TY - JOUR
T1 - High quality Nelson-Barr solution to the strong CP problem with $\theta=\pi
AU - Perez, Gilad
AU - Shalit, Aviv
PY - 2021/2
Y1 - 2021/2
N2 - We discuss composite UV completions of the Nelson-Barr(NB) solution to the
strong CP problem. In our construction, the CP symmetry is broken spontaneously
by the dynamics of a hidden QCD at $\theta=\pi$. We focus on the minimal
implementation of the NB construction where the visible sector contains one
extra pair of vector-like up/down quarks. We show that the minimal NB theory
suffers from a quality problem, and discuss how composite UV completions may
resolve it. We present a simple calculable scheme, free of a quality problem,
where dynamical CP violation in the hidden sector is mediated through a scalar
portal to the visible sector, which successfully realizes the NB construction.
AB - We discuss composite UV completions of the Nelson-Barr(NB) solution to the
strong CP problem. In our construction, the CP symmetry is broken spontaneously
by the dynamics of a hidden QCD at $\theta=\pi$. We focus on the minimal
implementation of the NB construction where the visible sector contains one
extra pair of vector-like up/down quarks. We show that the minimal NB theory
suffers from a quality problem, and discuss how composite UV completions may
resolve it. We present a simple calculable scheme, free of a quality problem,
where dynamical CP violation in the hidden sector is mediated through a scalar
portal to the visible sector, which successfully realizes the NB construction.
UR - http://www.scopus.com/inward/record.url?scp=85101036776&partnerID=8YFLogxK
U2 - 10.1007/JHEP02(2021)118
DO - 10.1007/JHEP02(2021)118
M3 - Article
SN - 1029-8479
VL - 2021
SP - 1
EP - 27
JO - The journal of high energy physics
JF - The journal of high energy physics
IS - 2
M1 - 118
ER -