Previous posts in this chapter:
3.1 General and Special Relativity3.2 Three Cosmologies
3.4 Ex Nihilo Creation
3.5 The Cosmological Argument
3.6 The Fine Tuning Argument
3.7 The State of the Question
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3.3 In 1981, Alan Guth published a landmark paper hypothesizing that several problems in cosmology might be explained if the early universe underwent a rapid inflation in fractions of a second from a tiny, hot, dense state into a much larger size, from the microscopic to the macroscopic. [1] For one, there was the "horizon problem." This was the fact that the universe appears somewhat uniform in all directions even though it is not old enough for its parts otherwise to have ever been in contact with each other. Similarly, the universe is generally "flat," a condition that would not likely have been the case without some special circumstance such as the expansion Guth proposed.
Finally, "grand unified theories" had proposed that the fundamental forces of nature were all related to each other in the early universe. However, such theories imply the existence of monopoles, lone charges that might exist without their opposing charge. This phenomenon has never been observed. Guth proposed that they might have been so widely distributed by a rapid expansion of the early universe as to be undetected.
In the decades that have followed, a general consensus has emerged in terms of the timeline and sequence of the universe's early expansion. Later in the chapter, we will explore how the events that unfolded seemed to be "just right" for the universe to form in a way that would eventually allow for stars and planets such as ours. If we did not live in a "Goldilocks universe," none of us would be here today.
As in the image above, the universe is currently thought to have begun in an incredibly hot, dense singularity. Then, something pulls the trigger. It begins to expand rapidly. Three minutes later, we will have atomic nuclei. [2]
The Planck Epoch
In the time from beginning to nuclei, the universe will undergo several rapid "epochs." It starts in the Planck epoch. This is the time immediately after the Big Bang when the laws of physics as we now know them break down. The universe is arguably the smallest possible space, 10-35 meters, a quantum of space, and the smallest quantum of time passes, around 10-43 seconds. This is the starting line.
The Grand Unification Epoch
Then gravity distinguishes itself from the other fundamental forces. This is the "Grand Unification Epoch." In the next fraction of a second, from 10-43 to 10-36 seconds, the other fundamental forces are still combined. Only gravity has become an independent force.
The Inflationary Epoch
Now comes the inflation. In the period from 10-36 to 10-32 seconds, the universe goes from a subatomic size of 10-26 meters to about the size of a marble of 1cm. This is the period that Guth predicted, explaining the horizon problem, the flatness of the universe, and the lack of detecting monopoles.
The Electroweak Epoch
From 10-32 to 10-12 seconds, the strong nuclear force -- which eventually will hold the nuclei of atoms together -- distinguishes itself from the still combined other forces, called the "electroweak" force. The sphere of space that will become the universe is about 300 light seconds in size or a little more than half the distance from the Earth to the Sun.
The Quark Epoch
This epoch begins with the electroweak force dividing into the electromagnetic force and the weak nuclear force. We now have all four of the fundamental forces of nature. In this period from 10-12 to 10-6 seconds, we also see quarks and gluons dominate. In the Standard Model of Particle physics, quarks are some of the most fundamental of particles, thought to be the component parts of protons, neutrons, and a host of other subatomic particles. In this period, they are too hot to glue together yet, but make up a quark-gluon plasma. By the end of the epoch, the universe is about the size of our solar system.
The Hadron Epoch
Early in this period from 10-6 to one second, matter and antimatter annihilate each other following Einstein's famous equation, E = mc2. There is slightly more matter than antimatter, allowing the universe as we know it to continue to unfold. Quarks begin to fuse together to form some of the particles we learned about in high school -- protons and neutrons. The universe is now a second old, and it is now several light years across. A light year is the distance light travels in a year, going at a speed of 300,000 kilometers per second.
The Lepton Epoch
The next epoch begins as the universe cools enough for neutrinos to be liberated from matter. From about one to 10 seconds, the universe will expand to be a few million kilometers across. Particles like electrons and neutrinos dominate.
The Nucleosynthesis Epoch
From 10 seconds to about 3 minutes, the universe has cooled enough for protons and neutrons to fuse together to form nuclei. It is still too hot for electrons to orbit, but the nuclei of hydrogen, helium, as well as some deuterium and lithium to form. [4] The universe is now several light minutes across.
The Photon Epoch
Up to this point, it seems like there is little that might conflict between science and faith. In the standard timeline, the universe is only 3 minutes old. However, the current model now supposes a period of some 380,000 years in which the universe exists in a plasma of photons (light particles), electrons, and nuclei. The soup is initially too hot to form atoms, but it is cooling. By the end of this period, the universe is thought to be about 84 millions light years in diameter.
From about 280,000 years on, the universe is getting cool enough for atoms to begin to "recombine." This will gradually happen all over the universe, reaching the peak of recombination at the end of this epoch.
At the end of ths period, the universe cools enough for photons to be released. This is thought to be the basis for the cosmic microwave background that was discovered in 1965 by Penzias and Wilson. If one is sympathetic to the idea that the days of Genesis 1 could have been epochs, then it is fascinating that the event of Day 1 is the creation of light (Gen. 1:3). According to the current inflationary model, in the 380,000th year, the universe said, "Let there be light."
The Dark Ages
The universe grows dark. The frequency of the light from the cosmic photon release gets stretched as the universe expands and red-shifts everywhere. It goes into the infrared part of the spectrum, the stuff of night goggles. According to the prevailing model, the next 150 million years are a time when gravity slowly pulls hydrogen and helium together into clumps. The expansion was uneven, so there are concentrations of matter where galaxies can form. The dark ages end as the first stars ignite, and there is a cosmic dawn.
If you would like to take Genesis metaphorically, you might see this slow separation and gathering of hydrogen across the universe as analogous to the separation of the waters in Genesis 1:6-8. Now the sky appears.
Galaxy Formation
In the prevailing model, the next 300 million years or so see the formation of huge stars that burn out quickly. The first galaxies begin to form. In the current theory, the oldest observable galaxy is MoM-z14, thought to date to about 300 million years after the Big Bang.
Reionization Period
In the current model, at the same time galaxies are forming until about a billion years after the Big Bang, the newly formed stars and quasars begin to detach hydrogen nuclei from their electrons. It is called re-ionization because you'll remember that they had been separated in the early universe. Bubbles of ionized hydrogen gas merged with each other, leaving the transparent universe we see today when we look up to the skies.
Generations of Stars
For the next 8 billion years or so -- at least in the current model -- the first generation of stars burn out and go supernova. Some become black holes. Others crunch helium together to begin to form heavier elements like carbon and oxygen. According to the prevailing theory, the elements that will soon become the fundamental elements of life are being created in the burning out, collapsing, and re-formation of stars.
Our Solar System
Again, in the current model, our solar system forms about 4.5 billion years ago, about 9 billion years into the existence of the universe. Our Sun is thought to be a third generation star, meaning that a first star burned out and exploded. Then a second star formed with heavier elements in the mix. It burned out and exploded, creating all the elements we now know. Then that material coalesed around our Sun, Sol, with at least eight planets in tow.
The main feature of this model that could present a potential conflict with faith is the timeline. Those who take Genesis 1 to teach a full creation in six 24 hour days will object to a universe that is 13.5 billion years old. However, there are also interpretations of Genesis 1 that see no conflict here.
We will discuss various interpretations and science strategies in the next chapter. Apart from the timeline, nothing in this sequence seems intrinsically unbiblical or contrary to faith. Indeed, one could suppose that God himself was orchestrating these developments, as we will argue in the later section in this chapter on the Fine-Tuning argument.
[1] Alan H. Guth, “Inflationary universe: A possible solution to the horizon and flatness problems,” Physical Review D 23, no. 2 (1981): 347–356. He published a more popular version of his argument that same year as The Inflationary Universe: The Quest for a New Theory of Cosmic Origins (Basic, 1981).
[2] See Stephen Weinberg, The First Three Minutes: A Modern View of the Origin of the Universe (Basic, 1993).
[3] Deuterium is hydrogen with a neutron in the nucleus. Normally hydrogen has no neutrons. Lithium has three protons and four neutrons in its nucleus.
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