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Cosmic String Lensing and Closed Time-like Curves

Benjamin Shlaer·S. -H. Henry Tye
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Abstract

In an analysis of the gravitational lensing by two relativistic cosmic strings, we argue that the formation of closed time-like curves proposed by Gott is unstable in the presence of particles (e.g. the cosmic microwave background radiation). Due to the attractor-like behavior of the closed time-like curve, we argue that this instability is very generic. A single graviton or photon in the vicinity, no matter how soft, is sufficient to bend the strings and prevent the formation of closed time-like curves. We also show that the gravitational lensing due to a moving cosmic string is enhanced by its motion, not suppressed.

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Benjamin Shlaer, S. -H. Henry Tye. 2005-08-31. Cosmic String Lensing and Closed Time-like Curves. https://doi.org/10.1103/physrevd.72.043532

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