The belief that all physical matter is made up of vibrating "strings." For example, protons, electrons and neutrons are strings each with different vibrations. Officially known as "superstring theory, ...

For decades, physicists have been trying to combine quantum physics and general relativity into a single, unified theory. One of the leading contenders is string theory, an elegant vision in which ...

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute, host of Ask a Spaceman and Space Radio, and author of "Your Place in the Universe." Sutter contributed this article ...

String theory aims to explain all fundamental forces and particles in the universe—essentially, how the world operates on the smallest scales. Though it has not yet been experimentally verified, work ...