The following is an except from Quantum Leap: How John Polkinghorne Found God in Science and Religion, a portrait of influential physicist and Anglican priest John Polkinghorne. In this series, we have learned a bit about Polkinghorne’s transition from the world of physics to the priesthood, and the responses it drew from fellow scientists, especially from fellow colleague and outspoken atheist Stephen Weinberg. Today we look at Polkinghorne's scientific achievements and why he chose to leave that career behind.
In his professional research, Polkinghorne was part of the team that began to challenge the longstanding conclusion that the smallest known particles that made up atoms were protons and neutrons. Experimental evidence suggested that there was something “inside” protons and neutrons. But what could that be? It became clear that those particles were made up of other particles, but no one could see what those smaller particles were. The physicists knew that the particles were “there” but they moved too quickly to be independently observed. Still, because of their experiments the researchers were motivated to believe that the particles inside the protons and neutrons were real. Eventually they were labeled quarks and gluons.
In high-powered accelerators, underlying patterns of activity could be inferred from the observation of collisions. Particles would be smashed into each other at great speed and the resulting “debris” analyzed to see what was going on. The process was very complex and might be compared to trying to understand how automobiles are constructed by smashing them into each other and looking at the pieces that result.
The researchers discovered that the patterns observed in the collisions in the accelerators could be described with mathematical equations. The unknown particles they were investigating had properties in common. In fact, similar components hiding inside protons and neutrons manifested themselves with suggestive regularity but the particles never appeared on their own. It would be like listening to two people talking in the dark but suspecting that it might be a ventriloquist with a dummy. How do you figure out what is going on?
The initial research was high on theory and light on observation. The mathematical arguments seemed compelling but it wasn’t clear exactly what the mathematics was describing. A question naturally arose: “Were there any actual elements, or was it all just math?” asked Murray Gell-man, who won the Nobel Prize in physics for “discovering” the quark. Gell-man, paradoxically was not sure the quarks were physically real in any simple sense, and described them as “presumably mathematical.” Perhaps they had no real existence outside of the equations describing them. Another scientist, James Bjorken, was able to show that light was bouncing off protons and neutrons in a way that suggested there were real, physical particles inside them. The flamboyant physicist and Nobel Laureate Richard Feynman extended Bjorken’s idea, adding support to the idea that quarks were more than just mathematical entities.
Polkinghorne’s research team helped make the existence of quarks mathematically precise, so that the models could be more effectively compared with the observations. “I didn’t discover the quark. My team made mathematically well-formulated models to show patterns if there were these things called quarks. The role my team played in quark understanding is that we made them mathematically respectable.”
This experience provides insight into why Polkinghorne can believe in both quarks and God, even though he has seen neither. “Physicists are quite prepared to trust in unseen realities, provided that the indirect motivations for the relevant belief are persuasive,” he said.1
After a year at Caltech, and attending a Presbyterian church nearby, Polkinghorne left the United States for a job as a lecturer at the University of Edinburgh. Two years later he was back “home,” teaching physics at Cambridge University. Even though his teaching career was just beginning, he discovered that he had a pastoral concern for his students. He experienced great satisfaction in assisting his students through successes and struggles, especially the ones he mentored in research. “Research is difficult, and that is a tricky and formative time for students,” he said. “You’re dealing with people as people, and seeing them every day. I enjoyed telling them things and helping them. The most difficult to help were those who were most confident.”
At Cambridge he headed a research group that helped to further establish what is now the widely held view of quark theory. For his contributions to developing this more complete method of seeing the world, he was inducted as a Fellow in the Royal Society.
Becoming a member of the Royal Society revealed something about Polkinghorne that surprised and disturbed him. Usually humble and self-effacing, Polkinghorne was startled by how much he obsessed over this award. “If you had to put me in some curious scheme by which my election would have been assisted by the murder of my grandmother, I would certainly have declined, but there would have been a perceptible pause for mental struggle before I did so.”2
Polkinghorne’s own soul-making took what looked like a dramatic turn when he left this distinguished physics career to become a priest. His spiritual leanings were as strong in his mid-career as they were that first day in the Holy Trinity Church when he was inspired by the story about Zacchaeus. As for physics, he felt as if he had done his bit for the subject, and that the future of his specialty was best left to younger people. Mathematical physics, like baseball, gets harder with age. He was 47.
Polkinghorne believed he had responded to his spiritual vocation by using his considerable talents for research and teaching but now it was time to step aside. “Somehow one needs mental agility more than accumulated experience, and it becomes progressively harder for an old dog to learn new tricks.”3 “I wasn’t disillusioned with physics—I just didn’t want to do it the rest of my life,” he said.
So Polkinghorne walked away from physics. Weinberg fell off his chair. Other colleagues looked on in disbelief. But Polkinghorne was more than just a physicist and he had made his mark on that ancient science. Walking away was not difficult. But he wasn’t walking away. He was walking toward a new calling, responding to his growing desire to be a minister of word and sacrament, toward a new life that he anticipated would provide “deep satisfaction.”4
Polkinghorne’s conviction that his spiritual side was rotating toward the sun came when he went on a Trinity College retreat where, except during worship, silence was the rule. Talkative and outgoing, heading off into a cloud of silence seemed like putting on a straitjacket. But he went anyway. He discovered something that many contemplative Christians had found over the centuries—that the rawness and intimacy of shared silence was spiritually rich. “I soon learned how positive is the experience of silence, and how genuinely related you become to the others who are sharing that silence with you,” he said. “One can really begin to enter into the inner space that silence opens up.”5