Selfdual spaces with complex structures, Einstein-Weyl geometry and geodesics

David M. J. Calderbank; H. Pedersen

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arXiv · math/9911117

Selfdual spaces with complex structures, Einstein-Weyl geometry and geodesics

David M. J. Calderbank·H. Pedersen

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Abstract

We study the Jones and Tod correspondence between selfdual conformal 4-manifolds with a conformal vector field and abelian monopoles on Einstein-Weyl 3-manifolds, and prove that invariant complex structures correspond to shear-free geodesic congruences. Such congruences exist in abundance and so provide a tool for constructing interesting selfdual geometries with symmetry, unifying the theories of scalar-flat Kahler metrics and hypercomplex structures with symmetry. We also show that in the presence of such a congruence, the Einstein-Weyl equation is equivalent to a pair of coupled monopole equations, and we solve these equations in a special case. The new Einstein-Weyl spaces, which we call Einstein-Weyl ``with a geodesic symmetry'', give rise to hypercomplex structures with two commuting triholomorphic vector fields.

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BibTeX RIS

David M. J. Calderbank, H. Pedersen. 1999-11-16. Selfdual spaces with complex structures, Einstein-Weyl geometry and geodesics. https://arxiv.org/abs/math/9911117

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