Quantum Physics and Theology: An Unexpected Kinship
By John Polkinghorne (Part 2a) — Comparative Heuristics
We are reviewing the book, “Quantum Physics and Theology: An Unexpected Kinship” by John Polkinghorne. Today we will look at the first part of Chapter 2- Comparative Heuristics. One of the lessons that quantum science teaches us about physical reality is that its character is frequently surprising. As a consequence, scientists who are carefully reflective don’t just instinctively ask the question, “Is it reasonable” as if they were confident beforehand what shape rationality had to take. Instead, the truth-seeking scientist may ask, “What makes you think that might be the case?” We’ve already seen how “unreasonable” the nature of light, in classical Newtonian terms, turned out to be. John says:
If you examine what Thomas Young had discovered about diffraction phenomena, and what Albert Einstein had to say about the photoelectric effect, you will be forced to take seriously the seeming paradox of wave/particle duality. In an analogous way, the writers of the New Testament were forced to affirm the even more perplexing fact of their encountering qualities both human and divine in their experience of Jesus Christ… Neither in physics nor in theology can one remain content with accepting the brute fact of the surprising character of reality. There has to be a further struggle to set this new knowledge in some deeper context of understanding.
Polkinghorne definitely believes that Christian thinking had to explore how the lordship of Christ related to the fundamental lordship of the God of Israel. He believes it was a journey of theological exploration that led the Church eventually to trinitarian and incarnational belief. He also believes that it is fruitful to pursue further the analogies discernable between these two forms of enquiry, even though they engage very different subject material. I appreciate that some commenters don’t necessarily agree with him and they are more than welcome to continue to make their counter-arguments. But this is his book we are reviewing, so I must continue to express his viewpoint. I think there are rich treasures to mine in making analogies between the natural world and the supernatural world. How can we even begin to understand the Kingdom of God, God’s realm, without analogy to our common sense experience? Most of the Kingdom parables of Jesus used mundane natural world examples to explain the nature of the Kingdom. Trees bearing fruit, wise and foolish builders, sower sowing seed, seed sown on different ground, mustard seeds, lamp on a stand and not under a bushel, and so. So what’s wrong with wave/particle duality and divine/human duality as an analogy?
I’m not as well read in the Fathers as some, but, there was development of expression and means of stating the truths that were passed down from the apostles. The meaning of “I and the Father are one” vs. “the Father is greater than I” was not obvious to Arius and his followers. At least the expression of what was meant had to be expanded upon. But, as I said, that’s Polkinghorne’s viewpoint, so I going to do my best to represent it as faithfully as I can. I certainly don’t agree with everything Polkinghorne says, as I noted before for example, he tends toward open theism, but it should make for some thought-provoking discussion.
So John believes that similarities will emerge in the ways in which experience impacts upon thinking and the manner in which heuristic strategies, that is an approach to problem solving, learning, or discovery that employs a practical method not guaranteed to be optimal or perfect, but sufficient for the immediate goals, are developed to yield fuller comprehension. He says four exemplary comparisons illustrate the point. These four comparisons are:
- Techniques of discovery: Experience and understanding.
- Defining the problem: Critical questions.
- Expanding horizons: New regimes.
- Critical events of particular significance.
(1) Techniques of discovery: Experience and understanding. Advance in understanding requires a subtle and creative interaction between experience and conceptual analysis.
(a) Theoretical creativity and experimental constraint. In Chapter 1, he stressed the indispensable role played by experiment in driving the development of quantum physics. He now wants to redress the balance a little in favor of the theorists by emphasizing the creative role of conceptual exploration. An outstanding example of the creativity Polkinghorne is talking about was Einstein’s ability to write down in November 1915 the equations of general relativity, fully formed after years of brooding on the nature of gravity.
In 1905, Albert Einstein determined that the laws of physics are the same for all non-accelerating observers, and that the speed of light in a vacuum was independent of the motion of all observers. This was the theory of special relativity. It introduced a new framework for all of physics and proposed new concepts of space and time. Einstein then spent 10 years trying to include acceleration in the theory and published his theory of general relativity in 1915. In it, he determined that massive objects cause a distortion in space-time, which is felt as gravity.
Two objects exert a force of attraction on one another known as “gravity.” Sir Isaac Newton quantified the gravity between two objects when he formulated his three laws of motion. The force tugging between two bodies depends on how massive each one is and how far apart the two lie. Even as the center of the Earth is pulling you toward it (keeping you firmly lodged on the ground), your center of mass is pulling back at the Earth. But the more massive body barely feels the tug from you, while with your much smaller mass you find yourself firmly rooted thanks to that same force. Yet Newton’s laws assume that gravity is an innate force of an object that can act over a distance.
As noted above, in his theory of special relativity, he determined that the laws of physics are the same for all non-accelerating observers, and he showed that the speed of light within a vacuum is the same no matter the speed at which an observer travels. As a result, he found that space and time were interwoven into a single continuum known as space-time. Events that occur at the same time for one observer could occur at different times for another.
As he worked out the equations for his general theory of relativity, Einstein realized that massive objects caused a distortion in space-time. Imagine setting a large body in the center of a trampoline. The body would press down into the fabric, causing it to dimple. A marble rolled around the edge would spiral inward toward the body, pulled in much the same way that the gravity of a planet pulls at rocks in space.
The orbit of Mercury is shifting very gradually over time, due to the curvature of space-time around the massive sun. Einstein said the happiest day of his life was when he found that his new theory of gravity perfectly fitted the behavior of the planet Mercury, whose motion had long been known to exhibit a small discrepancy with the predictions of Newtonian theory. John says:
The interplay between theory and experiment in physics is deeper than simple dialogue about the interpretation of experimental results. It involves a creative interaction of a profoundly truth-seeking kind between stubborn experimental findings and imaginative theoretical exploration. Truly illuminating discovery far exceeds in subtlety and satisfaction the plodding Baconian accumulation and sifting of a host of particulars, in the hope of stumbling on some useful generalization.
(b) Christology from below and from above. Polkinghorne believes that scientific progress through a dialectical engagement between experimental challenge and theoretical conceptual exploration has its analogue in theology. An important component in Christological thinking is a careful evaluation of what can learnt historically about the life of Jesus of Nazareth and about the experiences of the early Church.
These first century events are the experiential counterparts for theology of the experiments that initiated the development of quantum physics—what theologians call “Christology from below”, since the movement of thought is upwards from events to understanding. Just as physics has to combine experimental challenge with conceptual exploration, so theology has also to complement Christological argument from below with further argument “from above”. For theology, the tools for this investigation would be provided from resources of philosophy, in contrast to physics recourse to the equations of mathematics. That is why it is often asserted that Christianity “baptized” Greek philosophy. Not that the church Fathers accepted it wholly, but used some of the ideas and re-defined them according to Christian understanding in order to articulate “what had already been believed from the beginning” i.e. what had percolated “up from below” in the early Churches experiences and teaching of the apostles.
(2) Defining the problem: Critical questions. A sharp and selective focus on issues of critical significance is essential to achieve progress in understanding.
(a) Quark theory. The discovery of the Standard Model of quark theory proceeded through the successive identification of two key issues that had to be settled. The first arose from the search for an underlying order hoped to be present in the welter of new elementary particles that were discovered by experiment from the 1950s onward.
Before the Second World War, Heisenberg had suggested that, since protons and neutrons behave in very similar ways inside the nucleus, despite their having quite different electrical properties that might be bracketed together for some purposes and treated as two states of a generic entity he called a “nucleon”. The numerous post-war discoveries of new states of nuclear matter encouraged a greatly enhanced boldness in thinking along these lines. A helpful summary of the timeline of the development of the Standard Model of quark theory is given here.
A fascinating and suggestive answer had been found to the question of how to introduce some taxonomic order in the particle zoo, but this led to the second question of whether this was just a useful mathematical trick, not really much more than an intriguing mnemonic, or whether it was the sign of the presence of an actual underlying physical structure of a quark-like kind.
Enter the invention of particle accelerators where the investigation of behavior in an extreme physical regime where high-energy projectiles bounced off target particles at wide angles. This kind of encounter probed the inner structure of the target in a transparent way. Extremity of circumstance had produced simplicity of analysis.
The study of deep inelastic scattering, as these kinds of experiments are called, revealed phenomena that correspond exactly to the projectiles having struck quarks within the target. In the judgment of physicists, the reality of quarks had been convincingly established, despite the fact that no single quark has ever been seen in isolation in the laboratory.
(b) Humanity and divinity. Polkinghorne thinks there are three critical questions that theologians must ask to find an acceptable interpretation of the Church’s knowledge and experience of Jesus Christ and its consequent understanding of the nature of God.
- Was Jesus indeed resurrected on the third day, and if so, why was Jesus alone among all humanity, raised from the dead within history to live an everlasting life of glory beyond history?
- Why did the first Christians feel driven to use divine-sounding language about the man Jesus?
- What was the basis for the assurance felt by the first disciples that through the risen Christ they had been given a power that was transforming their lives in a new and unprecedented way?
He notes that some people see Jesus as differing only in degree from the rest of humanity. Jesus’ role is seen as that of providing an example of what humanity might aspire to in relationship with God. According to this view, while Jesus was unique in his time, such a level of life with God might be attainable also by others who come later. He doesn’t see this position as offering satisfactory answers to the 3 critical questions of Christology. If Jesus was just an unusually inspired man, use of the divine language of lordship about him would seem to have been an unfortunate error, quite inappropriate to someone who was simply a human being, however remarkable. Especially considering those first Christians were Jews. John says:
What theologians call the work of Christ—the forgiveness of sins, victory over death, and the bestowal of the Spirit—is an important clue to the nature of Christ. I believe that only an understanding of Jesus that sees in him not only full humanity, but also the fullness of the divine life itself, offers a prospect of meeting adequately the demands made by the New Testament witness to him.