I recently watched a new video making the rounds on the internet, by Brian Keating, Professor of Physics at the University of California, San Diego. It is titled “What's a Greater Leap of Faith: God or the Multiverse?”
What is “fine-tuning”? What is the “multiverse”?
In the video, Professor Keating introduces the scientific concept of fine-tuning and the basics of one of the multiverse theories, the inflationary model. This part of the video is a good visual introduction; you can also read more on our Common Question. In brief, the fine-tuning argument points to several physical properties of our universe, and notes that they are set to values that are just right to form atoms, stars, planets, and life. If the values were even slightly different, life could not form or survive in the universe. When viewed through the eyes of Christian faith, we see God crafting and sustaining a universe to fulfill his purpose of making a home for us.
The multiverse refers to a model where our universe is one of many universes, and each of the universes has different physical properties. Yes, this is a bizarre idea! But bizarreness alone is not reason to reject it. (Lots of properties of elementary particles are bizarre—like quantum tunneling—but have been confirmed over and over in the lab.) If the multiverse model were correct, some versions of the fine-tuning argument would be undercut. Our universe would be one of many, and it would not be so surprising to find ourselves in one of the few universes that were well suited for life—we could not survive in the others.
For atheists only?
Sometimes people describe the multiverse or other explanations for the beginning of the universe as if these were replacements for God. In a 2013 lecture, renowned physicist Stephen Hawking said, “A combination of quantum theory and the theory of relativity would better explain our existence than divine intervention.” This is a common refrain in videos and popular books about cosmology, focusing on these scientific theories primarily as a way to eliminate God.
If the multiverse idea were merely a shorthand for an atheistic worldview, then “God or multiverse” would be an appropriate question—we would be comparing metaphysical commitments in both cases. However, Keating misportrays an entire scientific community as being motivated primarily by an anti-God bias. While this may be true for some individual scientists, he portrays the multiverse only as an alternative to God and a way to get around the fine-tuning argument.
“Multiverse” actually refers to something much more substantial, in fact to several distinct scientific models. Many of those models arise out of theoretical physics and cosmology and have a rich mathematical basis. Moreover, the leading models were not built to address fine-tuning or multiple universes, but to better understand properties in this universe: the string theory multiverse was developed to bring together gravity and particle physics, and the inflationary multiverse was developed to explain the nearly uniform temperature and flat geometry of our universe. In both cases, the theory naturally led to ideas about many universes beyond our own. The “multiverse” is far more than a weird atheist idea, but studied by serious scientists, including some Christians. And multiverse theories do not eliminate fine-tuning; the multiverse would still need some parameters to be fine-tuned to produce fruitful universes.
While the multiverse idea is strange and very difficult to test, let’s keep considering it. To simply dismiss the multiverse as an atheist alternative to God is to dismiss a rigorous, mathematical structure that is driven by curiosity about the nature of matter and gravity and our universe. If you want to reject the multiverse, you would need to develop another theory that explains quantum gravity or the uniform temperature of our universe without predicting multiple universes.
Not God “or” the multiverse
Since some multiverse theories have a genuine connection to successful science of our universe, we need to take more care in how we talk about them in relation to God. Posing the issue as “God or the multiverse?” mixes two categories, a bit like asking “God or electricity?” Such either/or statements introduce a fundamental mismatch, setting up God as an alternative to a scientific theory. In Christian doctrine, God is never an alternative to a scientific model! God is the source of all that is, the one who creates and actively sustains every physical process. And Christians believe this, both when the physical process is understood scientifically and when it is not.
Unfortunately, the video never questions this underlying mismatch. It assumes, right along with many atheists, that “God” is in opposition to a potential “multiverse.” Christian physicists who do research in this area believe that if the multiverse exists, the multiverse would be created by God.
As Christians, we worship God as the Creator of all. When a scientific model is well understood, like electricity, we praise God for the chance to “think his thoughts after him” (as astronomer Johannes Kepler supposedly said). When the natural process isn’t understood, Christians are filled with curiosity to figure out how God went about doing it.
Let’s stay curious
As my friend and fellow Christian astronomer, Jeff Zweerink of Reasons to Believe, writes:
“Whether the multiverse proves true or false substantially affects none of the fundamental Christian doctrines. For this reason, it is important for believers to differentiate between multiverse models that advocate strict naturalism and models that promote the Creator. Rather than raising a battle cry against the concept of the multiverse, or writing it off as unfounded anti-biblical nonsense, it would behoove Christians to understand why people (scientists and others) find multiverse such an attractive explanation for the observable universe” (Who’s Afraid of the Multiverse, pg.49-50, emphasis original).
As Christians, let’s not set up a false dichotomy of God or multiverse. Instead, let’s stay curious about the many aspects of the universe we don’t understand and the bizarre properties it might have. Let’s counter atheists who say the multiverse—or any scientific explanation—is a replacement for God. Let’s ponder the potential theological implications of a vast multiverse. And through it all, let’s affirm God as the loving and faithful Creator of every aspect of his amazing creation, whether we understand it or not.