Although string theory is a young science, it has had many notable achievements. What follows are some landmark events in the history of string theory:
1968: Gabriele Veneziano originally proposes the dual resonance model.
1970: String theory is created when physicists interpret Veneziano’s model as describing a universe of vibrating strings.
1971: Supersymmetry is incorporated, creating superstring theory.
1974: String theories are shown to require extra dimensions. An object similar to the graviton is found in superstring theories.
1984: The first superstring revolution begins when it’s shown that anomalies are absent in superstring theory.
1985: Heterotic string theory is developed. Calabi-Yau manifolds are shown to compactify the extra dimensions.
1995: Edward Witten proposes M-theory as unification of superstring theories, starting the second superstring revolution. Joe Polchinski shows branes are necessarily included in string theory.
1996: String theory is used to analyze black hole thermodynamics, matching earlier predictions from other methods.