Speaker
Description
Different thermal resummation techniques impact the gravitational wave (GW) spectra from cosmological first-order phase transitions predicted in a given particle physics model. To investigate this effect, we perform the first large-scale parameter scan of the electroweak phase transition (EWPT) in the dynamical real-singlet extension of the Standard Model (SM) using three different perturbative approximations of the effective potential. While predictions of the GW amplitudes from the common, 4D Daisy-resummed potentials are unreliable compared to state-of-the-art dimensionally reduced potentials, I will demonstrate that the overall detectable parameter spaces are robust up to a few percent in uncertainty. Regarding the reconstruction of the model parameters given a GW signal, I will illustrate that theoretical uncertainties however remain dominant over the experimental ones when using four-dimensional standard techniques. Three-dimensional effective theory, on the other hand, is accurate already at one-loop order, therefore providing the most promising route towards robust predictions.
