2.10.C — What Are the Leading Explanations for the Fine-Tuning of the Universe?
(Fine-Tuning and Cosmic Order)
Bearings: Where do we stand right now?
In the previous essays we observed that several features of the universe appear to operate within narrow ranges that allow stars, chemistry, and complex structures to develop. Cosmologists have studied the strengths of physical forces, the rate of cosmic expansion, and the early conditions of the universe, noting that small differences in these factors would produce a dramatically different cosmos. Those observations naturally raise another question. If the universe displays this kind of balance, how should it be explained? Scientists and philosophers have proposed several possible answers. Each approach attempts to account for the order observed in the universe.
What Are the Leading Explanations for the Fine-Tuning of the Universe?
Chance
One explanation is simple chance. According to this view, the physical constants of the universe happened to fall within life-permitting ranges by coincidence.
Supporters of this perspective point out that improbable events can occur. Given enough time or possibilities, unlikely outcomes may eventually appear. From this perspective, the universe we observe is simply the one that happened to arise.
Some physicists acknowledge that the life-permitting nature of the universe appears unusual, yet they regard it as the product of chance within the broader possibilities of physical reality.¹
Necessity
Another explanation proposes that the universe could not have been different. In this view, the laws of physics may ultimately require the constants we observe. If the structure of reality itself demands these values, then the universe would necessarily appear as it does.
This possibility is sometimes connected to the search for a unified theory of physics that explains why the constants of nature possess their particular values. If such a theory exists, it might reveal that the universe could not operate in any other way.
Physicists continue to explore this possibility, although a complete explanation has not yet been discovered.
Many Universes
A third explanation involves the idea of multiple universes. Some cosmological theories propose that our universe may be one among many, each possessing different physical constants or conditions.
In such a scenario, most universes would not support complex structures or life. However, if a vast number of universes exist, it would not be surprising that at least one contains the conditions necessary for observers to exist.
The physicist Stephen Hawking noted that certain cosmological models allow for many possible universes with different physical properties.² This idea attempts to explain fine-tuning without requiring that the universe was intentionally structured for life.
Intentional Order
Another perspective suggests that the observed structure of the universe reflects intentional order. In this view, the balance of physical laws is consistent with the idea that the universe was designed to allow complexity and life.
Some scientists who have studied the fine-tuning of cosmic conditions have remarked on how unusual the balance appears. Astronomer Robert Jastrow once commented that the more scientists investigate the universe, the more they encounter questions that reach beyond purely physical explanations.³
This perspective does not claim that science can prove design in a mathematical sense. Instead, it suggests that the order observed in the universe may be consistent with the idea of purposeful creation.
Creation and the Interpretation of Order
Scripture approaches the question of cosmic order from a theological perspective. The biblical writers understood the structure of the world as reflecting the work of its Creator.
The psalmist expresses this idea simply:
“The heavens declare the glory of God,
and the sky above proclaims his handiwork.”
— Psalm 19:1 (ESV)
This statement does not attempt to describe physical constants or cosmological models. Instead, it reflects the belief that the order visible in the universe points beyond itself toward its Maker.
Personal Reflection Questions
Understanding
What are the main explanations proposed for fine-tuning, and why does each attempt to account for the same evidence?
Examination
Do I favor an explanation because it best fits the evidence, or because it feels safest or most familiar?
Am I willing to think carefully about competing explanations without fear?
Before We Head Out: What Have We Learned, and Where Is It Leading Us?
Scientists and philosophers have proposed several explanations for the finely balanced conditions observed in the universe. Some attribute these conditions to chance. Others suggest that the laws of physics may require them. Still others propose the existence of many universes with different physical constants. Another possibility is that the order of the cosmos reflects intentional design. Scripture approaches the question by presenting creation as a work that reveals the power and wisdom of God (Psalm 19:1, ESV). In the next section we will move from the structure of the universe to another feature of human experience—moral awareness—and consider what it suggests about the nature of reality.
Footnotes
- Steven Weinberg, Dreams of a Final Theory (New York: Pantheon Books, 1992).
- Stephen Hawking and Leonard Mlodinow, The Grand Design (New York: Bantam Books, 2010).
- Robert Jastrow, God and the Astronomers (New York: W.W. Norton, 1978).