For millennia, thinkers and dreamers have been seeking the key that finally unlocks the secrets of the universe. In the last few decades, scientists have come to believe they have found it, dangling from something called string theory.

Particle physicists can explain the subatomic composition of the universe with quarks, muons, and other basic building blocks, as well as the fundamental forces in the universe: gravity, electromagnetism, and the weak and strong nuclear forces. But when it comes down to explaining the behavior of gravity on a microscopic level, the standard approaches fall short. In the last few decades, string theory has provided a way to describe these particles and forces, and to unify them. As it attempts to provide a more complete description of the structure of our universe, string theory has earned a nickname: the theory of everything.

Steven Gubser, a professor of physics at Princeton University has stripped string theory down to the essentials for a more digestible and non-technical explanation. Through the use of physics demonstrations, Gubser explains how string theory relates to motion, energy, and electromagnetism, as well as how quantum mechanics meshes with the theory of strings, and how string theory relates to the real world. He is known as one of the creators of the gauge-string duality, and his research has helped connect string theory to heavy-ion experiments.

Gubser’s book The Little Book of String Theory (Princeton University Press) is available for sale and signing.