Conveners
Gravitational Waves
- Edoardo Vitagliano (University of Padua & INFN Padua)
Axion inflation is an extension of the slow-roll paradigm featuring helical gauge-field production with possible consequences for inflationary magnetogenesis, leptogenesis, reheating, and gravitational wave production. I focus on the latter, studying the detectability of gauge-field-induced gravitational waves from axion inflation. For this, I consider two models: the first featuring a...
Strong first-order phase transitions offer a compelling explanation for the stochastic gravitational wave background in the nano-Hertz range measured by pulsar timing arrays (PTA). In this talk, I will consider a classically conformal dark sector in which the breaking of a dark U(1) gauge symmetry gives rise to a gravitational wave background that can fit the PTA data and additionally sources...
Birefringence effects associated with the evolution of the polarization of light have been proposed as a way to detect axion DM. We exploit this method for gravitational wave detection, pointing out how we can describe axions and GW with a unified treatment. We show that by exploiting this method, the optical cavities used by the ALPSII experiment can probe in the near future GWs with...
A novel mechanism to produce a cosmic network of fundamental superstrings based on a time-varying string tension has been recently proposed. It has been found that fundamental (super)strings can grow in a kinating background driven by the volume modulus of Type IIB string compactifications. In this talk, based on [arXiv:2503.11293][1], I will generalise this analysis using dynamical systems...
The Chern-Simons coupling between an axion-like field and a U(1) gauge field is a well-known mechanism for generating chiral gravitational waves (GWs) during inflation. However, its observational signature, e.g., in the Cosmic Microwave Background (CMB), is challenged by stringent constraints on primordial curvature perturbations, which are also sourced by this interaction.
We explore a...
