Oscillating kink behavior in a traversable wormhole

TL;DR

This study numerically explores how the geometry of a traversable wormhole affects the oscillatory behavior and energy transfer of scalar field kinks, revealing the influence of wormhole throat size on defect dynamics.

Contribution

It demonstrates the impact of wormhole throat size on kink oscillations and scalar wave emission, providing new insights into defect dynamics in exotic spacetime geometries.

Findings

Larger wormhole throats enable wider oscillations of kinks across the throat.

Kink crossings emit scalar wave packets, reducing oscillation amplitude.

Wormhole geometry significantly influences defect motion and energy transfer.

Abstract

We investigate the time evolution of spherically symmetric radial domain walls (kinks) in the background of a two-way traversable Simpson-Visser wormhole. By numerically solving the scalar-field equation with a double-well potential, we show that the wormhole throat parameter $a$ has a strong impact on the dynamics of the radial kink: larger $a$ leads to wider throats and allows the domain wall to oscillate across the throat with large amplitude, whereas smaller $a$ confines the motion nearby the throat. In addition, each time the kink crosses the wormhole throat, it emits scalar wave packets, causing its oscillation amplitude to gradually decrease. Our results reveal how the wormhole geometry influences the motion of defects and their energy transfer, providing new insights into the dynamics of topological defects in exotic spacetime.