Pre-Twentieth Century Ideas of Universe’s Origins




 

The origins of creation have, of course, preoccupied humanity since at least the beginning of civilization itself. Virtually every culture around the world has created myths to explain how the universe came into being, even if they did not necessarily comprehend the universe’s magnitude and complexity. These cosmologies, or explanations for the existence of creation, generally share four basic ideas. First, there is an intelligence or creator behind creation. Second, the universe came into being at a specific point in time and that what existed before the universe came into being is irrelevant as there was no existence or time before it. A major exception to this model of a universe created at a single moment in time comes from Hindu cosmology which states that the universe exists in cycles, of roughly 4.5 billion years, or one day in the life of the Brahma, the creator, endlessly being born, dying, and being reborn. The third component of most ancient cosmologies was that the Earth stood at the center of creation.

And the final element was that, once the universe was created, it remained essentially static--nothing added, nothing taken away, all matter and energy in perpetual balance. That, too, was the model advanced by English scientist Isaac Newton in the late seventeenth and early eighteenth centuries, whose understanding of the laws of the universe dominated physics for more than 200 years. But even in Newton’s own time, the idea of a perpetually balanced creation was questioned by some thinkers, who pointed out that the universe would come apart if just one object should slip out of balance. And while Newton’s laws attempted to explain how the universe operated, they did not offer much insight into its origins.

Immanuel Kant, a German philosopher of the late eighteenth century, was the first major Western thinker to tackle the question that the Big Bang theory would eventually answer—had the universe always existed or did it come into existence at a specific point in time? Kant concluded that since both arguments were equally valid on the face of things and that it was impossible to determine which was fundamentally true, the question of the universe’s origins, or lack thereof, was beyond human comprehension. Even as nineteenth century astronomers began to push back the envelope of what was known about the universe’s scale, they did not have the means or, given their religious faith, the inclination to grapple with Kant’s question.


Early Hypotheses

 

Early twentieth century physicists and astronomers, of course, would prove Kant wrong. In 1912, an American astronomer named Vesto Slipher noted a Doppler shift in the wavelengths of light coming from spiral nebulae, an antiquated term for galaxies, dating from before the existence of other galaxies was confirmed. (It was American astronomer Edwin Hubble who first concluded in the mid-1920s that the nebulae were, in fact, galaxies similar to our own Milky Way.) The Doppler shift, named after Christian Doppler, the early nineteenth century Austrian mathematician who discovered it, says that waves alter in relation to the movement of the observer or the object causing the wave. While Slipher noted that almost all such spiral nebulae were moving away from the Earth, he failed to reach the conclusion that this meant the universe was expanding.

Around the same time, Slipher was making his observations, Friedmann, the Soviet physicist, explained how Einstein’s General Relativity Theory might prove that the universe was expanding. Einstein’s theory updated and revised Newton’s gravitational laws, for conditions where enormous mass and energy existed. Newton concluded that gravity was a force between two masses; Einstein argued, correctly as it was proved by later experiments, that gravity was the warping of space and time caused by mass. While Newton’s model of gravity was not consistent with the Big Bang theory—since there was no mass in the primordial state of heat and density at the beginning of time—Einstein’s allowed for the possibility of gravity itself coming into being, though, ironically, Einstein himself held to a static view of the universe when he came up with his General Relativity Theory.

Roughly a decade after Friedmann developed his models out of Einstein’s General Relativity Theory—models that, while published, generally got overlooked by other physicists--a Belgian physicist and astronomer Georges Lemaître, independently coming up with the same theories as Friedmann, used them to reach the conclusion that had eluded Slipher—that receding nebulae meant the universe was expanding. In 1931, Lemaître also hypothesized that the universe must have begun with a single atom, an idea that came to be called the “cosmic egg” theory. American astronomer Edwin Hubble, the first to realize that nebulae were in fact other galaxies, also confirmed that the galaxies all seemed to be moving away from us simultaneously. Extrapolating backward, Hubble believed that they all had emerged from the same high-density place, exploding outward in a kind of initial fireball. Hubble made his findings by noting shifts in the light spectrum of distant galaxies that fit in with the Doppler effect.

Despite such findings, a competing theory emerged in the years after World War II,. The “steady state” model, advocated by British astronomer Frederick Hoyle, held that new matter was created as the universe expanded. A confirmed atheist, Hoyle rejected the “cosmic egg” theory as it seemed to imply the existence of a creator. Ironically, it was Hoyle who, in the 1950s, coined the term “Big Bang,” using it in a radio interview to ridicule Lemaître’s ideas. To reconcile his constant universe idea and the observed fact that galaxies were moving away from each other, Hoyle hypothesized that new galaxies came into being as older ones grew apart. While later discounted, Hoyle’s work was useful in explaining how matter and energy came into existence, a key component of the Big Bang theory.

 



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