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Spinning strings, cosmic dislocations and chronology protection

Vitorio A. De Lorenci·Edisom S. Moreira Jr
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Abstract

A massless scalar field is quantized in the background of a spinning string with cosmic dislocation. By increasing the spin density toward the dislocation parameter, a region containing closed timelike curves (CTCs) eventually forms around the defect. Correspondingly, the propagator tends to the ordinary cosmic string propagator, leading therefore to a mean-square field fluctuation, which remains well behaved throughout the process, unlike the vacuum expectation value of the energy-momentum tensor, which diverges due to a subtle mechanism. These results suggest that back reaction leads to the formation of a "horizon" that protects from the appearance of CTCs.

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Vitorio A. De Lorenci, Edisom S. Moreira Jr. 2004-08-21. Spinning strings, cosmic dislocations and chronology protection. https://doi.org/10.1103/physrevd.70.047502

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