2 research outputs found
Can topological defects be formed during preheating ?
We study the dynamics of a scalar field \Phi with the potential
g(|\Phi|^2-\eta^2)^2/2 (g=self-coupling constant, \eta=symmetry breaking scale)
after inflation and make clear whether topological defects can ever be formed
during preheating. In particular, we pay attention to GUT defects (\eta \sim
10^{15}GeV - 10^{17}GeV), and consider three types of fluctuations. The first
one is produced due to parametric resonance, the second is due to the negative
curvature of the potential, and the last is created during inflation. We search
for the parameter region that nonthermal fluctuations of the scalar field
produced through the parametric resonant decay of its homogeneous part do not
lead to defect formation. We find that this region is rather wide, and the GUT
defects are not produced after inflation. This fact shows that the positiveness
of the effective mass square of the field and production of large fluctuations
whose amplitude is as large as that of homogeneous mode are not enough
conditions for full symmetry restoration.Comment: 10 pages, RevTex, 17 postscript figures included. The version to be
published in Physical Review