Baryon Asymmetric Universe from Spontaneous CP Violation
  Spontaneous CP violation, such as the Nelson-Barr (NB) mechanism, is an
attractive scenario for addressing the strong CP problem while realizing the
observed phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix.
However, not only the CKM phase but also the baryon asymmetric Universe
requires sources of CP violation. In this study, we show that a supersymmetric
NB mechanism can naturally accommodate the Affleck-Dine (AD) baryogenesis
within a CP-invariant Lagrangian. The model provides flat directions associated
with new heavy quarks. Focusing on one of the directions, we find that the
correct baryon asymmetry is obtained with a sufficiently low reheating
temperature which does not cause the gravitino problem. Some parameter space is
consistent with the gravitino dark matter. We assess radiative corrections to
the strong CP phase induced by gauge-mediated supersymmetry breaking and
CP-violating heavy fields and show that the strong CP problem is solved in a
viable parameter space where the visible sector supersymmetric particles must
be lighter than O(100) TeV. Even in the case that they are heavier than the TeV
scale, our model predicts the neutron electric dipole moment within the reach
of the near future experiments. Our model addresses the electroweak naturalness
problem, strong CP problem, baryon asymmetric Universe, and dark matter. Then,
the model may give a new compelling paradigm of physics beyond the Standard
Model.
