MECHANICS OF COSMIC RINGS

In a flat background, simple non-conducting cosmic string loops have no strictly stationary equilibrium states, but for cosmic string loops of superconducting kind such states will exist, with rotating circular configurations appropriately describable as "cosmic rings" (which may conceivably be a significant contributor to the material content of the universe) whose equilibrium is obtained for zero angular velocity of retrograde characteristics. Such a "cosmic ring" is characterised by just two independent parameters, its mass M and angular momentum J say, corresponding at a microscopic level to two independent quantum number, namely a charge number C and a topological phase number N whose product determines the angular momentum, J = CN, while their ratio determines the local intrinsic state of the string, which may be qualitatively classified as being of "electric" or "magnetic" type depending on whether C N is greater or less than a critical value dependent on the underlying theoretical model. © 1990.