Abstract

Models of brane inflation generate a cosmic superstring network of long, horizon-crossing strings and small, sub-horizon loops. The tension of superstrings differ from that of field theory strings of the GUT variety because modern compactifications lower characteristic energy scales at the bottom of warped throats. A network of these low tension strings exhibits new and interesting cosmological properties. Below a critical string tension, the string loops are long lived and they accumulate and dominate the string network’s total $\Omega$. In addition, the loops’ center of mass motion decays with the universe’s expansion and slow-moving loops will accrete along with the dark matter as perturbations grow and galaxies form. The fortuitous concentration of loops within our own Galaxy facilitates practical experimental searches for superstring loops. Microlensing is a very sensitive means of detection.