Speaker
Prof.
Masahiro Kawasaki
(Institute for Cosmic Ray Research, University of Tokyo)
Description
Axion models have two serious cosmological problems, domain wall and isocurvature perturbation problems.These problems may be solved if the field value of the Peccei-Quinn (PQ) scalar is large during inflation. However, the fluctuations of the PQ field grow after inflation through the parametric resonance and stable axionic strings may be produced, which results in the domain wall problem. We study formation of axionic strings using lattice simulations and obtain the constraints on the PQ breaking scale and the Hubble parameter during inflation.
Primary author
Prof.
Masahiro Kawasaki
(Institute for Cosmic Ray Research, University of Tokyo)
