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arXiv · 1203.6827

Super Weyl invariance: BPS equations from heterotic worldsheets

Stefan Groot Nibbelink·Leonhard Horstmeyer
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Abstract

It is well-known that the beta functions on a string worldsheet correspond to the target space equations of motion, e.g. the Einstein equations. We show that the BPS equations, i.e. the conditions of vanishing supersymmetry variations of the space-time fermions, can be directly derived from the worldsheet. To this end we consider the RNS-formulation of the heterotic string with (2,0) supersymmetry, which describes a complex torsion target space that supports a holomorphic vector bundle. After a detailed account of its quantization and renormalization, we establish that the cancellation of the Weyl anomaly combined with (2,0) finiteness implies the heterotic BPS conditions: At the one loop level the geometry is required to be conformally balanced and the gauge background has to satisfy the Hermitean Yang-Mills equations.

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Stefan Groot Nibbelink, Leonhard Horstmeyer. 2012-06-22. Super Weyl invariance: BPS equations from heterotic worldsheets. https://doi.org/10.1007/jhep07(2012)054

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