Heterotic flux backgrounds and their IIA duals

Understand

We study four-dimensional heterotic flux vacua with N=2 spacetime supersymmetry.

• A worldsheet perspective is used to clarify quantization conditions associated to the fluxes and the constraints these place on the moduli spaces of resulting compactifications.
• We propose that these vacua fit naturally in the context of heterotic/IIA duality as heterotic duals to compactifications on K3-fibered but not elliptically fibered Calabi-Yau three-folds.
• We present some examples of such potential dual pairs.