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arXiv · 0801.2808

The circular loop equation of a cosmic string with time-varying tension

Hongbo Cheng·Yunqi Liu
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Abstract

The equation of circular loops of cosmic string with time-dependent tension is studied in the Minkowski spacetime and Robertson-Walker universe. We find that, in the case where the tension depends on some power of the cosmic time, cosmic string loops with time-varying tension should not collapse to form a black hole if the power is lower than a critical value.

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Hongbo Cheng, Yunqi Liu. 2008-01-18. The circular loop equation of a cosmic string with time-varying tension. https://doi.org/10.1142/s0217732308026340

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