## $${\mathcal H}$$-space with a cosmological constant.(English)Zbl 0549.53042

Summary: It is demonstrated that a real-analytic 3-manifold with Riemannian conformal metric is naturally the conformal infinity of a germ-unique real-analytic 4-manifold with real-analytic Riemannian metric satisfying the self-dual Einstein equations with cosmological constant -1. Moreover, this result holds if ’Riemannian’ is replaced in the first case by ’Lorentzian’ (i.e. signature $$+--)$$ and in the second case by ’pseudo- Riemannian with signature $$++--'$$, or if ’real-analytic’ is replaced by ’complex-analytic’ and ’Riemannian’ is replaced by ’holomorphic’. This provides a cosmological-constant analogue of Newman’s $${\mathcal H}$$-space construction.

### MSC:

 53C20 Global Riemannian geometry, including pinching 53C50 Global differential geometry of Lorentz manifolds, manifolds with indefinite metrics 53C80 Applications of global differential geometry to the sciences
Full Text: