English

Has NANOGrav found first evidence for cosmic strings?

Cosmology and Nongalactic Astrophysics 2021-02-01 v3 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

Abstract

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 GμG\mu and loop size α\alpha and show that the entire viable parameter space will be probed by an array of future experiments.

Keywords

Cite

@article{arxiv.2009.06607,
  title  = {Has NANOGrav found first evidence for cosmic strings?},
  author = {Simone Blasi and Vedran Brdar and Kai Schmitz},
  journal= {arXiv preprint arXiv:2009.06607},
  year   = {2021}
}

Comments

7 pages, 3 figures. v2: revised treatment of the higher cosmic-string modes [see Eq. (6)], resulting in a few numerical but no qualitative changes. v3: matches version published in PRL

R2 v1 2026-06-23T18:32:01.567Z