LETTER Causality Violating Geodesics in Bonnor’s Rotating Dust Metric
نویسندگان
چکیده
Causality violating paths are known to exist in many spacetimes satisfying the Einstein field equations, especially those solutions associated with rotating matter or rotating singularities [1–3] (see also Bonnor [4], and references in [5]). However, examples of causality violating geodesics are sparse in the scientific literature. Chandrasekhar and Wright [6] showed that the Gödel spacetime [1] admits no closed timelike geodesics, even though the spacetime includes closed timelike curves. In the case of the Kerr metric, Carter [3] proved that closed timelike paths exist for some parameter values of the metric. Calvani et al. [7] then showed that a class of timelike geodesics in the Kerr spacetime do not violate causality, but de Felice and Calvani [8] later found numerical solutions for null geodesics that
منابع مشابه
Causality Violating Geodesics in Bonnor’s Rotat- ing Dust Metric
We exhibit timelike geodesic paths for a metric, introduced by Bonnor [11] and considered also by Steadman [13], and show that coordinate time runs backward along a portion of these geodesics.
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