Abstract
Effective field theory provides a new perspective on the predictive power of Renormalization Group fixed points. Critical trajectories between different fixed points confine the regions of UV-complete, IR-complete, as well as conformal theories. The associated boundary surfaces cannot be crossed by the Renormalization Group flow of any effective field theory. We delineate cases in which the boundary surface acts as an infrared attractor for generic effective field theories. Gauge-Yukawa theories serve as an example that is both perturbative and of direct phenomenological interest. We identify additional matter fields such that all the observed coupling values of the Standard Model, apart from the Abelian hypercharge, lie within the conformal region. We define a quantitative measure of the predictivity of effective asymptotic safety and demonstrate phenomenological constraints for the associated beyond Standard-Model Yukawa couplings.
Highlights
We look at each simple Standard Model (SM) subgroup by itself which leads to a transparent understanding of why within perturbation theory: (i) additional matter fields can induce fully IR-attractive interacting fixed points for the nonAbelian SM subgroups, while (ii) interacting fixed points with UV-attractive directions are not available, and (iii) Abelian subgroups will always remain trivial
For the SM gauge groups, we have clarified why gauge-Yukawa fixed points with UV-attractive directions cannot occur within the perturbatively controlled regime
We have introduced a novel quantitative measure for the predictivity of general Effective field theory (EFT) and have applied it to gauge-Yukawa BSM extensions
Summary
Effective field theory (EFT) describes all of high-energy physics remarkably well—see [1] for a review of Standard Model (SM) EFT, and [2] for a well-defined EFT of gravity below the Planck scale. Assuming that new physics below the electroweak scale ew is excluded by collider experiments, the EFTs of interest are valid over at most 17 orders of magnitude in energy scales, i.e., 102 GeV ≈ ew NP This motivates us to explore effective asymptotic safety, i.e., the predictivity of RG fixed points over a finite range of scales, cf [65, 70,71,72]. We will demonstrate this observation for the case of gauge-Yukawa theories These make for a suitable example because (i) their fixedpoint structure is both rich enough and perturbatively wellcontrolled [34, 36, 38, 39, 42, 73] and (ii) they are of direct phenomenological significance as possible extensions of the SM [37, 40, 41, 43]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
