Rotation slows the instability of Ellis-Bronnikov wormholes

Abstract

We present nonlinear 3+1 evolutions of rotating Ellis-Bronnikov wormholes. We construct stationary rotating drainhole solutions with a spectral solver up to an equatorial rotation velocity of 99% of the speed of light, validate the solver against published symmetric solutions, and correct an inconsistency in a published field equation. Perturbed only by truncation error, the evolutions show that rotation slows the radial instability of the static wormhole. Near 30% of the extremal angular momentum the unperturbed throat expands instead of collapsing, rather than the instability disappearing as second-order perturbation theory suggests. From 58% upward we find no evidence of instability over the evolved times; at the fastest spin this holds at three resolutions. Collapsing rotating throats emit an axisymmetric quadrupolar gravitational-wave burst whose energy grows with spin. Second-order perturbative initial data trigger the instability through their own truncation error, so they are unsuitable for stability studies.