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تسجيل مستخدم جديدHas NANOGrav found first evidence for cosmic strings?
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The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has recently reported strong evidence for a stochastic common-spectrum process affecting the pulsar timing residuals in its 12.5-year data set. We demonstrate that this process admits an interpretation in terms of a stochastic gravitational-wave background emitted by a cosmic-string network in the early Universe. We study stable Nambu-Goto strings in dependence of their tension $Gmu$ and loop size $alpha$ and show that the entire viable parameter space will be probed by an array of future experiments.
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