Phenomenology with trans-Planckian asymptotic safety

The framework of trans-Planckian asymptotic safety has been shown to generate phenomenological predictions in the Standard Model and in some of its new physics extensions. As an example, we use this setup to constrain the parameter space of simple models that can accommodate the measured value of the anomalous magnetic moment of the muon and the relic density of dark matter. In these scenarios, the presence of an interactive UV fixed point in the system of gauge and Yukawa couplings imposes a set of boundary conditions at the Planck scale, which allow one to derive unique phenomenological predictions in each case and distinguish the different representations of the gauge group from one another. In this analysis, a heuristic approach is adopted, which bypasses the functional renormalization group by relying on a parametric description of quantum gravity with universal coefficients that are eventually obtained from low-energy observations. Within this approach a few simplifying approximations are typically introduced, including the computation of matter renormalization group equations at one loop, an arbitrary definition of the position of the Planck scale at 10^19 GeV, and an instantaneous decoupling of gravitational interactions below the Planck scale. We systematically investigate the impact of dropping each of those approximations on the predictions for certain particle physics scenarios and we present numerical and analytical estimates of the uncertainties associated with the predictions from asymptotic safety.