Speaker
Description
Without fine-tuning, it is difficult to maintain the utility of the axion as candidate solution to the strong CP problem when it is embedded in UV models due to additional interactions that spoil the IR phenomenology. Anson Hook has presented a model where the axion potential is naturally exponentially suppressed through its interactions with N copies of the same fermionic sector. Although each individual copy contributes a potentially quality-spoiling effective potential, the summation over all N sectors produces cancellations among them which eliminates the lowest-order dependence on the axion and flattens its total potential. The model hinges on a discrete ZN symmetry shifting one copy of the fermions to another cyclically. Here we examine how to embed this system in a UV completion. With a suitable choice of representation, we break SU(NM) into N tensored copies of SU(M) twisted by a semi-direct product with ZN which acts by the desired cyclic permutation.