Wormhole Dynamics: Nonlinear Collapse and Gravitational-Wave Emission

TL;DR

This paper uses 3D numerical relativity to simulate the nonlinear collapse of an Ellis-Bronnikov wormhole, revealing gravitational-wave emission and a violent rebound after horizon formation.

Contribution

First detailed 3D numerical simulations of unstable wormhole collapse with gravitational-wave signals and shock phenomena.

Findings

Gravitational waves emitted during wormhole collapse are detectable with next-generation detectors.

Collapse leads to horizon formation and a violent phantom bounce causing shock waves.

Detection of such events depends on source distance, asymmetry, and detector sensitivity.

Abstract

We present 3D numerical-relativity evolutions of the unstable Ellis-Bronnikov wormhole using GRTeclyn, starting from exact isotropic initial data for the coupled Einstein-phantom-scalar system. With a flat initial lapse (alpha=1) and full phantom support, truncation-level noise eventually drives the rarefactive instability and rapid throat expansion. To force a clean collapse while breaking spherical symmetry, we reduce the phantom stress-energy support to S_support=0.5 and add a quadrupolar scalar-field perturbation (A_phi=+0.02, sigma_phi=0.5). The resulting compressive evolution forms a trapped surface and emits a gravitational-wave signal whose peak propagates between extraction radii at v approx c, distinct from superluminal CCZ4 constraint modes. After horizon formation the swallowed phantom matter triggers a violent rebound ("phantom bounce") that launches an outward curvature shock. For the moderate perturbation amplitude simulated here, an intermediate-mass (10^3 solar mass) wormhole at D=1 Mpc falls slightly below the Advanced LIGO design sensitivity; detection requires either closer sources, larger initial asymmetries, or next-generation detectors.