A High Quality Composite Axion
Ben Lillard
UC Irvine
Axion models are a popular solution to the strong CP problem of the Standard Model: without relying on tuning between unrelated parameters, the axion VEV restores CP as a symmetry of the QCD vacuum, in agreement with measurements of the neutron electric dipole moment. Unfortunately, simple axion models suffer from their own severe fine-tuning: in what is known as the "axion quality problem," the influence of quantum gravity tends to reintroduce the strong CP problem by perturbing the axion VEV. In this talk we present a "high quality" supersymmetric composite axion model, which cures the gravitationally induced fine-tuning problems while also ameliorating the μ problem of the MSSM.