Varying Couplings From Orbifold GUTs

Correia, Filipe Paccetti; Schmidt, Michael G.; Tavartkiladze, Zurab

Varying Couplings From Orbifold GUTs

Authors

Correia, Filipe Paccetti

Schmidt, Michael G.

Tavartkiladze, Zurab

Description

We discuss the variation of gauge couplings in time in the framework of orbifold constructions, due to a change of the extra compact dimension's size. Models with gauge coupling unification allow to estimate the variation of the strong coupling constant $\al_3$ and to relate it to a variation of $α_{em}$. The extra-dimensional construction turns out to be crucial for the model to be compatible with data. Within the presented 5D scenarios, the tower of KK states significantly affects gauge coupling running, leads to low scale unification, and provides a suppression of the $\al_3(M_Z)$ variation.
Discussions and references added