Calabi–Yau compactification of heterotic superstrings
In Chapter 5 we showed that toroidal compactifications of superstrings can lead at low energies to 4d theories, albeit with too much supersymmetry to allow for chirality, an essential ingredient of particle physics. We will thus be interested in constructing more general classes of compactifications leading to chiral theories in 4d, an enterprise starting in this chapter and reaching until Chapter 12, and for which it is convenient to give an aerial view.
7.1 A road map for string compactifications
There are different options to achieve the construction of chiral 4d compactifications in string theory, summarized in Figure 7.1, and roughly classified according to the underlying 10d or 11d ...