A Series of Universes Just as the substrate particles of a neutron star are stratum particles in our own universe, so also the substrate particles of our universe are stratum particles in a next-higher-order universe. A series of universes can be extrapolated from the relationship between our universe and a neutron star. Neutron stars play a special role as reference markers in the fractal cosmos. Because neutron stars are degenerate universes, they define the extent of the fractal cosmos. The fractal cosmos terminates at one end with these neutron stars, so universes can be numbered absolutely from the lowest to the highest order. A degenerate universe has a rank less than zero, although it is still an interesting object for mathematical analysis. The highest order of universe is the whole cosmos.