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Although spacetimes correspond to Lorentzian metrics, one can often analytically continue these to complete Riemannian metrics. Indeed, the first example of an inhomogeneous Einstein metric on a compact manifold was found by Page, by taking a certain limit of the Kerr–de Sitter metrics [185Jump To The Next Citation Point], giving a metric on --- ℂ ℙ2#ℂ ℙ2.