Answer:
During the collapse of a neutron star, its angular momentum is constant. Since there is no net external torque applied to the neutron star, its angular momentum must be conserved.
In order for the star's angular momentum to increase, there would have to be a net external torque exerted on the star and that torque would need to be in the same direction as the star's rotation.
In order for the star's angular momentum to decrease, there would have to be a net external torque exerted on the star and that torque would need to be in the opposite direction of the star's rotation.
