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arXiv · hep-th/0407193

F-term strings in the Bogomol'nyi limit are also BPS states

A. Achucarro·J. Urrestilla
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Abstract

We derive the Bogomol'nyi equations for supersymmetric Abelian F-term cosmic strings in four-dimensional flat space and show that, contrary to recent statements in the literature, they are BPS states in the Bogomol'nyi limit, but the partial breaking of supersymmetry is from N=2. The second supersymmetry is not obvious in the N=1 formalism, so we give it explicitly in components and in terms of a different set of N=1 chiral superfields. We also discuss the appearance of a second supersymmetry in D-term models, and the relation to N=2 F-term models. The analysis sheds light on an apparent paradox raised by the recent observation that D-term strings remain BPS when coupled to N=1 supergravity, whereas F-term strings break the supersymmetry completely, even in the Bogomol'nyi limit. Finally, we comment on their semilocal extensions and their relevance to cosmology.

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A. Achucarro, J. Urrestilla. 2004-09-30. F-term strings in the Bogomol'nyi limit are also BPS states. https://doi.org/10.1088/1126-6708%2F2004%2F08%2F050

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