The Beauty of Physics

As your General Physics final approaches, beauty is probably the last thing on your mind. Your notebooks are overflowing with scribbled equations, integrals are pouring out your ears, and you stopped showering days ago—a fact of which your suitemates are all too aware. As difficult as it may be to believe, however, beauty was a driving force behind many of the equations you are struggling to memorize.

Paul Dirac, one of the founders of quantum mechanics, famously said, “A physical theory must possess mathematical beauty.” In the most basic explanation, mathematical beauty is related to simplicity and surprise. The importance of simplicity goes back centuries and is most famously supported by Occam’s razor, the principle that states the simplest solution to a problem is best.

Occam’s razor may seem like a cop-out, but historically it has often supported ideas that turned out to be right. In the 16th century, the leading idea about the motion of the stars and planets was Ptolemy’s epicycles, which posited that all heavenly bodies orbited the earth but also moved in small circles on their own, as if each were a moon circling an invisible planet. As astronomical observations grew increasingly accurate, the Ptolemaic system was forced to become almost impossibly complex to accommodate the new information. One of the first clues that Copernicus was onto something with his idea of a heliocentric universe was that his model was simpler. Once Kepler refined the initial theory with the idea of elliptical orbits, the math describing the motion of planets and stars fell into place—beautifully.

Over 100 years later, Newton’s theory of gravity impressed and convinced the scientific community with the way its math framed and explained centuries of observations, even though there was no way to experimentally test gravity in relation to stars and planets. Even more groundbreaking than the simplicity of providing one set of equations to describe both earthly and heavenly motion was the surprise that just one set of equations could be applied to both those realms. Einstein’s theory of general relativity also capitalizes on beauty, starting from the simple and surprising premise that all frames of reference are equal and moving toward a logically impeccable equation that describes the relationship between mass and space-time.

More recently, string theory has taken the lead among the most beautiful theories, with its premise that fundamental particles are tiny, vibrating stings instead of the tiny marbles we have always imagined. From there, it seamlessly unites quantum mechanics (the physics of the very small) and relativity (the physics of the very big)—that is, if you allow for the assumption that the universe has 10 spatial dimensions instead of just the three we observe. String theory has a lot of problems—chief among them that it cannot currently be experimentally tested—but a lack of elegance is not one of them. It has enchanted physicists and non-scientists (including me) for decades, holding out the promise not only of the theory of everything, but of many surprise twists along the way—including the possibility of multiple universes and the aforementioned extra dimensions.

The current impossibility of experimentally testing string theory keeps us from determining whether it is an accurate way of describing our reality, but it does not exclude it from being interesting or relevant. Not only is it beautiful in and of itself, but it has also led to new ways of thinking about seemingly unrelated problems. Scientists at the Relativistic Heavy Ion Collider (RHIC) are able to apply some string theory equations to their models of the quark-gluon plasma that made up the early universe, and when they produce that substance in collisions at RHIC, it has an extremely high temperature. A possible mathematical explanation for that temperature comes from a string theory model of black holes. “This is not the real world, this is a mathematical description by which you can gain insight into the real world of real RHIC collisions,” Columbia physics professor and RHIC scientist William Zajc explains. But for him, even the theoretical connection between the branches of physics is intriguing because it gives scientists an unexpected way to think about old problems.

There is beauty in learning how to look at the world in a different way, which is what we are told will happen to us in college. Unlike some of the seniors graduating in a few weeks, I did not have a political awakening, undergo a religious conversion, or reinvent myself at Barnard—but I did see a cosmic ray in a cloud chamber. Soon enough, I also started “seeing” particles and waves in every beam of light, the quarks that make up all normal matter, and even dark matter and dark energy. Once I learned about them, there was no going back.

Many people have thought about the relationship between physics and poetry, including Dirac, who said, “In science one tries to tell people, in such a way as to be understood by everyone, something that no one ever knew before. But in poetry, it’s the exact opposite.” Studying both science and literature has allowed me to see the ways in which both disciplines are connected. I see the uncertainty principle in translation and postmodernism in string theory. I see collisions—of cultures, of languages, of particles—as the most interesting moments to study. I see poetry in physics, physics in poetry, and beauty in both.

Elizabeth Wade is a Barnard senior majoring in comparative literature. Fear of Physics runs alternate Mondays.