By Scott Bonham
I had a strange experience when I took an introduction to quantum mechanics course as an undergraduate physics major. While my homework and exam scores said I was doing well in the class, I felt like the course didn’t make any sense to me, and I had this nagging feeling of being lost. Years later, while studying cognitive science (my current scholarly focus is on the teaching and learning of physics), I developed a better understanding of that experience, arising from how our minds work when encountering something as different as quantum reality.
A key principle in learning theory is that we learn by making mental connections between existing knowledge and new information. At the cellular level, learning involves neurons making, breaking, or modifying connections with others. At the cognitive level, information that a person can connect to their already existing knowledge structures is far more likely to be retained (1). A significant challenge in studying quantum mechanics is that it describes a reality so different from that of everyday experience that it is hard to make meaningful connections. My feeling of lostness as an undergrad reflected my struggle to make those connections to my existing knowledge structure. Eventually, the unease subsided as I started to build a new quantum mechanics knowledge structure with only tenuous connections to the rest of my knowledge. Although I even developed a theoretical quantum model as part of my doctoral work to explain my electron diffraction results, even today I would still rate my conceptual grasp of quantum mechanics as less solid than other areas.
The struggle to relate quantum reality to existing, macroscopic knowledge lies behind the nearly four hundred year-old and sometimes quite bitter scientific debate over whether light is a particle or a wave (2). That question helped start the infamous life-long feud between Isaac Newton and Robert Hooke (3). Despite my introductory physics students parroting their high school physics knowledge that light is both a wave and a particle, those are two completely different things in the macroscopic world we live in. Particles (think tennis balls) are things that exclusively occupy a particular space and must be added or subtracted by integral numbers. A wave (think ripples or football stadium waves) is a collective motion by a lot of something. It can be made larger or smaller by an arbitrary amount, and upon meeting another wave, one simply passes through the other, the motion at a given point being the sum of the two waves. In our everyday world, particles and waves are mutually exclusive categories of phenomena.
Thus it is no surprise that for centuries some of the best scientific minds debated whether light was a wave OR a particle. There was significant resistance to Albert Einstein’s quantization of light; ten years after it was first published, Robert Millikan insisted that the idea was “wholly untenable,” despite having just experimentally confirmed (against his expectations) Einstein’s photoelectric equation. It took nearly a decade more and mounting experimental evidence to force the scientific community to finally accept that light and subatomic particles exhibit both wave and particle properties (4).
Richard Feynman once remarked, “I think I can safely say that nobody understands quantum mechanics” (5). If Feynman didn’t understand quantum reality, who can? That inability is a function of how our minds work. We are always connecting new information to old, using our existing categories—perhaps modifying them some—to label and organize what we are learning. But the quantum realm is just too different to fit the everyday categories we have developed over decades of life. The best our limited human minds can do is to hold two seemingly contradictory ideas in tension as an approximation to a reality that is radically different from that in which our understanding developed. And if our limited human minds struggle to understand the quantum realm, what about other radically different realms of reality? I believe that God’s nature is something far more subtle and profound than creedal statements of the Trinity—one being in three persons—but that is simply the best approximation that our human minds can grasp given the categories we have developed living in a world where each person corresponds to a distinct physical being.
Ironically, as the scientific community finally came around to accept the quantization of light, Einstein pushed back against its implications of randomness in nature, declaring, “God doesn’t play dice.” Randomness and chance have been a source of tension between science and faith for many years. But let’s go back to our mental categories—exactly what do we mean by “chance”? In everyday use, it usually indicates something without purpose or intentionality, e.g. “I ran into a friend by chance.” Richard Dawkins and company point to randomness in evolution and other sciences and confidently proclaim there is no design or purpose in the world. In a narrow sense, they are absolutely correct; the study of evolutionary biology or cosmology reveals no evidence for design or purpose in the world. But then again, neither will one find design or purpose studying organic chemistry, nuclear physics, karst geology, stellar astronomy, or any other science. Science doesn’t study purpose. Science describes what is, not goals or intentions. The inability to see bacteria through a telescope proves nothing about their existence or lack thereof.
In that case, what does “chance” mean in a science context? At least in my discipline (physics), it means indeterminacy, the inability to predict the outcome of an interaction based on the initial state. Classical physics is determinate. It is possible (at least in principle) to predict exactly how a situation will evolve given full information about it. But seldom do we have full information even in a controlled experiment. Sometimes there are just too many things to keep track of, like all the air molecules in a container. Sometimes the system is too sensitive to slight differences in initial conditions, as in complex systems like weather. Sometimes, it is intrinsically impossible to obtain full information about a situation, as in quantum mechanics. Chance therefore means that our knowledge and processing capacity is too limited to predict the outcome in a particular situation. Note that the implication is that indeterminacy is in the mind of the predictor. Most of us will shuffle a deck of cards to put it in random order. But given enough practice and a deck in good condition, it is possible to execute a perfect ruff, which will leave the cards in perfect (though a different) order.
Our experience of chance arises from our limitations—fundamental or otherwise—in being able to determine the outcome of a situation. God, though, does not share our limitations. He can have perfect knowledge without having to measure things. His reasoning capacity is not limited like ours. He has an existence that is outside of and pre-dates matter, space, and time. He does not have to manipulate individual pieces to construct a whole. While the outcome of an individual photon going through double slits or an individual mutation are unpredictable to us, the sum of millions of photons or the different ecological niches organisms occupy in a given environment do show us regular, predictable behavior. What is God’s experience in interacting with the “chance” that is around us? That is hard to say. All of our speculation is built upon the categories we have developed out of everyday human experience that is vastly different from His. Thus, when we see randomness and chance in the world around us, it is more a reflection of our limited human minds than anything else. But “’my thoughts are not your thoughts, neither are your ways my ways,’ declares the Lord” (6).
Particles and waves. One God in three persons. Chance and design. These seem to be contradictions to human minds that developed reasoning abilities in a macroscopic world inhabited by physical, time-bound beings. But quantum mechanics and scripture provide pointers to a reality that is greater than and in some ways quite different from that of everyday experience. Our minds are finite and shaped profoundly by our life experiences. God is not. Just because we don’t understand something doesn’t make it untrue; sometimes the best we can do is hold fast to the tension between two seemingly contradictory ideas. Chance and design are a part of God’s plan.
(1) National Research Council, How People Learn: Brain, Mind, Experience, and School, John D. Bransford et al, editors. National Academy Press, Washington D.C., 1999.
(2) Olivier Darrigol, A History of Optics: From Greek Antiquity to the Nineteenth Century. Oxford University Press, Oxford, 2012.
(3) Richard S. Westfall, Never at Rest: A Biography of Isaac Newton. Cambridge University Press, Cambridge, 1983.
(4) Abraham Pais, Subtle Is the Lord: The Science and the Life of Albert Einstein. Oxford University Press, Oxford, 2005.
(5) Richard P. Feynman, The Character of Physical Law. M.I.T Press, Boston, 1967.
(6) Isaiah 55:8, New International Version, International Bible Society, 1984.
Scott Bonham is an Associate Professor of Physics at Western Kentucky University. His professional work is in physics education research with a focus on student understanding and skills in scientific communication/argumentation and the history/ philosophy of science, as part of a calling to build connections and understanding between science, education, humanities, culture and faith.