| We are investigating the breakdown of the equivalence between two types of cosmic strings that can be produced in models with N=2 supersymmetric quantum electrodynamics, the so-called D-term strings and F-term strings. These are equivalent in flat space, as they are obtained from each other by a rotation of the two supersymmetries. But in supergravity the equivalence is broken, only one local supersymmetry survives and the rotation is no longer possible. We are investigating the nature of the breakdown from the point of view of N=2 supergravity. |
