An analytic method in general relativity (Q1586718)

An analytic method, called the `Bochner technique', has been used for fifty years to describe global Riemannian and Kähler geometries. The author uses this method to describe conformally Killing vector fields and harmonic timelike vector fields on a Lorentzian manifold and to study hydrodynamic models of the Universe, the existence of closed spacelike sections, and the possibility of fibering Lorentzian manifolds.