Speaker
Description
The hierarchy problem between the electroweak (EW) scale and the Planck scale remains a central puzzle in modern physics. A promising approach is the cosmological selection via volume-weighted dynamics in a multiverse landscape, where the EW scale is dynamically selected as the configuration that maximizes the vacuum energy. This letter proposes a two-step cosmological selection mechanism. By minimally extending the Standard Model with a complex scalar singlet $\phi$ charged under a new $U(1)$ symmetry, the origin of the EW scale is explained elegantly. If the $U(1)$ symmetry is broken explicitly by soft breaking terms, the framework predicts a viable dark matter candidate. Its abundance can be produced via ultra-relativistic freeze-out during reheating and correlates directly with the reheating temperature.
