2000 character limit reached
Automatic Peccei-Quinn symmetry (1812.08174v1)
Published 19 Dec 2018 in hep-ph
Abstract: We present a dynamical (composite) axion model where the Peccei-Quinn (PQ) symmetry arises automatically as a consequence of chirality and gauge symmetry. The Standard Model is simply extended by a confining and chiral $SU(5)$ gauge symmetry. The PQ symmetry coincides with a $B-L$ symmetry of the exotic sector. The theory is protected by construction from quantum gravitational corrections stemming from operators with mass dimension lower than nine.