Speaker
Description
Asymptotic grand unification provides an alternative approach to gradually unify gauge couplings in the UV limit, where they reach a non-trivial UV fixed point. Using an economical and realistic particle content setup, we demonstrate that asymptotic grand unification can be achieved in $SO(10)$ with one extra dimension. The top, bottom and tau masses are split, and the smallness of the neutrino mass is explained via seesaw mechanisms. One intermediate scale, the Pati-Salam symmetry breaking scale, is included below the compactification scale. Due to the restricted Higgs content, gauge couplings exhibit asymptotic safety and are thus asymptotically unified, regardless of their initial values. In contrast, Yukawa couplings exhibit asymptotic freedom, requiring explicit unification at the compactification scale if decomposed from the same couplings in $SO(10)$. Asymptotic freedom of the 't Hooft Yukawa couplings is realized when the negative gauge contribution dominates over the positive Yukawa contribution in the competition within the beta functions. The widely-used 126-dimensional Higgs is not recommended in this asymptotic $SO(10)$ GUT with one extra dimension.
