Emergence of classical structures from the quantum vacuum

Mainak Mukhopadhyay; Tanmay Vachaspati; George Zahariade

doi:10.1103/physrevd.102.056021

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arXiv · 2004.07249

Emergence of classical structures from the quantum vacuum

Mainak Mukhopadhyay·Tanmay Vachaspati·George Zahariade

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Abstract

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.

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Mainak Mukhopadhyay, Tanmay Vachaspati, George Zahariade. 2020-09-25. Emergence of classical structures from the quantum vacuum. https://doi.org/10.1103/physrevd.102.056021

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