A Philosopher Rejects the Multiverse but Embraces Mythology
The fine-tuning of our universe is, of course, widely seen as providing evidence for intelligent design. And rightly so, as Stephen Meyer shows in Return of the God Hypothesis. This, however, leaves many a scholar in a quandary. Thus, in a recent article at The Conversation, Durham University philosopher Phillip Goff presents his views on the fine-tuning of the physical parameters, the multiverse postulate, and cosmic purpose.
Goff acknowledges the significance of the physical constants of the universe and their fine-tuning for life.
One of the most startling scientific discoveries of recent decades is that physics appears to be fine-tuned for life.
Physicist Paul Davies, an agnostic, also acknowledges the reality of fine-tuning and its significance for our lives.
If almost any of the basic features of the universe, from the properties of atoms to the distribution of the galaxies, were different, life would very probably have been impossible… On the face of it, the universe does look as if it had been designed by an intelligent creator.1
Goff’s example of fine-tuning echoes the Goldilocks analogy that Davies uses:
To allow for the possibility of life, the strength of dark energy had to be, like Goldilocks’s porridge, “just right.”
A God-Substitute
As Goff seeks to interpret the evidence, he reveals the philosophical discomfort that fine-tuning evokes in those who prefer a naturalistic explanation for the universe. In principle, science usually proceeds along these lines: naturalistic explanations for the phenomena of our universe are indeed appropriately sought first. The multiverse scenario, however, has ballooned up to serve as a God-substitute for those with a worldview excluding the possibility of metaphysical causes.
Some physicists aren’t too bothered by the seemingly fine-tuned cosmos. Others have found comfort in the multiverse theory. If our universe is just one of many, some would, statistically speaking, end up looking just like ours.
Goff takes issue with the current default understanding of the multiverse. The attempted rebuttal to the fine-tuning evidence typically proceeds from the following assumption:
If there are enough universes, with different numbers in their physics, it becomes likely that some universe is going to have the right numbers for life.
Multiverse scenarios assume that a putative universe-generating mechanism endows its offspring with physical laws and parameters spanning a wide spectrum of possibilities. However, this notion flies in the face of what we observe as a general feature of the physical realm.
In nature, chance interactions do not necessarily lead to an unlimited variety of outcomes but tend to produce limited variation. For example, throughout the 13.8-billion-year history of the universe, only a finite number of elements (about 94) have ever formed by natural processes. This limitation is a result of constraints on nature due to the laws of physics. The limitations imposed by those laws will prevent the natural formation of elements with, say, 200 protons, or an isotope of carbon with 53 neutrons — no matter how long we might wait.
A God-Substitute
As Goff seeks to interpret the evidence, he reveals the philosophical discomfort that fine-tuning evokes in those who prefer a naturalistic explanation for the universe. In principle, science usually proceeds along these lines: naturalistic explanations for the phenomena of our universe are indeed appropriately sought first. The multiverse scenario, however, has ballooned up to serve as a God-substitute for those with a worldview excluding the possibility of metaphysical causes.
Some physicists aren’t too bothered by the seemingly fine-tuned cosmos. Others have found comfort in the multiverse theory. If our universe is just one of many, some would, statistically speaking, end up looking just like ours.
Goff takes issue with the current default understanding of the multiverse. The attempted rebuttal to the fine-tuning evidence typically proceeds from the following assumption:
If there are enough universes, with different numbers in their physics, it becomes likely that some universe is going to have the right numbers for life.
Multiverse scenarios assume that a putative universe-generating mechanism endows its offspring with physical laws and parameters spanning a wide spectrum of possibilities. However, this notion flies in the face of what we observe as a general feature of the physical realm.
In nature, chance interactions do not necessarily lead to an unlimited variety of outcomes but tend to produce limited variation. For example, throughout the 13.8-billion-year history of the universe, only a finite number of elements (about 94) have ever formed by natural processes. This limitation is a result of constraints on nature due to the laws of physics. The limitations imposed by those laws will prevent the natural formation of elements with, say, 200 protons, or an isotope of carbon with 53 neutrons — no matter how long we might wait.
Unlimited Physical Outcomes?
In light of all we know of this universe, even if a multiverse of other universes exists, it’s unreasonable to suppose that a near-infinite variety of physical outcomes will result within those universes.
Goff acknowledges that the idea of the multiverse is consistent with the physics of cosmic inflation, but he denies its utility as a valid explanation for the specific fine-tuning in our universe.
The scientific theory of inflation — the idea that the early universe blew up hugely in size — supports the multiverse. If inflation can happen once, it is likely to be happening in different areas of space — creating universes in their own right. While this may give us tentative evidence for some kind of multiverse, there is no evidence that the different universes have different numbers in their local physics.
When this particular universe was created, as in a die throw, it still had a specific, low chance of getting the right numbers.
Limited variation in physical parameters is to be expected. Why, then, would this particular universe, the only observable one, have so many parameters fine-tuned to a razor’s edge in support of life?
Goff identifies an additional philosophical error committed by those who appeal to the multiverse.
Experts in the mathematics of probability have identified the inference from fine-tuning to a multiverse as an instance of fallacious reasoning…. Specifically, the charge is that multiverse theorists commit what’s called the inverse gambler’s fallacy.
They think: “Wow, how improbable that our universe has the right numbers for life; there must be many other universes out there with the wrong numbers!”
A low-probability event is not explained by postulating a fictitious multitude of other players in the game. The only game in town is our observable universe, and its highly specific suite of parameters, if naturally occurring, must be explained by what we know exists in nature, not by appealing to what cannot be observed in nature.
The Anthropic Principle
Goff also addresses another common argument made by multiverse proponents:
At this point, multiverse theorists bring in the “anthropic principle” — that because we exist, we could not have observed a universe incompatible with life.
Logically, who can argue with this? If the universe’s parameters didn’t allow life, nobody would be here to discuss the issue, or read articles about it, either. However, this dismissal glosses over a fine point — the universe must be tuned to allow life, or else we wouldn’t be here, but no stretch of logic demands that it be exquisitely fine-tuned for life. Since the tuning for life is balanced on such a sharp knife-edge, intellectual curiosity leads us to legitimately suspect far more at work than an uninteresting axiomatic requirement for our existence.
If we hold that the constants of our universe were shaped by probabilistic processes — as multiverse explanations suggest — then it is incredibly unlikely that this specific universe, as opposed to some other among millions, would be fine-tuned.
And Now, the God Hypothesis?
Granting that fine-tuning is real, but philosophically rejecting the multiverse as a cure-all for naturalism and its woes, is Goff led to accept “the God hypothesis”? No. He instead idolizes the universe itself, imagined as a sort of fertile incubator for life, pregnant with fine-tuning and the potential for vivification.
The conventional scientific wisdom is that these numbers have remained fixed from the Big Bang onwards. If this is correct, then we face a choice. Either it’s an incredible fluke that our universe happened to have the right numbers. Or the numbers are as they are because nature is somehow driven or directed to develop complexity and life by some invisible, inbuilt principle.
An important point from information theory, however, is that no degree of fine-tuning of physical parameters, so that life is allowed to exist, would by its nature drive life to develop. The material of the physical universe is influenced by just four fundamental forces of nature, and aside from the weak force (involved in radioactive decay), these forces do nothing more than exert an indiscriminate push or pull.
Ascribing sentience or cosmic purpose to forces or the particles on which they act is to step out of the realm of science into the realm of myth-making. The purpose we observe in the universe is incompatible with inanimate particles but it is totally consistent with an ultimate cause whose attributes transcend the highest categories of human characteristics. However, there is a long history of humans who, faced with the idea of a creator, would prefer to say to a rock, “You gave me birth.”2
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