Chapter 6. Lectures on Topological String Theory

In string theory, one typically studies em beddings of the string worldsheet E (which is a Riemann surface) into a 10-dimensional manifold of the form X : Σ → R^(1,3) × M, with M a compact 6-dimensional manifold. In the following, we will restrict our attention to the study of supersymmetric sigma models onto the 6 compact dimensions. In particular, we will assume M to be a Calabi-Yau threefold so that the theory possesses N = (2, 2) worldsheet superconformal symmetry.