A Fine-Tuned Universe is described using seven categories: The Initial Condition of the Universe, Initial Entropy, the Cosmological Constant, the Mysterious Presence of Carbon and three Fundamental Forces required to form carbon molecules.
What is a Fine-Tuned Universe?
For many years I’ve been aware that there were important arguments about the apparent “fine-tuning” of the universe. However, the concept was never clearly explained to me, even though I had the impression that it was something fundamental that I really ought to understand.
Since ancient times, people have gazed into the heavens or looked at the abundance of beauty and life on earth derived from a sense of intelligence behind the creation of the universe – they saw it as evidence of God. However, in my life, I learned that the universe originated from a Big Bang some fourteen billion years ago. When I look at the stars at night, I imagine what it might be like to be a creature living on a molecule inside an exploding firework. I can see the stars expanding in every direction away from me in a spectacular show of color and sound. In other words, I had a secular (and I would assume common) perspective of the universe shared by many people in the West that does not rely on a transcendent and personal God to make it all happen.
Nevertheless, from the threads I gathered, it began to sound like the fine-tuning meant that it was highly improbable that our universe could be here at all. It made me wonder what kind of odds we were talking about. I became curious, and my radar antennae reached out to learn more. Unfortunately, I typically found extremely dense texts that dove deep into the mathematics, history, and personalities of individual scientists who made significant contributions. It felt like entering a war zone as competing scholars couched their arguments carefully to anticipate or counter the refutation they expected as incoming fire from their colleagues.
So over the years, I picked up parts and pieces of arguments, just enough to give me a sense that fine-tuning was critical to understanding the battles underlying our competing worldviews. So you can imagine my relief when I came across an author who was able to provide me with an overall picture of the parameters involved. Stephen Meyer (2021) dedicated several chapters to “The Goldilocks Universe” and the extreme fine-tuning it requires. Still, the arguments were very detailed and dense, and I found I could not have a conversation about it with my family or friends, even though I was powerfully moved by what I had read.
So you might say that I wrote this essay primarily for myself. I just summarized Meyer’s work into seven categories of fine-tuning necessary for the existence of our universe and the life inside it: the Initial Condition of the Universe, Initial Entropy, the Cosmological Constant, the Mysterious Presence of Carbon and three Fundamental Forces required to form carbon molecules. This short essay is meant to be more of a quick-reference guide than an academic treatise. If you are so inclined, there is a universe of scholarly articles on each of these subjects. But I prefer to consider them all together and to reflect on how all of these examples of fine-tuning interact:
Initial Condition of the Universe
We live on a planet with a stable orbit around the sun, a sun positioned in the arm of a beautiful spiral galaxy, and a universe filled with billions of galaxies like ours. But all this is only possible because at the instant of the Big Bang, the universe’s initial conditions allowed for precisely those structures to emerge.
Had the initial conditions been just slightly different, matter would clump too densely, and the universe would be just a mass of massive, uninhabitable black holes.
Tilt the balance too far in the other direction, and the universe would have diffused to such an extent that no large-scale structures of matter would exist at all.
Paraphrased from: Meyer, S. (2021) Return of the God Hypothesis. (pp. 146-147)
The Big Crunch - Initial Entropy
If the initial conditions leading to the emergence of our stable universe are improbable, just how improbable are they? Oxford physicist Sir Roger Penrose wanted to gain a measurement of the initial arrangement of matter and energy. To do that, he chose to calculate different states of entropy.
Entropy measures the amount of disorder in a system. More entropy means more disorder in the universe, and black holes represent maximum entropy and maximum disorder. Less entropy means more order in the universe, and stable galaxies represent the extremely low entropy system we enjoy.
Penrose calculated all possible ways that matter and energy could be configured in the initial conditions that would result in a black-hole dominated universe and compared them to the much smaller number of ways matter and energy could be configured to generate a stable universe like ours.
The number Penrose came up with is called a hyper-exponential. It is the number ten, raised to the tenth power (or ten billion), raised again to the 123rd power. To give some perspective, if you tried to write out that number, you would have more zeros than elementary particles in the entire universe. The human language does not possess words that even begin to describe the exquisite degree of initial entropy fine-tuning required to form our universe.
Paraphrased from: Meyer, S. (2021) Return of the God Hypothesis. (pp. 148-151)
Expansion Rate of the Universe / Cosmological Constant
Penrose chose to examine the odds of the universe clumping into black holes. But what about the other side of the balance, a universe that spreads out so much that it diffuses into a complete lack of structure?
Our stable universe depends crucially on its expansion rate. The density of our universe at one nanosecond after the beginning had to have a precise value of ten, raised to the 24th power kilograms per cubic meter. Galaxies would never have developed if the density were larger or smaller by only one kilogram per cubic meter.
The cosmological constant is a number that Albert Einstein originally added to his field equations of general relativity. Later, he removed it. Much later, he revived the cosmological constant and added it back in as the energy density of space. The cosmological constant is the outward expansion of space that opposes gravitational attraction. This is another number that represents the fine-tuning of the universe. While there are different estimates for the cosmological constant, physicists generally agree that it is no less than one part in ten, raised to the 90th power.
Again, human language, and even human imagination, often fail to grasp the magnitude of the odds against our universe forming the way it did. Consider the visible universe with about 200 billion galaxies, each with 100 billion stars; if you could travel instantly anywhere in the universe and examine any subatomic particle, your odds of finding a specially marked particle (one chance in ten, raised to the 80th power) are still 10 billion times better than the probability (one chance in ten, raised to the 90th power) that the universe would have happened upon the cosmological constant necessary for life to exist in the universe.
Paraphrased from: Meyer, S. (2021) Return of the God Hypothesis. (pp. 151-152)
Extreme Fine-Tuning Necessary for Life
There are many examples of fine-tuning, but not all of them apply to the creation of the universe. The odds of life emerging from matter are also wildly improbable.
Mysterious Presence of Carbon in the Universe
The universe contains a surprising amount of carbon, and carbon has unique features that make it suitable for forming long-chain molecules capable of storing and processing genetic information. Carbon-based life is the only known form of life in the universe. In the 1950s, astrophysicist Sir Fred Hoyle pioneered research on how nuclear reactions within stars generated chemical elements, including carbon. He envisioned neutrons and protons (known collectively as “nucleons”) colliding and fusing in the intense gravitational wells at the center of stars.
However, fusing beryllium-8 (with four neutrons and four protons) with helium (with two neutrons and two protons) to form carbon-12 (with six neutrons and six protons) required passing through an unstable state where particles contain nuclei with five total protons and neutrons. This barrier between smaller, lighter elements and heavier elements is known as the “5-nucleon crevasse.” The barrier represents molecules with incredibly short half-lives of about one trillionth of one trillionth of a second. There is simply not enough time for particles to form before they are obliterated.
It was a cosmic dilemma. The odds of just the right collision that skipped over the 5-nucleon crevasse were extremely unlikely. Yet, the abundance of carbon in the universe indicated that some other factor was at work.
Hoyle speculated that if a higher-energy version of carbon-12 existed, it would provide the environment necessary (according to quantum physics) to allow beryllium-8 to fuse readily with helium. He calculated that the precise excitation state would have to be 7.65 megaelectron volts (MeV) more than the common carbon-12. In a stunning example of theory leading to discovery, Hoyle persuaded the Kellogg Radiation Laboratory to search for, and eventually find, a form of carbon with exactly the higher energy levels (or “resonance”) he predicted. Hoyle had correctly identified the incredible degree of fine-tuning required to solve the problem.
Paraphrased from: Meyer, S. (2021) Return of the God Hypothesis. (pp. 131-135).
Three Fundamental Forces in Nature
Hoyle’s prediction was amazing. However, rather than resolving the problem, Hoyle opened the door to even more forces that require extreme fine-tuning to form carbon. While by no means an exhaustive list, three fundamental forces in nature that require fine-tuning to produce carbon are; the gravitational force (G), the electromagnetic force (EMF), and the strong nuclear force (SNF):
If the gravitational (G) force were weaker, smaller atoms would not be able to combine into larger carbon atoms. It would also prevent stars from forming supernovae with the capacity to eject the elements necessary for life into the universe. Physicists have determined that the value of the gravitational force is fine-tuned to one part in ten, raised to the 35th power in relation to the ranges of all possible gravitational forces (i.e., in possible alternate universes).
The electromagnetic force (EMF) attracts particles with opposite charges and repels those with the same charge. The strong nuclear force (SNF) is an attractor that holds protons and neutrons together. Both EMF and SNF must have precise strengths (within about .5% - 4% of their current levels) to make carbon production possible.
There are many other parameters that require fine-tuning to make life possible in the universe. Cosmologists and physicists have found more than a dozen highly improbable “parameters” that must be met for life to exist.
Paraphrased from: Meyer, S. (2021) Return of the God Hypothesis. (pp. 136-139).
What is even more remarkable when one stops to consider the ramifications is that all of these mind-blowingly improbable parameters must be met ALL AT THE SAME TIME. You would be more likely to win the lottery over and over again, day after day, for a thousand years, than for our universe to form. When people speak of the emergence of a fine-tuned universe, understand that mere words cannot begin to describe the razor’s edge of probability that allows us to exist.
So now, when I look into the night sky, I no longer think, “Well, science has got this all figured out.” Instead, now that I understand the odds, I experience a mind-shattering physical reaction. “How could all this be possible?” It seems to me now that evidence for God has been there all along, surrounding us at each moment and from every direction. It is a powerful experience of what Christians call General Revelation.
I know that with that last sentence, I will lose some readers. If the vulgar and personal attacks from the social media sites that I post on are an accurate indication, there is an intense and existential bias towards anyone who dares attempt to combine the “old superstitious religions” with any form of “pure science.” However, my ongoing work exploring various worldviews informs me that a simple dichotomy between religion and science is a straw-man argument:
Christian and Islamic Theists, as well as Deists to a degree, can accept the notion of a transcendent intelligence behind the creation of the universe.
In contrast, Naturalists, Nihilists, and Existentialists must believe that no god exists in order for their philosophies to work. If God exists, it upends their entire belief system. So, it comes as no surprise when they level irrational vitriol and personal attacks. The irony is that it is their own scientists (mostly) that have discovered the degree of fine-tuning necessary for the formation of the universe and the life within it. It bedevils them, forcing them to contemplate more complex theories (such as the multiverse theory) to explain what they have found. If you are in this category, please remember that I am not a scientist; I didn’t discover this stuff! I’m just reporting on what I’ve learned. Consider aiming your wrath at those who are responsible for calculating the improbability of it all.
There are other categories of worldviews with very different reactions to the idea of a fine-tuned universe. Those with New Age beliefs tend to truly syncretize ancient and modern into a wide variety of pseudo-scientific theories and propositions. Meanwhile, the Eastern Pantheistic Monist dismisses the entire debate as shadows chasing shadows; they have an anti-rationalist perspective in which all the cosmos, including its apparent fine-tuning, is just an illusion without inherent meaning. Finally, the Postmodernist couldn’t give a damn. They become bored with the whole conversation unless it provides them with some leverage to gain something they want.
For myself, I’m storing this essay in my Emergentism Curated Library for future reference. As I suspected, the fine-tuned universe is a massively important concept that will profoundly influence every aspect of my work. What were the odds of discovering that?