During a seminar I was leading on the existence of God, a Christian in the audience was outraged at two words I used.
“Big Bang!” he shouted. “There was no Big Bang! The Bible doesn’t say anything about it, and I believe the Bible. The Big Bang is just atheist propaganda!”
Eventually he let me explain why the Big Bang was actually good evidence for the existence of God. Indeed, perhaps seventy years ago the situation would have been reversed. If I had mentioned the Big Bang in a public seminar, an atheist might have said, “There wasn’t a Big Bang! The Big Bang is just religious propaganda!”
Beginning of the Big Bang
In the early twentieth century, the Belgian priest and physicist Georges LemaÎtre concluded that Einstein’s new theory of gravity, called general relativity, would cause a static eternal universe to collapse into nothingness. Since Einstein’s theory was sound, this only meant one thing: The universe was growing and had a beginning in the finite past.
Fr. LemaÎtre and Einstein would discuss the cosmic consequences of the theory while strolling the campus of the California Institute of Technology in Pasadena, California, and although Einstein was skeptical at first, in 1933 he proclaimed that LemaÎtre’s theory of an expanding universe was one of the most “beautiful theories he had ever heard” (John Farrell, The Day Without Yesterday, 115).
Fr. LemaÎtre called his theory “the primeval atom,” but another physicist, Fred Hoyle, mocked the theory with the term Big Bang. Hoyle believed that theories of the universe beginning to exist from nothing were “primitive myths” designed to put religion into science. Fr. LemaÎtre’s status as a Catholic priest did not help the situation.
In response to Fr. LemaÎtre, Hoyle argued for what he called the “steady state theory” of the universe. According to this theory, the universe existed eternally and has never rapidly expanded or changed. But two key pieces of evidence supported Fr. LemaÎtre.
Evidence for the Big Bang
In 1929, American astronomer Edwin Hubbell discovered that galaxies were moving away from each other at an increasingly faster rate, which is best explained by the Big Bang sending them flying away from each other at the beginning of time.
Then, in 1965, Bell Laboratory technicians Arno Penzias and Robert Wilson used radio telescopes to detect a faint, uniform “glow” of static coming from all directions of the sky. At first, they thought this glow was merely bird droppings contaminating the telescope! But after a thorough lens cleaning, the static turned out to be radiation in the form of microwaves coming from deep space.
According to the Big Bang model, right after the “bang” the universe was a white-hot ball of plasma before it cooled and formed stars and galaxies. Particles that had been flying around since the very beginning of time cooled and turned into microwaves, traveling to fill the whole cosmos. Today, this radiation is called Cosmic Microwave Background Radiation (or CMBR).
This discovery was so monumental that Penzias and Wilson won the Nobel Prize for it, and Fred Hoyle admitted it refuted his steady-state model of an eternal universe: “[It] is widely believed that the existence of the microwave background killed the “steady state” cosmology. . . . Here, in the microwave background, was an important phenomenon which it had not predicted” (Michio Kaku, Parallel Worlds, 69-70).
This discovery vindicated Fr. LemaÎtre’s primeval atom and made the Big Bang a well-established scientific theory. Today the Big Bang theory is called the “Standard Model” (or the Friedmann-LemaÎtre model) and has been the primary model of cosmic origins for more than forty years.
The movement of stars away from each other and the cosmic radiation throughout the galaxy provide almost indisputable evidence that the Big Bang did happen: not an explosion in space, understand, but an expansion of space (as well as time, matter, and energy) from an infinitely dense point called a singularity. According to renowned Tufts University cosmologist Alexander Vilenkin, “All the evidence we have says that the universe had a beginning” (Lisa Grossman, “Why physicists can’t avoid a creation event,” (New Scientist Magazine, Jan. 11, 2012).
A Big Crunch?
Some atheists say that the universe might expand from a Big Bang and then re-collapse into a “Big Crunch.” After the “crunch” back into the nothingness, the universe might expand again in another Big Bang. According to the cyclic model of the universe, this process will go on forever into the future and has gone on forever into the past.
But the cyclic model can succeed only if the density of matter in the universe is greater than what scientists call the critical density. If it is greater, then gravity will overpower matter and pull it back into a big crunch. But if the density of matter is less than critical density, then gravity won’t be strong enough to pull the matter back into a big crunch, and the universe will expand forever.
So, will there be a “Big Crunch,” or will the universe expand forever? It appears to be the latter, since so-called “dark matter” and “dark energy” make up 96 percent of the matter in the universe. This strange matter alone has enough mass and gravitational force to keep the universe expanding forever.
Victor Stenger writes in his book God and the Folly of Faith,“[M]ost cosmologists currently do not expect that the big crunch will happen. The best guess based on current observation and theory is that the universe is open; that is, it will expand forever” (205). After billions of years, the universe will cool as every star in the universe uses up the finite amount of nuclear fuel it has and burns out. Then the universe will reach heat death and become a cold, lifeless place that will never collapse into a “Big Crunch.”
But even if our universe did “bounce” from a previous big crunch, the evidence from physics shows that such a universe, in the words of Fr. Robert Spitzer, “could not have been bouncing forever” (New Proofs for the Existence of God, 27). That is because whenever a universe collapses or experiences a “Big Crunch,” an intense buildup of disorder is created that carries over into the next cycle. According to physicist Richard Tolman, this increased disorder would cause future big-bang cycles to be longer, because the energy being carried over after the big crunch creates more outward pressure in the next cycle.
What caused God?
Some atheists think they can refute this argument by asking, “If everything needs a cause, then what caused God?” The argument from the beginning of the universe, however, never says that everything requires a cause. It only claims that everything that begins to exist requires a cause for its existence.
Since we have good reasons to believe that the universe began to exist, then the universe requires an explanation for why it exists. God, on the other hand, never began to exist because he is eternal (he created time itself), and therefore God requires no cause for his existence. He has always existed; but the universe has not always existed.
If the universe began to exist, what was God doing during the eternity before the world began? St. Augustine confronted this question in the fifth century. His joking response was that for all eternity God was making hell for people who ask questions like this (Confessions, 229). His more serious response was that prior to the creation of the world there was no time. It makes no sense to ask what God was doing prior to the creation of the world, because the creation of the world included the first moment of time. Time can be a difficult thing to understand, but one common-sense view is to think of time as a measurement of change. If God existed in a changeless, perfect state without the universe, then our mental picture of a lonely God passing countless idle eons is a flawed one.
May the Force be with you?
Why not think the cause of the universe is some kind of force or law of nature instead of a person like God?
First, the forces we are aware of, like gravity, exist within the space-time universe, and so they could not be responsible for the creation of space and time.
Second, the cause of the universe could not be some impersonal force, because prior to the creation of the universe there could only exist a timeless, spaceless, unchangeable state of affairs (remember, time and space came into existence at the Big Bang). An eternal force can’t choose to make a non-eternal universe. Only a person can do that.
For example, imagine you had an eternal freezer, and inside of it was a tray of frozen water. If you could date the water, you would see that it had been frozen for all eternity, because the air in the freezer is always thirty degrees and the laws of physics are constant, so nothing can ever change. If, however, you found water that was only half frozen, you would conclude that someone chose to put the ice tray into the eternal freezer only a short time before. It could not have been in there for all eternity, because then the effect of frozen water would be as old as the cause, or the eternal freezer.
Likewise, if our universe were the product of a blind force or law, then we should expect that the effect of our universe would exist for as long as the eternal force existed. Since our universe is not eternal, it is reasonable assume that a personal, uncaused being chose to create a non-eternal universe.
Furthermore, our universe contains evidence of design that could only have been created by a being of considerable power and intelligence.
The grand design
In the past fifty years, scientists have discovered that there are a wide variety of constants and conditions that could have made up the laws of nature. Even a slight variation in many of the laws of nature would have spelled disaster for life as we know it. Here are just a few of them:
Weak gravitational force: Although gravity may seem like a very strong force because of its ability to hold all of us on the earth, in comparison to the other forces in nature, it is extremely weak. According to physicist Martin Rees, gravity is 1036 times weaker than competing forces within atoms (Just Six Numbers, 33-34). As a 2009 article in New Scientist Magazine put it, “The feebleness of gravity is something we should be grateful for. If it were a tiny bit stronger, none of us would be here to scoff at its puny nature” (“Gravity mysteries: Why is gravity fine-tuned?”, New Scientist Magazine, no. 2712, June 10, 2009).
If gravity were stronger, stars would burn out quickly, and the planets that orbited them would be tiny. Any life form on those planets would be crushed if it were larger than an insect, thus making the evolution of intelligent life almost impossible. New Scientist Magazine goes so far as to assert, “Only the middle ground, where the expansion and the gravitational strength balance to within one part in 1015 (or one part in a quadrillion) at one second after the big bang, allows life to form.”
Strong nuclear force: The strong nuclear force is what contains the protons inside atoms. Take two magnets and try to touch the positive ends of each magnet together. They repel, right? It requires strength to get them to touch. Much the same way, the protons in an atom have a positive charge, so we would expect them to fly away from each other. But the strong force holds them together.
So why does this force need to be fine-tuned? If the strong force were two percent weaker, hydrogen atoms would repel one another, and there would be only hydrogen atoms in the universe. But if the strong force was two percent stronger, then all of the hydrogen atoms would quickly attach to one another, and there would be only helium. Without free hydrogen, you can’t make atoms like H20, or water. This would make life’s existence highly unlikely, if not impossible (Rees, 54-55).
The expansion rate of the universe: The cosmological constant represents the strength of gravity in an empty vacuum of space. This constant also controls how fast the universe expands. Once thought to be zero, this constant is actually fine- tuned to the 120th power—a decimal point with 199 zeros and a one. In other words, the constant could have been 10120 times larger than a life-permitting value, and so there needs to be an explanation for the constant’s incredibly small, yet non-zero value. Alexander Vilenkin writes:
A tiny deviation from the required power results in a cosmological disaster, such as the fireball collapsing under its own weight or the universe being nearly empty. . . . This is the most notorious and perplexing case of fine- tuning in physics (Many Worlds in One, 10).
String theorist Leonard Susskind, a nonreligious scientist, as is Vilenkin, says that unless this constant was fine-tuned, “statistically miraculous events” would be needed for our universe to be life-permitting. He suggests that, in light of this, it is possible that an unknown agent set the early conditions of the universe we observe today (Lisa Dyson, Matthew Kleban, and Leonard Susskind, “Disturbing Implications of a Cosmological Constant”).
By chance alone?
Some people object that the fine-tuning of these constants, no matter how improbable, is nothing more than a lucky coincidence and should not be attributed to God. After all, if life could evolve by chance over billions of years, then why couldn’t the laws of physics be the result of chance as well?
The comparison does not succeed, because while life has billions of years to evolve on our planet, the constants and quantities in nature are a one-shot deal that came into existence in the first moments right after the Big Bang. They are like a tiny slot in a roulette wheel the size of the sun. There was only one chance to get the constants of physics just right; otherwise, the presence of life in our universe would have been impossible.
Another example shows why sheer chance is an unsatisfactory explanation. Imagine that you are playing poker with a friend and he gets a royal flush. You don’t question his apparent luck—until he wins ten hands in a row, all with royal flushes. Now you think he must be cheating, because that explanation is more probable than luck.
And yet the odds of our universe being finely tuned would be comparable to the odds of getting 50 royal flushes in a row! If we reject chance as an explanation for an improbable poker game, shouldn’t we reject chance as an explanation for an even more-improbable universe?
Just a coincidence?
One common response to this argument is the so-called weak anthropic principle, which states that if the universe weren’t finely tuned we wouldn’t be here to appreciate that fact, since the universe would not support intelligent life. Therefore, fine-tuning is nothing more than an anthropic (human) coincidence, because if it didn’t happen, we wouldn’t notice it.
The philosopher John Leslie rebuts this response by asking us to imagine being fired upon by fifty trained marksmen at a short distance. If every marksman missed, we wouldn’t dismiss such an extremely improbable event by saying, “Well, of course I’m alive. If the marksmen hadn’t missed then I wouldn’t be here to appreciate that fact.” Instead, it would be far more likely that the missed shots were part of a larger plan to let me live and not a product of chance (Universes, 13-14).
Was it God?
Why think the cause of the universe is the Christian God? Richard Dawkins writes in The God Delusion:
[T]here is absolutely no reason to endow the [first cause of the universe] with any of the properties normally ascribed to God: omnipotence, omniscience, goodness, creativity of design, to say nothing of such human attributes as listening to prayers, forgiving sins and reading innermost thoughts (77).
We can admit that philosophical arguments cannot demonstrate every truth about God’s existence. But they don’t have to. The different arguments for God’s existence can be compared to the individual strands of a rope. Individually, the strands cannot hold the entire weight of the argument (or prove a traditional God exists), but woven together the strands become a strong rope capable of performing such a task.
The strand involving the argument from the beginning of the universe doesn’t prove that God is good (that’s a job for the moral argument), but it can demonstrate other necessary parts of the case for God’s existence. For example, since the first cause of the universe was responsible for the existence of space and time, this cause must also be immune to the restrictions of space and time (that is, be immaterial and eternal). This means the first cause could not be a mere material object (like an alien) but must instead be a transcendent cause, or what most people call God.
In summary, the evidence from the origin of the universe and the laws of physics serves to confirm what the Psalmist proclaimed thousands of years ago: “The heavens declare the glory of God; the sky proclaims its builder’s craft” (Ps. 19:1).