in, as the author, Lawrence M. Krauss, starts with Einstein's story, with which we're at least vaguely familiar, and I think we (or at least I) know a little less about this other major figure in the theory's history.
CHAPTER 1
A Cosmic Mystery Story:
Beginnings
The Initial Mystery that attends any journey is: how did
the traveler reach his starting point in the first place?
—LOUISE BOGAN, Journey Around My Room
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The discovery that the universe is not static, but rather expanding, has profound philosophical and religious significance, because it suggested that our universe had a beginning. A beginning implies creation, and creation stirs emotions. While it took several decades following the discovery in 1929 of our expanding universe for the notion of a Big Bang to achieve independent empirical confirmation, Pope Pius XII heralded it in 1951 as evidence for Genesis. As he put it:
It would seem that present-day science, with one sweep back across the centuries, has succeeded in bearing witness to the august instant of the primordial Fiat Lux [Let there be Light], when along with matter, there burst forth from nothing a sea of light and radiation, and the elements split and churned and formed into millions of galaxies. Thus, with that concreteness which is characteristic of physical proofs, [science] has confirmed the contingency of the universe and also the well-founded deduction as to the epoch when the world came forth from the hands of the Creator. Hence, creation took place. We say: "Therefore, there is a Creator. Therefore, God exists!"
The full story is actually a little more interesting. In fact, the first person to propose a Big Bang was a Belgian priest and physicist named Georges Lemaître. Lemaître was a remarkable combination of proficiencies. He started his studies as an engineer, was a decorated artilleryman in World War I, and then switched to mathematics while studying for the priesthood in the early 1920s. He then moved on to cosmology, studying first with the famous British astrophysicist Sir Arthur Stanley Eddington before moving on to Harvard and eventually receiving a second doctorate, in physics from MIT.
In 1927, before receiving his second doctorate, Lemaître had actually solved Einstein's equations for general relativity and demonstrated that the theory predicts a nonstatic universe and in fact suggests that the universe we live in is expanding. The notion seemed so outrageous that Einstein himself colorfully objected with the statement "Your math is correct, but your physics is abominable."
Nevertheless, Lemaître powered onward, and in 1930 he further proposed that our expanding universe actually began as an infinitesimal point, which he called the "Primeval Atom" and that this beginning represented, in an allusion to Genesis perhaps, a "Day with No Yesterday."
Thus, the Big Bang, which Pope Pius so heralded, had first been proposed by a priest. One might have thought that Lemaître would have been thrilled with this papal validation, but he had already dispensed in his own mind with the notion that this scientific theory had theological consequences and had ultimately removed a paragraph in the draft of his 1931 paper on the Big Bang remarking on this issue.
Lemaître in fact later voiced his objection to the pope's 1951 claimed proof of Genesis via the Big Bang (not least because he realized that if his theory was later proved incorrect, then the Roman Catholic claims for Genesis might be contested." By this time, he had been elected to the Vatican's Pontifical Academy, later becoming its president. As he put it, "As far as I can see, such a theory remains entirely outside of any metaphysical or religious question." The pope never again brought up the topic in public.
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