The Fall and Rise of String Theory
The upcoming Evolved Laser Interferometer Space Antenna could help verify string theory's predictions of gravity waves. Three spacecraft will orbit around the sun and measure tiny ripples in space-time via sensitive lasers [credit: AEI/MM/EXOZET]. Inset: A 2D slice of the 6D Calabi-Yau quintic manifold. Andrew J. Hanson, Indiana University. [CC BY-SA 3.0 or Attribution], via Wikimedia Commons.
String theory was once the hottest thing in physics. In the 1980s and ’90s, it promised seemingly unlimited bounty. Arising from the notion that matter and energy are fundamentally composed of tiny, vibrating strings rather than pointlike particles, this theory attempted to unify all the known forces into a single, elegant package. Some physicists hailed string theory as the long-sought “theory of everything.”
Harvard University physicist Andrew Strominger, a leader in string theory for decades, remembers the early enthusiasm. "At the time of its new popularity," he says, "there was a declaration that we had solved all the problems in physics and had the final theory in hand..."