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تسجيل مستخدم جديدA note on the existence of standard splittings for conformally stationary spacetimes
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Let $(M,g)$ be a spacetime which admits a complete timelike conformal Killing vector field $K$. We prove that $(M,g)$ splits globally as a standard conformastationary spacetime with respect to $K$ if and only if $(M,g)$ is distinguishing (and, thus causally continuous). Causal but non-distinguishing spacetimes with complete stationary vector fields are also exhibited. For the proof, the recently solved folk problems on smoothability of time functions (moreover, the existence of a {em temporal} function) are used.
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