Abstract
We explore a new class of natural models which ensure the one-loop divergences in the Higgs mass are cancelled. The top-partners that cancel the top loop are new gauge bosons, and the symmetry relation that ensures the cancellation arises at an infrared fixed point. Such a cancellation mechanism can, a la Little Higgs models, push the scale of new physics that completely solves the hierarchy problem up to 5-10 TeV. When embedded in a supersymmetric model, the stop and gaugino masses provide the cutoffs for the loops, and the mechanism ensures a cancellation between the stop and gaugino mass dependence of the Higgs mass parameter.
Highlights
There have been many attempts to use conformal symmetry to address the hierarchy problem [14,15,16,17,18], but these attempts typically stumble on imperfect cancellations [13, 19], or on the existence of the Planck scale
When embedded in a supersymmetric model, the stop and gaugino masses provide the cutoffs for the loops, and the mechanism ensures a cancellation between the stop and gaugino mass dependence of the Higgs mass parameter
There is a further problem that conformal symmetry cannot help with: what determines the cutoffs in the divergent loops? This can only be answered in a theory where the cutoffs are calculable, so we will examine the case where Little Conformal Symmetry embeded in a supersymmetric model with gauge mediation where the ratio of stop and gaugino masses is fixed by gauge couplings
Summary
The contributions to the quadratic divergence of the Higgs mass come from the following diagrams shown in figure 1. Where λ is the Higgs quartic coupling, yt is the top Yukawa, the i index runs over all the gauge couplings of the Higgs, and C2i(H) is the quadratic Casimir of the Higgs field representation in the ith gauge group [22]. Let us first consider how the top loop could be cancelled by a new non-Abelian gauge boson loop. For this to occur the Higgs would have to be embedded in a multiplet of a new gauge group. (We will return to this point, where the cutoffs will be superpartner masses that will not be equal.) Ensuring the cancellation gives us a requirement that the top Yukawa coupling, yt, is related to the new gauge coupling gN.
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
