Gravitational wave landscape of cosmic string networks with varying tension
Abstract
We fully classify the phenomenology of gravitational wave emission from scaling cosmic string networks with varying tension and compute the spectral indices of the resulting stochastic backgrounds. In string compactifications, periods of varying tension occur when moduli acquire a time dependence. We present concrete examples in type IIB string theory as D3- and NS5-branes wrapping internal cycles, which become dynamical due to the effect of moduli potentials. Moreover, we use swampland constraints to derive general bounds on the allowed time variation of the effective string tension in Friedmann-Lemaitre-Robertson-Walker backgrounds and on the resulting spectral indices.
Fields of Study & Subjects
Cosmology and Gravitation Theories
Black Holes and Theoretical Physics
Galaxies: Formation
Evolution
Phenomena
Publication details
- Journal / source
- Physical review. D/Physical review. D.
- Publisher
- American Physical Society (APS)
- Volume
- 114
- Issue
- 4
- Publication date
- 13 August 2026
- Language
- EN