TY - EJOUR AU - Buchmuller, Wilfried AU - Domcke, Valerie AU - Schmitz, Kai TI - Metastable cosmic strings IS - CERN-TH-2023-118 M1 - PUBDB-2023-04515 M1 - CERN-TH-2023-118 M1 - DESY-23-117 M1 - arXiv:2307.04691 M1 - MS-TP-23-37 PY - 2023 N1 - 28 pages, 3 figures published in JCAP AB - Many symmetry breaking patterns in grand unified theories (GUTs) give rise to cosmic strings that eventually decay when pairs of GUT monopoles spontaneously nucleate along the string cores. These strings are known as metastable cosmic strings and have intriguing implications for particle physics and cosmology. In this article, we discuss the current status of metastable cosmic strings, with a focus on possible GUT embeddings and connections to inflation, neutrinos, and gravitational waves (GWs). The GW signal emitted by a network of metastable cosmic strings in the early universe differs, in particular, from the signal emitted by topologically stable strings by a suppression at low frequencies. Therefore, if the underlying symmetry breaking scale is close to the GUT scale, the resulting GW spectrum can be accessible at current ground-based interferometers as well as at future space-based interferometers, such as LISA, and at the same time account for the signal in the most recent pulsar timing data sets. Metastable cosmic strings thus nourish the hope that future GW observations might shed light on fundamental physics close to the GUT scale. KW - scale: grand unified theory (INSPIRE) KW - symmetry breaking: scale (INSPIRE) KW - frequency: low (INSPIRE) KW - cosmic string (INSPIRE) KW - string (INSPIRE) KW - interferometer (INSPIRE) KW - network (INSPIRE) KW - gravitational radiation (INSPIRE) KW - stability (INSPIRE) KW - inflation: model (INSPIRE) KW - embedding (INSPIRE) KW - pulsar (INSPIRE) KW - suppression (INSPIRE) KW - LISA (INSPIRE) KW - monopole (INSPIRE) KW - cosmological model: parameter space (INSPIRE) LB - PUB:(DE-HGF)25 DO - DOI:10.3204/PUBDB-2023-04515 UR - https://bib-pubdb1.desy.de/record/587797 ER -