Mixed neutron-star-plus-wormhole systems: Rotating configurations

TL;DR

This paper introduces models of rapidly rotating neutron stars with central wormholes, constructed within general relativity using ghost scalar fields, and explores their properties and stability.

Contribution

It presents the first rotating neutron-star-plus-wormhole solutions with realistic matter equations of state in general relativity.

Findings

Wormholes have small circumferential radii up to 3 km.

Increasing wormhole size decreases star mass and radius.

The domain of existence retains properties of rotating neutron stars.

Abstract

We present rapidly rotating neutron stars featuring wormholes in their centers. They arise in general relativity in the presence of a ghost scalar field. The nuclear matter is described by a polytropic equation of state, yielding realistic masses and radii for the neutron stars. The wormholes possess small circumferential radii of size up to 3 km. With increasing wormhole size, the masses and radii of the stars decrease, while the domain of existence of these rotating mixed neutron-star-plus-wormhole systems retains the characteristic properties of a rotating neutron star domain. The question of stability of the mixed configurations under consideration is briefly discussed.