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Humanity loves stories. I love stories. From the time of Homer in Greece of the seventh century BC, the first storyteller of the literate Western tradition; from the time of Gilgamesh, King of Uruk, from sometime between 2,800 and 2,500 BC—the epic poem about him was the first known work of literature—poets have been putting their thoughts into story form. Not just chants or prayers or tributes to gods and goddesses, but coherent tales of action and dialogue, of sequence and consequence, of cause and effect. This is what sets us apart from the chatter of monkeys, the mindless songs of whales, and the howling of wolves.
The Bible, Old Testament and New, is a series of stories. The creation of the world, where God—the one true god, the only god, the supreme being—divides the light from the darkness, the water from the land, the animals from the new creation, Man. That beginning is a story that starts from nothing but the mind of God and proceeds to build a world.
And that story as much as anything set the human mind—or at least its Western variant, the Judeo-Christian tradition—up to see the world as a created place. It didn’t just exist for all time, as far as anyone knew. It had a start, a point at which something came out of relative nothing. Other traditions have their creation stories. For example, in the American Northwest, the native cultures believe that Great Raven made the world, the mountains, and the tides.
I suppose that, absent the ingrained need to tell stories, any observant and inquisitive mind would ponder how the world came into being. Such a mind would note that the nature of mountains and hills is to break down—through erosion, landslides, rockfalls—but never to build up. Such a mind as Leonardo Da Vinci’s, as recounted by paleontologist Stephen J. Gould,1 noted that mountaintops sometimes contained the fossils of sea creatures, and he wondered about them. In fact, humanity didn’t have an adequate explanation for the rise of mountains until the theory of plate tectonics was first proposed in the early 20th century and validated by evidence of the seafloor’s spreading in the 1950s and ’60s. But without that theory, mountains can be observed to break down from known causes but must be imagined to rise due to … earthquakes, convulsions, or the Hand of God.
Back when the Bible writers and Renaissance polymaths were wondering about such things, the world was just this one planet. The Earth was the central place of the universe, while everything else—Sun, Moon, other planets, and the stars in the night sky—was just a set of ornaments provided to heat this world, keep track of the months (and cause madness), and aid human beings with navigation. Otherwise, Earth was the place that mattered.
It wasn’t until that same early 20th century that humanity knew there were stars beyond the stars we could see. The “galaxy” was the Milky Way, the concentration of stars like a river in the night sky. But some of those “stars” were distinct points of light, while others were fuzzy patches that astronomers called “nebulae,” or clouds. With better telescopes, they could decide that some of these cloudy objects appeared to be actual backlit clouds of dust and gas, the remnants of exploded stars. But others remained just fuzzy patches. It wasn’t until Edwin Hubble announced in 1924 that the patch everyone called “Andromeda”—after the mythological daughter of Aethiopian King Cepheus and his wife Cassiopeia—was actually another galaxy, like our own Milky Way, but far off.
Just as Nicolaus Copernicus, with his new model for the motions of the Sun and Earth, turned “the world” into a solar system with other planets no less important than our own, so in one step Hubble expanded “the universe” from an island of local stars into a vastness of galaxies, hundreds of them, perhaps thousands, no less important than the stars we can see around us. It would take much larger telescopes, including the orbiting scope named after Hubble himself, to see that there are actually billions, if not a couple of trillion, galaxies expanding in clusters and webs that extend into the space beyond which even our most powerful telescopes can see.
Hubble also noted that the light from these distant objects was “redshifted,” or appeared farther down the spectrum and at lower energy levels than the light from stars in our own galaxy. This suggested to him and to other astronomers that those other galaxies were expanding away from us, and so the universe itself must be expanding.
By modeling the life cycle of stars based on size and temperature, calculating the age of the oldest stars according to this cycle, and figuring out how stars create the various elements by fusion—from helium out of hydrogen; then the lighter elements and metals through iron; and finally the heaviest extant elements like gold, lead, and uranium from the collapsing pressure of supernovas—astrophysicists could determine the various generations of stars needed to make up the universe we can observe. They came up with a probable age for the universe of about 13 billion years.
If the universe is expanding, it is reasonable to assume that it has always been doing so. And then, if you “roll back” that observed expansion by 13 billion years, you come to a point in primordial space. All the stars we can see, and the dust and gas we can’t directly see, everything in the universe collapses down to a point that’s infinitely small. And because it’s so packed with material, that point or singularity must be infinitely hot and dense and just waiting to explode. That’s what must have happened: this infinitely tiny, infinitely dense, infinitely hot thing exploded and spewed out all the matter in the universe. And this hot stuff then began expanding and cooling and evolving into protons, electrons, neutrons, neutrinos, and all the other subatomic particles, and finally into coherent matter in the form of hydrogen atoms. At the same time, residual energy in the form of fast-moving photons made light waves and all the variable energies we can detect. And after a time of expansion, bits of the local scene began to contract under gravity—as stars still do today—until they could ignite a fusion reaction and begin making the other elements out of those hydrogen atoms.
All of this was called the “Big Bang” theory, somewhat derisively, by astronomers who instead assumed that the universe had always existed in a “Steady State.” The two sides might never have resolved their positions, until in 1965 two engineers at Bell Labs in New Jersey, Arno Penzias and Robert Wilson, discovered the Big Bang’s echo. They were trying to fix the radio interference that was plaguing a giant radio antenna that was supposed to pick up satellite communications. Nothing they tried—even sweeping it for physical debris such as twigs and leaves—could clear up the signal. It was a low hum, energy at an almost stone-cold 2.3 degrees Kelvin, or -455.53 degrees Fahrenheit. This temperature matched theories that predicted those high-energy photos released in the Big Bang would, over a time of 13 billion years, have cooled to a microwave background radiation at just such a frequency.
That was proof of the Big Bang as the creation story of the universe. There was just one problem: if you rolled the apparent size of the observable universe back to that single point, it takes a lot longer than 13 billion years for it to expand. In other words, even if the universe expanded outward from that point at the speed of light, it would be a smaller universe than the one we can see today. This puzzled astronomers until a professor at Cornell, Alan Guth, in 1979 conceived of Inflation Theory. This theory said that in the period between 10-36 seconds and perhaps 10-33 or 10-32 seconds after the singularity exploded, and for reasons that are not explained, the space containing that outpouring of material expanded exponentially at much greater than light speed. It went from a zero-dimension point to about 0.88 millimeter—about the size of a grain of sand—in virtually no time, and afterwards the universe expanded at a much slower rate. This inflation period accounts not only for the current size of the universe but also its apparent smoothness.
And all of this story—from the discovery of other galaxies and the expansion of the universe, to the Big Bang, to the inflation that explains the Big Bang—has been conceived from observations and worked out with intense mathematical calculation within the last hundred years. Much of that calculation—if laymen can follow the numbers at all—grapples with issues of general relativity.
According to general relativity, time and space, or timespace, have/has no fixed or absolute value. Instead, they are true and fixed only for the local observer and based on his or her speed and the gravity well in which the observer finds him- or herself. People traveling faster or existing under heavier gravity experience the passage of time at a slower rate and the shape of space at a greater curvature than people living in slower, more open domains.
But also, according to general relativity, the speed limit of the universe is fixed at the speed of light, c, or 186,272 miles (299,792 kilometers) per second. So regardless of how compact the Big Bang mass might have been, its speed of expansion according to any observation was pegged at that amount of distance over time … or not.
Doesn’t this all seem to be just a bit too artificial? Massive singularities, rapid expansion, a fixed age for a universe that is continually expanding, with temporary conditions that violate other theories. As I have stated elsewhere,2 we may not yet understand the nature of space, time, and gravity at all. So we may not be equipped to unravel the nature of an expanding universe or roll its scale back to the infinitesimal spitball of hot matter that the Big Bang requires.
We may instead be living in an age of conjecture comparable—but with more sophisticated theories and advanced mathematics—to the years between Copernicus’s modeling of the sun-centered universe in 1543 and Kepler’s working out the theory of planetary motion as ellipses rather than perfect circles in 1619. And now we are waiting for a better theory of space, time, and gravity to account for our developing observations.
But then, on the other hand, why did the universe need to be created at all?
1. See Leonardo’s Mountain of Clams and the Diet of Worms: Essays on Natural History, from 1998.
2. See Fun with Numbers (I) from September 19, 2010, and (II) from September 26, 2010.