In August 1984, M. Green and J. Schwarz ushered in the latest revolution in particle physics with their discovery of mathematically consistent superstring theories. Since then, there has been a vast effort to understand string theory and to bring it to bear on the major unsolved problems of particle physics. Some have hailed it as the final unified theory of everything, while others have damned it as recreational mathematics, theology, or something worse. What is the theory that has caused this controversy and what is at the root of the turmoil?

The basic idea of string theory is to replace elementary particles such as photons, electrons, quarks, and gravitons with open or closed loops of string. These strings are supposed to be the fundamental stuff of which all matter and all forces are made. They can carry charges, either stuck on the ends of open strings, or flowing as currents...

Interested in reading more?

Become a Member of

Receive full access to digital editions of The Scientist, as well as TS Digest, feature stories, more than 35 years of archives, and much more!