Oral comunication
D. Grüber
Abstract
Domain wall networks can arise as a consequence of spontaneous symmetry breaking in the early universe. These networks
are then expected to source a stochastic gravitational wave background throughout their lifetime. We have computed the
corresponding power spectrum for frictionless domain walls assuming a radiation + $Lambda$CDM background and that
a constant fraction of the energy lost by the network goes into gravitational radiation. Additionally, we developed a
semi-analytical model to predict the spectral distribution of the SGWB in terms of two free parameters. In this talk I will
introduce this framework and its parameters, describing the numerically obtained power spectra as well as accurate
analytical approximations which rely on the assumption of a perfect scaling regime in the radiation and matter eras. I will
also confront our model with cosmic microwave background constraints and with the recent detection of the stochastic
gravitational wave background by pulsar timing arrays.
18th Iberian Cosmology Meeting (IberiCOS2024)
Salamanca, Spain
2024 March
