Curvature-induced electroweak symmetry breaking and phase transition of a Higgs-portal dark scalar field

Abstract

This overview of the study arXiv:2407.18845, regarding the possibility of generating gravitational waves from a curvature-induced phase transition of a non-minimally coupled scalar dark matter field with a Higgs-portal, was showcased at the "Workshop on Standard Model and Beyond 2025" of the Corfu Summer Institute 2025. The phase transition dynamics during the transition from inflation to kination were calculated for various inflationary scales, considering both positive and negative values of the non-minimal coupling, while also examining the potential for triggering electroweak symmetry breaking. Notably, kination enhances the GW amplitudes, significantly restricting the viable parameter space. While the GW spectra follow the usual rule for high-frequencies from high inflationary scales, certain regions of the parameter space allow for a potential detection with future experiments.

Figures (6)

• Figure 1: Transition from inflation to kination for a quintessential-like model regarding the Ricci scalar, the Hubble rate, and the EoS parameter for a generic parametrisation $w(t)=\tanh{[\beta_w (t-t_0)]}$ with $\beta_w = 10 H_{\rm inf}$.
• Figure 2: Evolution of the dark scalar potential for $\xi_{\phi}>0$ from inflation (upper left) to kination (lower right). The vertical dash-dotted and dotted lines correspond to the respective barriers and false vacua.
• Figure 3: Evolution of the BSM potential for $\xi_{\phi}<0$ from inflation (upper left) to kination (lower right). The vertical dotted and dash-dotted lines correspond to the respective false vacua and barriers.
• Figure 4: Schematic depiction of gravitational wave emission from bubble collisions after a first-order phase transition of a scalar field. Credit: D. Weir Weir:2019thg.
• Figure 5: Gravitational wave spectra from phase transitions for $\xi_{\phi}>0$ with high scale inflation $H_{\rm inf}=10^{12}$ GeV (top) or low scale inflation $H_{\rm inf}=10^{-8}$ GeV (bottom), and projected detector sensitivities.