Emergence of classical structures from the quantum vacuum

Understand

After a quantum phase transition the quantum vacuum can break up to form classical topological defects.

• We examine this process for scalar field models with $Z_2$ symmetry for different quench rates for the phase transition.
• We find that the number density of kinks at late times universally scales as $C m^{1/2} t^{-1/2}$ where $m$ is a mass scale in the model and $C\approx 0.22$; it does not depend on the quench timescale in contrast to the Kibble-Zurek scaling for thermal phase transitions.
• A subleading correction $\propto t^{-3/2}$ to the kink density depends on the details of the phase transition.