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arXiv · 1610.02343

Pure Connection Formulation, Twistors and the Chase for a Twistor Action for General Relativity

Yannick Herfray
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Abstract

This paper establishes the relation between traditional results from (euclidean) twistor theory and chiral formulations of General Relativity (GR), especially the pure connection formulation. Starting from a $SU(2)$-connection only we show how to construct natural complex data on twistor space, mainly an almost Hermitian structure and a connection on some complex line bundle. Only when this almost Hermitian structure is integrable is the connection related to an anti-self-dual-Einstein metric and makes contact with the usual results. This leads to a new proof of the non-linear-graviton theorem. Finally we discuss what new strategies this "connection approach" to twistors suggests for constructing a twistor action for gravity. In appendix we also review all known chiral Lagrangians for GR.

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Yannick Herfray. 2018-01-09. Pure Connection Formulation, Twistors and the Chase for a Twistor Action for General Relativity. https://doi.org/10.1063/1.5012268

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