During the summers between high school and college, proud science geek that I was, I split my time between playing beach volleyball and reading Feynman Lectures in Physics, a classic college physics textbook. Right at the beginning of Richard Feynman’s phenomenal text, in Volume 1, Lecture 2, I found a quote that I never forgot. (I will carefully adapt it here from chess to soccer, in keeping with the spirit of the upcoming World Cup.)
“What do we mean by ‘understanding’ something?” We can imagine that this complex set of moving things that makes up the “world” is something like a large [soccer] a game played by the gods, and we are observers of the game. We don’t know what the rules of the game are; all we are allowed to do is watch the playing. Of course, if we watch long enough, we might eventually guess some of the rules. The rules of the game are what we mean by fundamental physics. Even if we know every rule, however, we may not be able to understand why a certain move is made in the game simply because it is too complicated and our minds are limited. If you play [soccer] you should know that it is easy to learn all the rules, yet it is often very difficult to choose the best move or understand why the player moves the way he does. It’s like that in nature, only much more so.”
In this analogy, the laws of nature are similar to the rules of a game. The role of physics is to find out what those rules are. By the time I read the above passage, I already knew that I wanted to spend my life trying to understand the game of nature, but Feynman’s book helped turn my youthful interest into an abiding passion.
Scientists try to figure things out by methodically observing what happens in the world, using our tools and our intuition in tandem with our deductive abilities. This method provided the trajectory for the pursuit of scientific knowledge, so that what began with the pre-Socratic philosophers in ancient Greece around 650 BC became what we call modern science more than two millennia later , with the work of Galileo, Kepler, Descartes, Newton, and many others.
Changes in Space
Feynman’s analogy illustrates several aspects of scientific thinking, the most obvious being our eternal blindness. Even when we decode some of the rules of the game, our understanding remains incomplete. As the French philosopher Bernard Le Beauvier de Fontenelle wrote in 1686, “All philosophy is the product of two things: curiosity and short-sightedness.” There is a creative tension between wanting to see everything and simply not being able to.
To illustrate this, we can think historically. The cosmos looked much different to Columbus in 1492 than it did to Newton in the late 17th century. In turn, Newton’s Cosmos was very different from ours. In the early 1500s, the universe was bounded, enclosed as a sphere, with the Earth fixed at the dead center of creation. For Newton, the Cosmos is infinite, its mechanisms are described by precise quantitative laws, as if nature knew mathematics. To discover the laws of nature was to read the mind of God, the Great Geometer, and thus finally to understand the rules of the game. And how do we do that? By observing what nature does – essentially, observing the game as it is played. Today we do not know whether the universe is infinite or not. But we know it’s expanding—the distances and velocities between galaxies are growing at an accelerated rate.
The laws of nature are how we organize the patterns and behaviors we can observe. Some patterns are easy to identify, such as the tides, the seasons, or the phases of the moon, and Newtonian physics explains it all well. Others are harder to figure out, such as the energy spectrum of the hydrogen atom, the motion of Mercury’s orbit, or superconductivity. If we continue with Feynman’s analogy, the gods play a very subtle game of football, mixing visible moves with others that we cannot see. We see volcanic eruptions on Earth, but not on Saturn’s moon Enceladus. We see waves breaking on the beach, but not electron waves diffracted by crystals. To reveal at least some of the unseen rules, we expand our vision with special tools. Our reality enhancers include telescopes, microscopes, mass spectrometers, particle accelerators – sensors and detectors of all kinds. Without these tools of inquiry, modern science is blind.
New tools have the potential to reveal new and often unexpected laws. Sometimes what they discover is revolutionary and forces us to rethink some fundamental aspects of reality: the structure of space and time, the relationship between matter and energy, the properties of a star, the origin of the universe or of life. Science is the sum total of our efforts to understand things. It is a continuous, self-correcting process and is always incomplete. The more we learn about the ins and outs of this celestial football game, the more we realize we have yet to learn. Who knows, maybe the laws form an endless labyrinth, without beginning and end. Perhaps the best we can do is glimpse it here and there, much to the amusement of the watching gods.