The History of String Theory Part 2

In the early 1970s physicists were discouraged when many of their experiments with string theory showed that its predictions were at odds with experimental data. String vibrations produce observable properties that can be seen in fundamental particles, but there were other vibration patterns that seemed to have little bearing in reality. These extra vibrations were soon discovered to correspond exactly with gravitons. Gravitons are particles that have not yet been found experimentally, but can be predicted by physicist. The discovery was not well received by the scientific community and string theory was abandoned by all but a few physicists.

In 1984, after over a dozen years of research and much belittling by their colleagues, Michael Green and John Schwarz produced a paper that resolved the conflicts between string theory and quantum mechanics. The paper also showed that string theory could encompass the four fundamental forces and matter. This period became known as the first superstring revolution. Physicist all around the word joined the research on the theory that they had rejected in previous years.

1984-86 saw thousands of papers published on string theory. These papers showed that the features of the standard model could be logically and naturally derived from the new string theory. A major drawback was that the equations where so difficult that their exact form could not be determined and approximations had to be used to replace their complex forms. Physicist became frustrated with these complex equations and once again abandoned string theory for other projects.

At a conference at the University of Southern California in 1995 Edward Witten announced a comprehensive plan to move past the approximations used during the first superstring revolution. Witten’s plan has sparked the second superstring revolution and will have physicist exploring ever deeper into the complexities of string theory.