Type IIA string

In theoretical physics, type IIA string theory is one of five consistent supersymmetric string theories in ten dimensions. It is based on oriented closed strings.

At low energies, type IIA string theory is described by type IIA supergravity in ten dimensions which is a non-chiral (left-right symmetric) theory with (1,1) d=10 supersymmetry; the fact that the anomalies in this theory cancel is therefore trivial.

In the late 1980s, if was realized that type IIA string theory is related to type IIB string theory by T-duality.

In the 1990s it was realized by Edward Witten (building on previous insights by Michael Duff, Paul Townsend, and others) that the limit of type IIA string theory in which the string coupling goes to infinity becomes a new 11-dimensional theory called M-theory.